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Create Google-style docstrings for my code
def solution(n: int = 1000) -> int: total = 0 num = 0 while 1: num += 3 if num >= n: break total += num num += 2 if num >= n: break total += num num += 1 if num >= n: break total += num num += 3 if num >= n: break total += num num += 1 if num >= n: break total += num num += 2 if num >= n: break total += num num += 3 if num >= n: break total += num return total if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,30 @@+""" +Project Euler Problem 1: https://projecteuler.net/problem=1 + +Multiples of 3 and 5 + +If we list all the natural numbers below 10 that are multiples of 3 or 5, +we get 3, 5, 6 and 9. The sum of these multiples is 23. + +Find the sum of all the multiples of 3 or 5 below 1000. +""" def solution(n: int = 1000) -> int: + """ + This solution is based on the pattern that the successive numbers in the + series follow: 0+3,+2,+1,+3,+1,+2,+3. + Returns the sum of all the multiples of 3 or 5 below n. + + >>> solution(3) + 0 + >>> solution(4) + 3 + >>> solution(10) + 23 + >>> solution(600) + 83700 + """ total = 0 num = 0 @@ -37,4 +61,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_001/sol3.py
Write documentation strings for class attributes
def solution(n: int = 4000000) -> int: i = 1 j = 2 total = 0 while j <= n: if j % 2 == 0: total += j i, j = j, i + j return total if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,37 @@+""" +Project Euler Problem 2: https://projecteuler.net/problem=2 + +Even Fibonacci Numbers + +Each new term in the Fibonacci sequence is generated by adding the previous +two terms. By starting with 1 and 2, the first 10 terms will be: + +1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ... + +By considering the terms in the Fibonacci sequence whose values do not exceed +four million, find the sum of the even-valued terms. + +References: + - https://en.wikipedia.org/wiki/Fibonacci_number +""" def solution(n: int = 4000000) -> int: + """ + Returns the sum of all even fibonacci sequence elements that are lower + or equal to n. + + >>> solution(10) + 10 + >>> solution(15) + 10 + >>> solution(2) + 2 + >>> solution(1) + 0 + >>> solution(34) + 44 + """ i = 1 j = 2 @@ -14,4 +45,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_002/sol1.py
Generate docstrings for exported functions
def solution(n: int = 4000000) -> int: fib = [0, 1] i = 0 while fib[i] <= n: fib.append(fib[i] + fib[i + 1]) if fib[i + 2] > n: break i += 1 total = 0 for j in range(len(fib) - 1): if fib[j] % 2 == 0: total += fib[j] return total if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,37 @@+""" +Project Euler Problem 2: https://projecteuler.net/problem=2 + +Even Fibonacci Numbers + +Each new term in the Fibonacci sequence is generated by adding the previous +two terms. By starting with 1 and 2, the first 10 terms will be: + +1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ... + +By considering the terms in the Fibonacci sequence whose values do not exceed +four million, find the sum of the even-valued terms. + +References: + - https://en.wikipedia.org/wiki/Fibonacci_number +""" def solution(n: int = 4000000) -> int: + """ + Returns the sum of all even fibonacci sequence elements that are lower + or equal to n. + + >>> solution(10) + 10 + >>> solution(15) + 10 + >>> solution(2) + 2 + >>> solution(1) + 0 + >>> solution(34) + 44 + """ fib = [0, 1] i = 0 @@ -18,4 +49,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_002/sol5.py
Add docstrings to clarify complex logic
def solution(n: int = 600851475143) -> int: try: n = int(n) except (TypeError, ValueError): raise TypeError("Parameter n must be int or castable to int.") if n <= 0: raise ValueError("Parameter n must be greater than or equal to one.") i = 2 ans = 0 if n == 2: return 2 while n > 2: while n % i != 0: i += 1 ans = i while n % i == 0: n = n // i i += 1 return int(ans) if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,46 @@+""" +Project Euler Problem 3: https://projecteuler.net/problem=3 + +Largest prime factor + +The prime factors of 13195 are 5, 7, 13 and 29. + +What is the largest prime factor of the number 600851475143? + +References: + - https://en.wikipedia.org/wiki/Prime_number#Unique_factorization +""" def solution(n: int = 600851475143) -> int: + """ + Returns the largest prime factor of a given number n. + + >>> solution(13195) + 29 + >>> solution(10) + 5 + >>> solution(17) + 17 + >>> solution(3.4) + 3 + >>> solution(0) + Traceback (most recent call last): + ... + ValueError: Parameter n must be greater than or equal to one. + >>> solution(-17) + Traceback (most recent call last): + ... + ValueError: Parameter n must be greater than or equal to one. + >>> solution([]) + Traceback (most recent call last): + ... + TypeError: Parameter n must be int or castable to int. + >>> solution("asd") + Traceback (most recent call last): + ... + TypeError: Parameter n must be int or castable to int. + """ try: n = int(n) @@ -23,4 +63,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_003/sol3.py
Turn comments into proper docstrings
def solution(n: int = 998001) -> int: # fetches the next number for number in range(n - 1, 9999, -1): str_number = str(number) # checks whether 'str_number' is a palindrome. if str_number == str_number[::-1]: divisor = 999 # if 'number' is a product of two 3-digit numbers # then number is the answer otherwise fetch next number. while divisor != 99: if (number % divisor == 0) and (len(str(number // divisor)) == 3.0): return number divisor -= 1 raise ValueError("That number is larger than our acceptable range.") if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,34 @@+""" +Project Euler Problem 4: https://projecteuler.net/problem=4 + +Largest palindrome product + +A palindromic number reads the same both ways. The largest palindrome made +from the product of two 2-digit numbers is 9009 = 91 x 99. + +Find the largest palindrome made from the product of two 3-digit numbers. + +References: + - https://en.wikipedia.org/wiki/Palindromic_number +""" def solution(n: int = 998001) -> int: + """ + Returns the largest palindrome made from the product of two 3-digit + numbers which is less than n. + + >>> solution(20000) + 19591 + >>> solution(30000) + 29992 + >>> solution(40000) + 39893 + >>> solution(10000) + Traceback (most recent call last): + ... + ValueError: That number is larger than our acceptable range. + """ # fetches the next number for number in range(n - 1, 9999, -1): @@ -20,4 +48,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_004/sol1.py
Generate consistent docstrings
import math def is_prime(number: int) -> bool: if 1 < number < 4: # 2 and 3 are primes return True elif number < 2 or number % 2 == 0 or number % 3 == 0: # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes return False # All primes number are in format of 6k +/- 1 for i in range(5, int(math.sqrt(number) + 1), 6): if number % i == 0 or number % (i + 2) == 0: return False return True def solution(n: int = 600851475143) -> int: try: n = int(n) except (TypeError, ValueError): raise TypeError("Parameter n must be int or castable to int.") if n <= 0: raise ValueError("Parameter n must be greater than or equal to one.") max_number = 0 if is_prime(n): return n while n % 2 == 0: n //= 2 if is_prime(n): return n for i in range(3, int(math.sqrt(n)) + 1, 2): if n % i == 0: if is_prime(n // i): max_number = n // i break elif is_prime(i): max_number = i return max_number if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,8 +1,38 @@+""" +Project Euler Problem 3: https://projecteuler.net/problem=3 + +Largest prime factor + +The prime factors of 13195 are 5, 7, 13 and 29. + +What is the largest prime factor of the number 600851475143? + +References: + - https://en.wikipedia.org/wiki/Prime_number#Unique_factorization +""" import math def is_prime(number: int) -> bool: + """Checks to see if a number is a prime in O(sqrt(n)). + A number is prime if it has exactly two factors: 1 and itself. + Returns boolean representing primality of given number (i.e., if the + result is true, then the number is indeed prime else it is not). + + >>> is_prime(2) + True + >>> is_prime(3) + True + >>> is_prime(27) + False + >>> is_prime(2999) + True + >>> is_prime(0) + False + >>> is_prime(1) + False + """ if 1 < number < 4: # 2 and 3 are primes @@ -19,6 +49,34 @@ def solution(n: int = 600851475143) -> int: + """ + Returns the largest prime factor of a given number n. + + >>> solution(13195) + 29 + >>> solution(10) + 5 + >>> solution(17) + 17 + >>> solution(3.4) + 3 + >>> solution(0) + Traceback (most recent call last): + ... + ValueError: Parameter n must be greater than or equal to one. + >>> solution(-17) + Traceback (most recent call last): + ... + ValueError: Parameter n must be greater than or equal to one. + >>> solution([]) + Traceback (most recent call last): + ... + TypeError: Parameter n must be int or castable to int. + >>> solution("asd") + Traceback (most recent call last): + ... + TypeError: Parameter n must be int or castable to int. + """ try: n = int(n) @@ -44,4 +102,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_003/sol1.py
Document this code for team use
def solution(n: int = 600851475143) -> int: try: n = int(n) except (TypeError, ValueError): raise TypeError("Parameter n must be int or castable to int.") if n <= 0: raise ValueError("Parameter n must be greater than or equal to one.") prime = 1 i = 2 while i * i <= n: while n % i == 0: prime = i n //= i i += 1 if n > 1: prime = n return int(prime) if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,46 @@+""" +Project Euler Problem 3: https://projecteuler.net/problem=3 + +Largest prime factor + +The prime factors of 13195 are 5, 7, 13 and 29. + +What is the largest prime factor of the number 600851475143? + +References: + - https://en.wikipedia.org/wiki/Prime_number#Unique_factorization +""" def solution(n: int = 600851475143) -> int: + """ + Returns the largest prime factor of a given number n. + + >>> solution(13195) + 29 + >>> solution(10) + 5 + >>> solution(17) + 17 + >>> solution(3.4) + 3 + >>> solution(0) + Traceback (most recent call last): + ... + ValueError: Parameter n must be greater than or equal to one. + >>> solution(-17) + Traceback (most recent call last): + ... + ValueError: Parameter n must be greater than or equal to one. + >>> solution([]) + Traceback (most recent call last): + ... + TypeError: Parameter n must be int or castable to int. + >>> solution("asd") + Traceback (most recent call last): + ... + TypeError: Parameter n must be int or castable to int. + """ try: n = int(n) @@ -21,4 +61,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_003/sol2.py
Add docstrings for internal functions
from maths.greatest_common_divisor import greatest_common_divisor """ Project Euler Problem 5: https://projecteuler.net/problem=5 Smallest multiple 2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder. What is the smallest positive number that is _evenly divisible_ by all of the numbers from 1 to 20? References: - https://en.wiktionary.org/wiki/evenly_divisible - https://en.wikipedia.org/wiki/Euclidean_algorithm - https://en.wikipedia.org/wiki/Least_common_multiple """ def lcm(x: int, y: int) -> int: return (x * y) // greatest_common_divisor(x, y) def solution(n: int = 20) -> int: g = 1 for i in range(1, n + 1): g = lcm(g, i) return g if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -19,11 +19,36 @@ def lcm(x: int, y: int) -> int: + """ + Least Common Multiple. + + Using the property that lcm(a, b) * greatest_common_divisor(a, b) = a*b + + >>> lcm(3, 15) + 15 + >>> lcm(1, 27) + 27 + >>> lcm(13, 27) + 351 + >>> lcm(64, 48) + 192 + """ return (x * y) // greatest_common_divisor(x, y) def solution(n: int = 20) -> int: + """ + Returns the smallest positive number that is evenly divisible (divisible + with no remainder) by all of the numbers from 1 to n. + + >>> solution(10) + 2520 + >>> solution(15) + 360360 + >>> solution(22) + 232792560 + """ g = 1 for i in range(1, n + 1): @@ -32,4 +57,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_005/sol2.py
Write reusable docstrings
import math from decimal import Decimal, getcontext def solution(n: int = 4000000) -> int: try: n = int(n) except (TypeError, ValueError): raise TypeError("Parameter n must be int or castable to int.") if n <= 0: raise ValueError("Parameter n must be greater than or equal to one.") getcontext().prec = 100 phi = (Decimal(5) ** Decimal("0.5") + 1) / Decimal(2) index = (math.floor(math.log(n * (phi + 2), phi) - 1) // 3) * 3 + 2 num = Decimal(round(phi ** Decimal(index + 1))) / (phi + 2) total = num // 2 return int(total) if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,9 +1,58 @@+""" +Project Euler Problem 2: https://projecteuler.net/problem=2 + +Even Fibonacci Numbers + +Each new term in the Fibonacci sequence is generated by adding the previous +two terms. By starting with 1 and 2, the first 10 terms will be: + +1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ... + +By considering the terms in the Fibonacci sequence whose values do not exceed +four million, find the sum of the even-valued terms. + +References: + - https://en.wikipedia.org/wiki/Fibonacci_number +""" import math from decimal import Decimal, getcontext def solution(n: int = 4000000) -> int: + """ + Returns the sum of all even fibonacci sequence elements that are lower + or equal to n. + + >>> solution(10) + 10 + >>> solution(15) + 10 + >>> solution(2) + 2 + >>> solution(1) + 0 + >>> solution(34) + 44 + >>> solution(3.4) + 2 + >>> solution(0) + Traceback (most recent call last): + ... + ValueError: Parameter n must be greater than or equal to one. + >>> solution(-17) + Traceback (most recent call last): + ... + ValueError: Parameter n must be greater than or equal to one. + >>> solution([]) + Traceback (most recent call last): + ... + TypeError: Parameter n must be int or castable to int. + >>> solution("asd") + Traceback (most recent call last): + ... + TypeError: Parameter n must be int or castable to int. + """ try: n = int(n) @@ -21,4 +70,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_002/sol4.py
Add docstrings to clarify complex logic
def solution(n: int = 20) -> int: try: n = int(n) except (TypeError, ValueError): raise TypeError("Parameter n must be int or castable to int.") if n <= 0: raise ValueError("Parameter n must be greater than or equal to one.") i = 0 while 1: i += n * (n - 1) nfound = 0 for j in range(2, n): if i % j != 0: nfound = 1 break if nfound == 0: if i == 0: i = 1 return i return None if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,49 @@+""" +Project Euler Problem 5: https://projecteuler.net/problem=5 + +Smallest multiple + +2520 is the smallest number that can be divided by each of the numbers +from 1 to 10 without any remainder. + +What is the smallest positive number that is _evenly divisible_ by all +of the numbers from 1 to 20? + +References: + - https://en.wiktionary.org/wiki/evenly_divisible +""" def solution(n: int = 20) -> int: + """ + Returns the smallest positive number that is evenly divisible (divisible + with no remainder) by all of the numbers from 1 to n. + + >>> solution(10) + 2520 + >>> solution(15) + 360360 + >>> solution(22) + 232792560 + >>> solution(3.4) + 6 + >>> solution(0) + Traceback (most recent call last): + ... + ValueError: Parameter n must be greater than or equal to one. + >>> solution(-17) + Traceback (most recent call last): + ... + ValueError: Parameter n must be greater than or equal to one. + >>> solution([]) + Traceback (most recent call last): + ... + TypeError: Parameter n must be int or castable to int. + >>> solution("asd") + Traceback (most recent call last): + ... + TypeError: Parameter n must be int or castable to int. + """ try: n = int(n) @@ -24,4 +67,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_005/sol1.py
Document classes and their methods
def solution(n: int = 4000000) -> int: even_fibs = [] a, b = 0, 1 while b <= n: if b % 2 == 0: even_fibs.append(b) a, b = b, a + b return sum(even_fibs) if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,37 @@+""" +Project Euler Problem 2: https://projecteuler.net/problem=2 + +Even Fibonacci Numbers + +Each new term in the Fibonacci sequence is generated by adding the previous +two terms. By starting with 1 and 2, the first 10 terms will be: + +1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ... + +By considering the terms in the Fibonacci sequence whose values do not exceed +four million, find the sum of the even-valued terms. + +References: + - https://en.wikipedia.org/wiki/Fibonacci_number +""" def solution(n: int = 4000000) -> int: + """ + Returns the sum of all even fibonacci sequence elements that are lower + or equal to n. + + >>> solution(10) + 10 + >>> solution(15) + 10 + >>> solution(2) + 2 + >>> solution(1) + 0 + >>> solution(34) + 44 + """ even_fibs = [] a, b = 0, 1 @@ -12,4 +43,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_002/sol2.py
Add well-formatted docstrings
def solution(n: int = 100) -> int: sum_of_squares = 0 sum_of_ints = 0 for i in range(1, n + 1): sum_of_squares += i**2 sum_of_ints += i return sum_of_ints**2 - sum_of_squares if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,36 @@+""" +Project Euler Problem 6: https://projecteuler.net/problem=6 + +Sum square difference + +The sum of the squares of the first ten natural numbers is, + 1^2 + 2^2 + ... + 10^2 = 385 + +The square of the sum of the first ten natural numbers is, + (1 + 2 + ... + 10)^2 = 55^2 = 3025 + +Hence the difference between the sum of the squares of the first ten +natural numbers and the square of the sum is 3025 - 385 = 2640. + +Find the difference between the sum of the squares of the first one +hundred natural numbers and the square of the sum. +""" def solution(n: int = 100) -> int: + """ + Returns the difference between the sum of the squares of the first n + natural numbers and the square of the sum. + + >>> solution(10) + 2640 + >>> solution(15) + 13160 + >>> solution(20) + 41230 + >>> solution(50) + 1582700 + """ sum_of_squares = 0 sum_of_ints = 0 @@ -11,4 +41,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_006/sol1.py
Create docstrings for each class method
from math import exp def f(x: float) -> float: return 8 * x - 2 * exp(-x) def secant_method(lower_bound: float, upper_bound: float, repeats: int) -> float: x0 = lower_bound x1 = upper_bound for _ in range(repeats): x0, x1 = x1, x1 - (f(x1) * (x1 - x0)) / (f(x1) - f(x0)) return x1 if __name__ == "__main__": print(f"Example: {secant_method(1, 3, 2)}")
--- +++ @@ -1,12 +1,24 @@+""" +Implementing Secant method in Python +Author: dimgrichr +""" from math import exp def f(x: float) -> float: + """ + >>> f(5) + 39.98652410600183 + """ return 8 * x - 2 * exp(-x) def secant_method(lower_bound: float, upper_bound: float, repeats: int) -> float: + """ + >>> secant_method(1, 3, 2) + 0.2139409276214589 + """ x0 = lower_bound x1 = upper_bound for _ in range(repeats): @@ -15,4 +27,4 @@ if __name__ == "__main__": - print(f"Example: {secant_method(1, 3, 2)}")+ print(f"Example: {secant_method(1, 3, 2)}")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/maths/numerical_analysis/secant_method.py
Create docstrings for each class method
from math import sqrt def is_prime(number: int) -> bool: if 1 < number < 4: # 2 and 3 are primes return True elif number < 2 or number % 2 == 0 or number % 3 == 0: # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes return False # All primes number are in format of 6k +/- 1 for i in range(5, int(sqrt(number) + 1), 6): if number % i == 0 or number % (i + 2) == 0: return False return True def solution(nth: int = 10001) -> int: count = 0 number = 1 while count != nth and number < 3: number += 1 if is_prime(number): count += 1 while count != nth: number += 2 if is_prime(number): count += 1 return number if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,8 +1,39 @@+""" +Project Euler Problem 7: https://projecteuler.net/problem=7 + +10001st prime + +By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we +can see that the 6th prime is 13. + +What is the 10001st prime number? + +References: + - https://en.wikipedia.org/wiki/Prime_number +""" from math import sqrt def is_prime(number: int) -> bool: + """Checks to see if a number is a prime in O(sqrt(n)). + A number is prime if it has exactly two factors: 1 and itself. + Returns boolean representing primality of given number (i.e., if the + result is true, then the number is indeed prime else it is not). + + >>> is_prime(2) + True + >>> is_prime(3) + True + >>> is_prime(27) + False + >>> is_prime(2999) + True + >>> is_prime(0) + False + >>> is_prime(1) + False + """ if 1 < number < 4: # 2 and 3 are primes @@ -19,6 +50,22 @@ def solution(nth: int = 10001) -> int: + """ + Returns the n-th prime number. + + >>> solution(6) + 13 + >>> solution(1) + 2 + >>> solution(3) + 5 + >>> solution(20) + 71 + >>> solution(50) + 229 + >>> solution(100) + 541 + """ count = 0 number = 1 @@ -34,4 +81,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_007/sol1.py
Generate docstrings for script automation
import math def solution(n: int = 100) -> int: sum_of_squares = sum(i * i for i in range(1, n + 1)) square_of_sum = int(math.pow(sum(range(1, n + 1)), 2)) return square_of_sum - sum_of_squares if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,8 +1,38 @@+""" +Project Euler Problem 6: https://projecteuler.net/problem=6 + +Sum square difference + +The sum of the squares of the first ten natural numbers is, + 1^2 + 2^2 + ... + 10^2 = 385 + +The square of the sum of the first ten natural numbers is, + (1 + 2 + ... + 10)^2 = 55^2 = 3025 + +Hence the difference between the sum of the squares of the first ten +natural numbers and the square of the sum is 3025 - 385 = 2640. + +Find the difference between the sum of the squares of the first one +hundred natural numbers and the square of the sum. +""" import math def solution(n: int = 100) -> int: + """ + Returns the difference between the sum of the squares of the first n + natural numbers and the square of the sum. + + >>> solution(10) + 2640 + >>> solution(15) + 13160 + >>> solution(20) + 41230 + >>> solution(50) + 1582700 + """ sum_of_squares = sum(i * i for i in range(1, n + 1)) square_of_sum = int(math.pow(sum(range(1, n + 1)), 2)) @@ -10,4 +40,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_006/sol3.py
Replace inline comments with docstrings
def solution(n: int = 100) -> int: sum_cubes = (n * (n + 1) // 2) ** 2 sum_squares = n * (n + 1) * (2 * n + 1) // 6 return sum_cubes - sum_squares if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,36 @@+""" +Project Euler Problem 6: https://projecteuler.net/problem=6 + +Sum square difference + +The sum of the squares of the first ten natural numbers is, + 1^2 + 2^2 + ... + 10^2 = 385 + +The square of the sum of the first ten natural numbers is, + (1 + 2 + ... + 10)^2 = 55^2 = 3025 + +Hence the difference between the sum of the squares of the first ten +natural numbers and the square of the sum is 3025 - 385 = 2640. + +Find the difference between the sum of the squares of the first one +hundred natural numbers and the square of the sum. +""" def solution(n: int = 100) -> int: + """ + Returns the difference between the sum of the squares of the first n + natural numbers and the square of the sum. + + >>> solution(10) + 2640 + >>> solution(15) + 13160 + >>> solution(20) + 41230 + >>> solution(50) + 1582700 + """ sum_cubes = (n * (n + 1) // 2) ** 2 sum_squares = n * (n + 1) * (2 * n + 1) // 6 @@ -8,4 +38,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_006/sol2.py
Write docstrings for data processing functions
def solution(n: int = 998001) -> int: answer = 0 for i in range(999, 99, -1): # 3 digit numbers range from 999 down to 100 for j in range(999, 99, -1): product_string = str(i * j) if product_string == product_string[::-1] and i * j < n: answer = max(answer, i * j) return answer if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,30 @@+""" +Project Euler Problem 4: https://projecteuler.net/problem=4 + +Largest palindrome product + +A palindromic number reads the same both ways. The largest palindrome made +from the product of two 2-digit numbers is 9009 = 91 x 99. + +Find the largest palindrome made from the product of two 3-digit numbers. + +References: + - https://en.wikipedia.org/wiki/Palindromic_number +""" def solution(n: int = 998001) -> int: + """ + Returns the largest palindrome made from the product of two 3-digit + numbers which is less than n. + + >>> solution(20000) + 19591 + >>> solution(30000) + 29992 + >>> solution(40000) + 39893 + """ answer = 0 for i in range(999, 99, -1): # 3 digit numbers range from 999 down to 100 @@ -12,4 +36,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_004/sol2.py
Add docstrings to meet PEP guidelines
def perfect(number: int) -> bool: if not isinstance(number, int): raise ValueError("number must be an integer") if number <= 0: return False return sum(i for i in range(1, number // 2 + 1) if number % i == 0) == number if __name__ == "__main__": from doctest import testmod testmod() print("Program to check whether a number is a Perfect number or not...") try: number = int(input("Enter a positive integer: ").strip()) except ValueError: msg = "number must be an integer" raise ValueError(msg) print(f"{number} is {'' if perfect(number) else 'not '}a Perfect Number.")
--- +++ @@ -1,6 +1,70 @@+""" +== Perfect Number == +In number theory, a perfect number is a positive integer that is equal to the sum of +its positive divisors, excluding the number itself. +For example: 6 ==> divisors[1, 2, 3, 6] + Excluding 6, the sum(divisors) is 1 + 2 + 3 = 6 + So, 6 is a Perfect Number + +Other examples of Perfect Numbers: 28, 486, ... + +https://en.wikipedia.org/wiki/Perfect_number +""" def perfect(number: int) -> bool: + """ + Check if a number is a perfect number. + + A perfect number is a positive integer that is equal to the sum of its proper + divisors (excluding itself). + + Args: + number: The number to be checked. + + Returns: + True if the number is a perfect number otherwise, False. + Start from 1 because dividing by 0 will raise ZeroDivisionError. + A number at most can be divisible by the half of the number except the number + itself. For example, 6 is at most can be divisible by 3 except by 6 itself. + Examples: + >>> perfect(27) + False + >>> perfect(28) + True + >>> perfect(29) + False + >>> perfect(6) + True + >>> perfect(12) + False + >>> perfect(496) + True + >>> perfect(8128) + True + >>> perfect(0) + False + >>> perfect(-1) + False + >>> perfect(33550336) # Large perfect number + True + >>> perfect(33550337) # Just above a large perfect number + False + >>> perfect(1) # Edge case: 1 is not a perfect number + False + >>> perfect("123") # String representation of a number + Traceback (most recent call last): + ... + ValueError: number must be an integer + >>> perfect(12.34) + Traceback (most recent call last): + ... + ValueError: number must be an integer + >>> perfect("Hello") + Traceback (most recent call last): + ... + ValueError: number must be an integer + """ if not isinstance(number, int): raise ValueError("number must be an integer") if number <= 0: @@ -19,4 +83,4 @@ msg = "number must be an integer" raise ValueError(msg) - print(f"{number} is {'' if perfect(number) else 'not '}a Perfect Number.")+ print(f"{number} is {'' if perfect(number) else 'not '}a Perfect Number.")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/maths/perfect_number.py
Please document this code using docstrings
import itertools import math def is_prime(number: int) -> bool: if 1 < number < 4: # 2 and 3 are primes return True elif number < 2 or number % 2 == 0 or number % 3 == 0: # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes return False # All primes number are in format of 6k +/- 1 for i in range(5, int(math.sqrt(number) + 1), 6): if number % i == 0 or number % (i + 2) == 0: return False return True def prime_generator(): num = 2 while True: if is_prime(num): yield num num += 1 def solution(nth: int = 10001) -> int: return next(itertools.islice(prime_generator(), nth - 1, nth)) if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,9 +1,40 @@+""" +Project Euler Problem 7: https://projecteuler.net/problem=7 + +10001st prime + +By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we +can see that the 6th prime is 13. + +What is the 10001st prime number? + +References: + - https://en.wikipedia.org/wiki/Prime_number +""" import itertools import math def is_prime(number: int) -> bool: + """Checks to see if a number is a prime in O(sqrt(n)). + A number is prime if it has exactly two factors: 1 and itself. + Returns boolean representing primality of given number (i.e., if the + result is true, then the number is indeed prime else it is not). + + >>> is_prime(2) + True + >>> is_prime(3) + True + >>> is_prime(27) + False + >>> is_prime(2999) + True + >>> is_prime(0) + False + >>> is_prime(1) + False + """ if 1 < number < 4: # 2 and 3 are primes @@ -20,6 +51,9 @@ def prime_generator(): + """ + Generate a sequence of prime numbers + """ num = 2 while True: @@ -29,8 +63,24 @@ def solution(nth: int = 10001) -> int: + """ + Returns the n-th prime number. + + >>> solution(6) + 13 + >>> solution(1) + 2 + >>> solution(3) + 5 + >>> solution(20) + 71 + >>> solution(50) + 229 + >>> solution(100) + 541 + """ return next(itertools.islice(prime_generator(), nth - 1, nth)) if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_007/sol3.py
Add docstrings to existing functions
def power(base: int, exponent: int) -> float: return base * power(base, (exponent - 1)) if exponent else 1 if __name__ == "__main__": from doctest import testmod testmod() print("Raise base to the power of exponent using recursion...") base = int(input("Enter the base: ").strip()) exponent = int(input("Enter the exponent: ").strip()) result = power(base, abs(exponent)) if exponent < 0: # power() does not properly deal w/ negative exponents result = 1 / result print(f"{base} to the power of {exponent} is {result}")
--- +++ @@ -1,6 +1,52 @@+""" +== Raise base to the power of exponent using recursion == + Input --> + Enter the base: 3 + Enter the exponent: 4 + Output --> + 3 to the power of 4 is 81 + Input --> + Enter the base: 2 + Enter the exponent: 0 + Output --> + 2 to the power of 0 is 1 +""" def power(base: int, exponent: int) -> float: + """ + Calculate the power of a base raised to an exponent. + + >>> power(3, 4) + 81 + >>> power(2, 0) + 1 + >>> all(power(base, exponent) == pow(base, exponent) + ... for base in range(-10, 10) for exponent in range(10)) + True + >>> power('a', 1) + 'a' + >>> power('a', 2) + Traceback (most recent call last): + ... + TypeError: can't multiply sequence by non-int of type 'str' + >>> power('a', 'b') + Traceback (most recent call last): + ... + TypeError: unsupported operand type(s) for -: 'str' and 'int' + >>> power(2, -1) + Traceback (most recent call last): + ... + RecursionError: maximum recursion depth exceeded + >>> power(0, 0) + 1 + >>> power(0, 1) + 0 + >>> power(5,6) + 15625 + >>> power(23, 12) + 21914624432020321 + """ return base * power(base, (exponent - 1)) if exponent else 1 @@ -14,4 +60,4 @@ result = power(base, abs(exponent)) if exponent < 0: # power() does not properly deal w/ negative exponents result = 1 / result - print(f"{base} to the power of {exponent} is {result}")+ print(f"{base} to the power of {exponent} is {result}")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/maths/power_using_recursion.py
Add docstrings following best practices
import sys N = ( "73167176531330624919225119674426574742355349194934" "96983520312774506326239578318016984801869478851843" "85861560789112949495459501737958331952853208805511" "12540698747158523863050715693290963295227443043557" "66896648950445244523161731856403098711121722383113" "62229893423380308135336276614282806444486645238749" "30358907296290491560440772390713810515859307960866" "70172427121883998797908792274921901699720888093776" "65727333001053367881220235421809751254540594752243" "52584907711670556013604839586446706324415722155397" "53697817977846174064955149290862569321978468622482" "83972241375657056057490261407972968652414535100474" "82166370484403199890008895243450658541227588666881" "16427171479924442928230863465674813919123162824586" "17866458359124566529476545682848912883142607690042" "24219022671055626321111109370544217506941658960408" "07198403850962455444362981230987879927244284909188" "84580156166097919133875499200524063689912560717606" "05886116467109405077541002256983155200055935729725" "71636269561882670428252483600823257530420752963450" ) def str_eval(s: str) -> int: product = 1 for digit in s: product *= int(digit) return product def solution(n: str = N) -> int: largest_product = -sys.maxsize - 1 substr = n[:13] cur_index = 13 while cur_index < len(n) - 13: if int(n[cur_index]) >= int(substr[0]): substr = substr[1:] + n[cur_index] cur_index += 1 else: largest_product = max(largest_product, str_eval(substr)) substr = n[cur_index : cur_index + 13] cur_index += 13 return largest_product if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,3 +1,35 @@+""" +Project Euler Problem 8: https://projecteuler.net/problem=8 + +Largest product in a series + +The four adjacent digits in the 1000-digit number that have the greatest +product are 9 x 9 x 8 x 9 = 5832. + + 73167176531330624919225119674426574742355349194934 + 96983520312774506326239578318016984801869478851843 + 85861560789112949495459501737958331952853208805511 + 12540698747158523863050715693290963295227443043557 + 66896648950445244523161731856403098711121722383113 + 62229893423380308135336276614282806444486645238749 + 30358907296290491560440772390713810515859307960866 + 70172427121883998797908792274921901699720888093776 + 65727333001053367881220235421809751254540594752243 + 52584907711670556013604839586446706324415722155397 + 53697817977846174064955149290862569321978468622482 + 83972241375657056057490261407972968652414535100474 + 82166370484403199890008895243450658541227588666881 + 16427171479924442928230863465674813919123162824586 + 17866458359124566529476545682848912883142607690042 + 24219022671055626321111109370544217506941658960408 + 07198403850962455444362981230987879927244284909188 + 84580156166097919133875499200524063689912560717606 + 05886116467109405077541002256983155200055935729725 + 71636269561882670428252483600823257530420752963450 + +Find the thirteen adjacent digits in the 1000-digit number that have the +greatest product. What is the value of this product? +""" import sys @@ -26,6 +58,14 @@ def str_eval(s: str) -> int: + """ + Returns product of digits in given string n + + >>> str_eval("987654321") + 362880 + >>> str_eval("22222222") + 256 + """ product = 1 for digit in s: @@ -34,6 +74,10 @@ def solution(n: str = N) -> int: + """ + Find the thirteen adjacent digits in the 1000-digit number n that have + the greatest product and returns it. + """ largest_product = -sys.maxsize - 1 substr = n[:13] @@ -50,4 +94,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_008/sol3.py
Create docstrings for each class method
import math def is_prime(number: int) -> bool: if 1 < number < 4: # 2 and 3 are primes return True elif number < 2 or number % 2 == 0 or number % 3 == 0: # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes return False # All primes number are in format of 6k +/- 1 for i in range(5, int(math.sqrt(number) + 1), 6): if number % i == 0 or number % (i + 2) == 0: return False return True def solution(nth: int = 10001) -> int: try: nth = int(nth) except (TypeError, ValueError): raise TypeError("Parameter nth must be int or castable to int.") from None if nth <= 0: raise ValueError("Parameter nth must be greater than or equal to one.") primes: list[int] = [] num = 2 while len(primes) < nth: if is_prime(num): primes.append(num) num += 1 else: num += 1 return primes[len(primes) - 1] if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,8 +1,39 @@+""" +Project Euler Problem 7: https://projecteuler.net/problem=7 + +10001st prime + +By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we +can see that the 6th prime is 13. + +What is the 10001st prime number? + +References: + - https://en.wikipedia.org/wiki/Prime_number +""" import math def is_prime(number: int) -> bool: + """Checks to see if a number is a prime in O(sqrt(n)). + A number is prime if it has exactly two factors: 1 and itself. + Returns boolean representing primality of given number (i.e., if the + result is true, then the number is indeed prime else it is not). + + >>> is_prime(2) + True + >>> is_prime(3) + True + >>> is_prime(27) + False + >>> is_prime(2999) + True + >>> is_prime(0) + False + >>> is_prime(1) + False + """ if 1 < number < 4: # 2 and 3 are primes @@ -19,6 +50,40 @@ def solution(nth: int = 10001) -> int: + """ + Returns the n-th prime number. + + >>> solution(6) + 13 + >>> solution(1) + 2 + >>> solution(3) + 5 + >>> solution(20) + 71 + >>> solution(50) + 229 + >>> solution(100) + 541 + >>> solution(3.4) + 5 + >>> solution(0) + Traceback (most recent call last): + ... + ValueError: Parameter nth must be greater than or equal to one. + >>> solution(-17) + Traceback (most recent call last): + ... + ValueError: Parameter nth must be greater than or equal to one. + >>> solution([]) + Traceback (most recent call last): + ... + TypeError: Parameter nth must be int or castable to int. + >>> solution("asd") + Traceback (most recent call last): + ... + TypeError: Parameter nth must be int or castable to int. + """ try: nth = int(nth) @@ -38,4 +103,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_007/sol2.py
Write Python docstrings for this snippet
def multiplicative_persistence(num: int) -> int: if not isinstance(num, int): raise ValueError("multiplicative_persistence() only accepts integral values") if num < 0: raise ValueError("multiplicative_persistence() does not accept negative values") steps = 0 num_string = str(num) while len(num_string) != 1: numbers = [int(i) for i in num_string] total = 1 for i in range(len(numbers)): total *= numbers[i] num_string = str(total) steps += 1 return steps def additive_persistence(num: int) -> int: if not isinstance(num, int): raise ValueError("additive_persistence() only accepts integral values") if num < 0: raise ValueError("additive_persistence() does not accept negative values") steps = 0 num_string = str(num) while len(num_string) != 1: numbers = [int(i) for i in num_string] total = 0 for i in range(len(numbers)): total += numbers[i] num_string = str(total) steps += 1 return steps if __name__ == "__main__": import doctest doctest.testmod()
--- +++ @@ -1,4 +1,20 @@ def multiplicative_persistence(num: int) -> int: + """ + Return the persistence of a given number. + + https://en.wikipedia.org/wiki/Persistence_of_a_number + + >>> multiplicative_persistence(217) + 2 + >>> multiplicative_persistence(-1) + Traceback (most recent call last): + ... + ValueError: multiplicative_persistence() does not accept negative values + >>> multiplicative_persistence("long number") + Traceback (most recent call last): + ... + ValueError: multiplicative_persistence() only accepts integral values + """ if not isinstance(num, int): raise ValueError("multiplicative_persistence() only accepts integral values") @@ -22,6 +38,22 @@ def additive_persistence(num: int) -> int: + """ + Return the persistence of a given number. + + https://en.wikipedia.org/wiki/Persistence_of_a_number + + >>> additive_persistence(199) + 3 + >>> additive_persistence(-1) + Traceback (most recent call last): + ... + ValueError: additive_persistence() does not accept negative values + >>> additive_persistence("long number") + Traceback (most recent call last): + ... + ValueError: additive_persistence() only accepts integral values + """ if not isinstance(num, int): raise ValueError("additive_persistence() only accepts integral values") @@ -47,4 +79,4 @@ if __name__ == "__main__": import doctest - doctest.testmod()+ doctest.testmod()
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/maths/persistence.py
Fully document this Python code with docstrings
from __future__ import annotations from collections.abc import MutableSequence class Polynomial: def __init__(self, degree: int, coefficients: MutableSequence[float]) -> None: if len(coefficients) != degree + 1: raise ValueError( "The number of coefficients should be equal to the degree + 1." ) self.coefficients: list[float] = list(coefficients) self.degree = degree def __add__(self, polynomial_2: Polynomial) -> Polynomial: if self.degree > polynomial_2.degree: coefficients = self.coefficients[:] for i in range(polynomial_2.degree + 1): coefficients[i] += polynomial_2.coefficients[i] return Polynomial(self.degree, coefficients) else: coefficients = polynomial_2.coefficients[:] for i in range(self.degree + 1): coefficients[i] += self.coefficients[i] return Polynomial(polynomial_2.degree, coefficients) def __sub__(self, polynomial_2: Polynomial) -> Polynomial: return self + polynomial_2 * Polynomial(0, [-1]) def __neg__(self) -> Polynomial: return Polynomial(self.degree, [-c for c in self.coefficients]) def __mul__(self, polynomial_2: Polynomial) -> Polynomial: coefficients: list[float] = [0] * (self.degree + polynomial_2.degree + 1) for i in range(self.degree + 1): for j in range(polynomial_2.degree + 1): coefficients[i + j] += ( self.coefficients[i] * polynomial_2.coefficients[j] ) return Polynomial(self.degree + polynomial_2.degree, coefficients) def evaluate(self, substitution: float) -> float: result: int | float = 0 for i in range(self.degree + 1): result += self.coefficients[i] * (substitution**i) return result def __str__(self) -> str: polynomial = "" for i in range(self.degree, -1, -1): if self.coefficients[i] == 0: continue elif self.coefficients[i] > 0: if polynomial: polynomial += " + " else: polynomial += " - " if i == 0: polynomial += str(abs(self.coefficients[i])) elif i == 1: polynomial += str(abs(self.coefficients[i])) + "x" else: polynomial += str(abs(self.coefficients[i])) + "x^" + str(i) return polynomial def __repr__(self) -> str: return self.__str__() def derivative(self) -> Polynomial: coefficients: list[float] = [0] * self.degree for i in range(self.degree): coefficients[i] = self.coefficients[i + 1] * (i + 1) return Polynomial(self.degree - 1, coefficients) def integral(self, constant: float = 0) -> Polynomial: coefficients: list[float] = [0] * (self.degree + 2) coefficients[0] = constant for i in range(self.degree + 1): coefficients[i + 1] = self.coefficients[i] / (i + 1) return Polynomial(self.degree + 1, coefficients) def __eq__(self, polynomial_2: object) -> bool: if not isinstance(polynomial_2, Polynomial): return False if self.degree != polynomial_2.degree: return False for i in range(self.degree + 1): if self.coefficients[i] != polynomial_2.coefficients[i]: return False return True def __ne__(self, polynomial_2: object) -> bool: return not self.__eq__(polynomial_2)
--- +++ @@ -1,3 +1,11 @@+""" + +This module implements a single indeterminate polynomials class +with some basic operations + +Reference: https://en.wikipedia.org/wiki/Polynomial + +""" from __future__ import annotations @@ -6,6 +14,15 @@ class Polynomial: def __init__(self, degree: int, coefficients: MutableSequence[float]) -> None: + """ + The coefficients should be in order of degree, from smallest to largest. + >>> p = Polynomial(2, [1, 2, 3]) + >>> p = Polynomial(2, [1, 2, 3, 4]) + Traceback (most recent call last): + ... + ValueError: The number of coefficients should be equal to the degree + 1. + + """ if len(coefficients) != degree + 1: raise ValueError( "The number of coefficients should be equal to the degree + 1." @@ -15,6 +32,13 @@ self.degree = degree def __add__(self, polynomial_2: Polynomial) -> Polynomial: + """ + Polynomial addition + >>> p = Polynomial(2, [1, 2, 3]) + >>> q = Polynomial(2, [1, 2, 3]) + >>> p + q + 6x^2 + 4x + 2 + """ if self.degree > polynomial_2.degree: coefficients = self.coefficients[:] @@ -28,12 +52,32 @@ return Polynomial(polynomial_2.degree, coefficients) def __sub__(self, polynomial_2: Polynomial) -> Polynomial: + """ + Polynomial subtraction + >>> p = Polynomial(2, [1, 2, 4]) + >>> q = Polynomial(2, [1, 2, 3]) + >>> p - q + 1x^2 + """ return self + polynomial_2 * Polynomial(0, [-1]) def __neg__(self) -> Polynomial: + """ + Polynomial negation + >>> p = Polynomial(2, [1, 2, 3]) + >>> -p + - 3x^2 - 2x - 1 + """ return Polynomial(self.degree, [-c for c in self.coefficients]) def __mul__(self, polynomial_2: Polynomial) -> Polynomial: + """ + Polynomial multiplication + >>> p = Polynomial(2, [1, 2, 3]) + >>> q = Polynomial(2, [1, 2, 3]) + >>> p * q + 9x^4 + 12x^3 + 10x^2 + 4x + 1 + """ coefficients: list[float] = [0] * (self.degree + polynomial_2.degree + 1) for i in range(self.degree + 1): for j in range(polynomial_2.degree + 1): @@ -44,12 +88,23 @@ return Polynomial(self.degree + polynomial_2.degree, coefficients) def evaluate(self, substitution: float) -> float: + """ + Evaluates the polynomial at x. + >>> p = Polynomial(2, [1, 2, 3]) + >>> p.evaluate(2) + 17 + """ result: int | float = 0 for i in range(self.degree + 1): result += self.coefficients[i] * (substitution**i) return result def __str__(self) -> str: + """ + >>> p = Polynomial(2, [1, 2, 3]) + >>> print(p) + 3x^2 + 2x + 1 + """ polynomial = "" for i in range(self.degree, -1, -1): if self.coefficients[i] == 0: @@ -70,15 +125,32 @@ return polynomial def __repr__(self) -> str: + """ + >>> p = Polynomial(2, [1, 2, 3]) + >>> p + 3x^2 + 2x + 1 + """ return self.__str__() def derivative(self) -> Polynomial: + """ + Returns the derivative of the polynomial. + >>> p = Polynomial(2, [1, 2, 3]) + >>> p.derivative() + 6x + 2 + """ coefficients: list[float] = [0] * self.degree for i in range(self.degree): coefficients[i] = self.coefficients[i + 1] * (i + 1) return Polynomial(self.degree - 1, coefficients) def integral(self, constant: float = 0) -> Polynomial: + """ + Returns the integral of the polynomial. + >>> p = Polynomial(2, [1, 2, 3]) + >>> p.integral() + 1.0x^3 + 1.0x^2 + 1.0x + """ coefficients: list[float] = [0] * (self.degree + 2) coefficients[0] = constant for i in range(self.degree + 1): @@ -86,6 +158,13 @@ return Polynomial(self.degree + 1, coefficients) def __eq__(self, polynomial_2: object) -> bool: + """ + Checks if two polynomials are equal. + >>> p = Polynomial(2, [1, 2, 3]) + >>> q = Polynomial(2, [1, 2, 3]) + >>> p == q + True + """ if not isinstance(polynomial_2, Polynomial): return False @@ -99,4 +178,11 @@ return True def __ne__(self, polynomial_2: object) -> bool: - return not self.__eq__(polynomial_2)+ """ + Checks if two polynomials are not equal. + >>> p = Polynomial(2, [1, 2, 3]) + >>> q = Polynomial(2, [1, 2, 3]) + >>> p != q + False + """ + return not self.__eq__(polynomial_2)
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/maths/polynomials/single_indeterminate_operations.py
Create docstrings for API functions
def solution() -> int: return next( iter( [ a * b * (1000 - a - b) for a in range(1, 999) for b in range(a, 999) if (a * a + b * b == (1000 - a - b) ** 2) ] ) ) if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,32 @@+""" +Project Euler Problem 9: https://projecteuler.net/problem=9 + +Special Pythagorean triplet + +A Pythagorean triplet is a set of three natural numbers, a < b < c, for which, + + a^2 + b^2 = c^2 + +For example, 3^2 + 4^2 = 9 + 16 = 25 = 5^2. + +There exists exactly one Pythagorean triplet for which a + b + c = 1000. +Find the product a*b*c. + +References: + - https://en.wikipedia.org/wiki/Pythagorean_triple +""" def solution() -> int: + """ + Returns the product of a,b,c which are Pythagorean Triplet that satisfies + the following: + 1. a**2 + b**2 = c**2 + 2. a + b + c = 1000 + + >>> solution() + 31875000 + """ return next( iter( @@ -15,4 +41,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_009/sol3.py
Add docstrings following best practices
def solution(n: int = 1000) -> int: product = -1 candidate = 0 for a in range(1, n // 3): # Solving the two equations a**2+b**2=c**2 and a+b+c=N eliminating c b = (n * n - 2 * a * n) // (2 * n - 2 * a) c = n - a - b if c * c == (a * a + b * b): candidate = a * b * c product = max(product, candidate) return product if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,35 @@+""" +Project Euler Problem 9: https://projecteuler.net/problem=9 + +Special Pythagorean triplet + +A Pythagorean triplet is a set of three natural numbers, a < b < c, for which, + + a^2 + b^2 = c^2 + +For example, 3^2 + 4^2 = 9 + 16 = 25 = 5^2. + +There exists exactly one Pythagorean triplet for which a + b + c = 1000. +Find the product a*b*c. + +References: + - https://en.wikipedia.org/wiki/Pythagorean_triple +""" def solution(n: int = 1000) -> int: + """ + Return the product of a,b,c which are Pythagorean Triplet that satisfies + the following: + 1. a < b < c + 2. a**2 + b**2 = c**2 + 3. a + b + c = n + + >>> solution(36) + 1620 + >>> solution(126) + 66780 + """ product = -1 candidate = 0 @@ -15,4 +44,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_009/sol2.py
Add standardized docstrings across the file
def count_divisors(n): n_divisors = 1 i = 2 while i * i <= n: multiplicity = 0 while n % i == 0: n //= i multiplicity += 1 n_divisors *= multiplicity + 1 i += 1 if n > 1: n_divisors *= 2 return n_divisors def solution(): t_num = 1 i = 1 while True: i += 1 t_num += i if count_divisors(t_num) > 500: break return t_num if __name__ == "__main__": print(solution())
--- +++ @@ -1,3 +1,26 @@+""" +Highly divisible triangular numbers +Problem 12 +The sequence of triangle numbers is generated by adding the natural numbers. So +the 7th triangle number would be 1 + 2 + 3 + 4 + 5 + 6 + 7 = 28. The first ten +terms would be: + +1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ... + +Let us list the factors of the first seven triangle numbers: + + 1: 1 + 3: 1,3 + 6: 1,2,3,6 +10: 1,2,5,10 +15: 1,3,5,15 +21: 1,3,7,21 +28: 1,2,4,7,14,28 +We can see that 28 is the first triangle number to have over five divisors. + +What is the value of the first triangle number to have over five hundred +divisors? +""" def count_divisors(n): @@ -16,6 +39,12 @@ def solution(): + """Returns the value of the first triangle number to have over five hundred + divisors. + + >>> solution() + 76576500 + """ t_num = 1 i = 1 @@ -30,4 +59,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_012/sol1.py
Add documentation for all methods
import os def largest_product(grid): n_columns = len(grid[0]) n_rows = len(grid) largest = 0 lr_diag_product = 0 rl_diag_product = 0 # Check vertically, horizontally, diagonally at the same time (only works # for nxn grid) for i in range(n_columns): for j in range(n_rows - 3): vert_product = grid[j][i] * grid[j + 1][i] * grid[j + 2][i] * grid[j + 3][i] horz_product = grid[i][j] * grid[i][j + 1] * grid[i][j + 2] * grid[i][j + 3] # Left-to-right diagonal (\) product if i < n_columns - 3: lr_diag_product = ( grid[i][j] * grid[i + 1][j + 1] * grid[i + 2][j + 2] * grid[i + 3][j + 3] ) # Right-to-left diagonal(/) product if i > 2: rl_diag_product = ( grid[i][j] * grid[i - 1][j + 1] * grid[i - 2][j + 2] * grid[i - 3][j + 3] ) max_product = max( vert_product, horz_product, lr_diag_product, rl_diag_product ) largest = max(largest, max_product) return largest def solution(): grid = [] with open(os.path.dirname(__file__) + "/grid.txt") as file: for line in file: grid.append(line.strip("\n").split(" ")) grid = [[int(i) for i in grid[j]] for j in range(len(grid))] return largest_product(grid) if __name__ == "__main__": print(solution())
--- +++ @@ -1,3 +1,28 @@+""" +What is the greatest product of four adjacent numbers (horizontally, +vertically, or diagonally) in this 20x20 array? + +08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08 +49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00 +81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65 +52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 36 91 +22 31 16 71 51 67 63 89 41 92 36 54 22 40 40 28 66 33 13 80 +24 47 32 60 99 03 45 02 44 75 33 53 78 36 84 20 35 17 12 50 +32 98 81 28 64 23 67 10 26 38 40 67 59 54 70 66 18 38 64 70 +67 26 20 68 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21 +24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72 +21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95 +78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92 +16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57 +86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58 +19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40 +04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66 +88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69 +04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36 +20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16 +20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54 +01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48 +""" import os @@ -44,6 +69,12 @@ def solution(): + """Returns the greatest product of four adjacent numbers (horizontally, + vertically, or diagonally). + + >>> solution() + 70600674 + """ grid = [] with open(os.path.dirname(__file__) + "/grid.txt") as file: for line in file: @@ -55,4 +86,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_011/sol1.py
Document helper functions with docstrings
def triangle_number_generator(): for n in range(1, 1000000): yield n * (n + 1) // 2 def count_divisors(n): divisors_count = 1 i = 2 while i * i <= n: multiplicity = 0 while n % i == 0: n //= i multiplicity += 1 divisors_count *= multiplicity + 1 i += 1 if n > 1: divisors_count *= 2 return divisors_count def solution(): return next(i for i in triangle_number_generator() if count_divisors(i) > 500) if __name__ == "__main__": print(solution())
--- +++ @@ -1,3 +1,26 @@+""" +Highly divisible triangular numbers +Problem 12 +The sequence of triangle numbers is generated by adding the natural numbers. So +the 7th triangle number would be 1 + 2 + 3 + 4 + 5 + 6 + 7 = 28. The first ten +terms would be: + +1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ... + +Let us list the factors of the first seven triangle numbers: + + 1: 1 + 3: 1,3 + 6: 1,2,3,6 +10: 1,2,5,10 +15: 1,3,5,15 +21: 1,3,7,21 +28: 1,2,4,7,14,28 +We can see that 28 is the first triangle number to have over five divisors. + +What is the value of the first triangle number to have over five hundred +divisors? +""" def triangle_number_generator(): @@ -21,8 +44,14 @@ def solution(): + """Returns the value of the first triangle number to have over five hundred + divisors. + + >>> solution() + 76576500 + """ return next(i for i in triangle_number_generator() if count_divisors(i) > 500) if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_012/sol2.py
Add docstrings for production code
import math def is_prime(number: int) -> bool: if 1 < number < 4: # 2 and 3 are primes return True elif number < 2 or number % 2 == 0 or number % 3 == 0: # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes return False # All primes number are in format of 6k +/- 1 for i in range(5, int(math.sqrt(number) + 1), 6): if number % i == 0 or number % (i + 2) == 0: return False return True def solution(n: int = 2000000) -> int: return sum(num for num in range(3, n, 2) if is_prime(num)) + 2 if n > 2 else 0 if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,8 +1,38 @@+""" +Project Euler Problem 10: https://projecteuler.net/problem=10 + +Summation of primes + +The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17. + +Find the sum of all the primes below two million. + +References: + - https://en.wikipedia.org/wiki/Prime_number +""" import math def is_prime(number: int) -> bool: + """Checks to see if a number is a prime in O(sqrt(n)). + A number is prime if it has exactly two factors: 1 and itself. + Returns boolean representing primality of given number num (i.e., if the + result is true, then the number is indeed prime else it is not). + + >>> is_prime(2) + True + >>> is_prime(3) + True + >>> is_prime(27) + False + >>> is_prime(2999) + True + >>> is_prime(0) + False + >>> is_prime(1) + False + """ if 1 < number < 4: # 2 and 3 are primes @@ -19,9 +49,21 @@ def solution(n: int = 2000000) -> int: + """ + Returns the sum of all the primes below n. + + >>> solution(1000) + 76127 + >>> solution(5000) + 1548136 + >>> solution(10000) + 5736396 + >>> solution(7) + 10 + """ return sum(num for num in range(3, n, 2) if is_prime(num)) + 2 if n > 2 else 0 if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_010/sol1.py
Provide clean and structured docstrings
def solution() -> int: for a in range(300): for b in range(a + 1, 400): for c in range(b + 1, 500): if (a + b + c) == 1000 and (a**2) + (b**2) == (c**2): return a * b * c return -1 def solution_fast() -> int: for a in range(300): for b in range(400): c = 1000 - a - b if a < b < c and (a**2) + (b**2) == (c**2): return a * b * c return -1 def benchmark() -> None: import timeit print( timeit.timeit("solution()", setup="from __main__ import solution", number=1000) ) print( timeit.timeit( "solution_fast()", setup="from __main__ import solution_fast", number=1000 ) ) if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,33 @@+""" +Project Euler Problem 9: https://projecteuler.net/problem=9 + +Special Pythagorean triplet + +A Pythagorean triplet is a set of three natural numbers, a < b < c, for which, + + a^2 + b^2 = c^2 + +For example, 3^2 + 4^2 = 9 + 16 = 25 = 5^2. + +There exists exactly one Pythagorean triplet for which a + b + c = 1000. +Find the product a*b*c. + +References: + - https://en.wikipedia.org/wiki/Pythagorean_triple +""" def solution() -> int: + """ + Returns the product of a,b,c which are Pythagorean Triplet that satisfies + the following: + 1. a < b < c + 2. a**2 + b**2 = c**2 + 3. a + b + c = 1000 + + >>> solution() + 31875000 + """ for a in range(300): for b in range(a + 1, 400): @@ -12,6 +39,16 @@ def solution_fast() -> int: + """ + Returns the product of a,b,c which are Pythagorean Triplet that satisfies + the following: + 1. a < b < c + 2. a**2 + b**2 = c**2 + 3. a + b + c = 1000 + + >>> solution_fast() + 31875000 + """ for a in range(300): for b in range(400): @@ -23,6 +60,9 @@ def benchmark() -> None: + """ + Benchmark code comparing two different version function. + """ import timeit print( @@ -36,4 +76,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_009/sol1.py
Generate NumPy-style docstrings
def solution(n: int = 4000000) -> int: if n <= 1: return 0 a = 0 b = 2 count = 0 while 4 * b + a <= n: a, b = b, 4 * b + a count += a return count + b if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,37 @@+""" +Project Euler Problem 2: https://projecteuler.net/problem=2 + +Even Fibonacci Numbers + +Each new term in the Fibonacci sequence is generated by adding the previous +two terms. By starting with 1 and 2, the first 10 terms will be: + +1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ... + +By considering the terms in the Fibonacci sequence whose values do not exceed +four million, find the sum of the even-valued terms. + +References: + - https://en.wikipedia.org/wiki/Fibonacci_number +""" def solution(n: int = 4000000) -> int: + """ + Returns the sum of all even fibonacci sequence elements that are lower + or equal to n. + + >>> solution(10) + 10 + >>> solution(15) + 10 + >>> solution(2) + 2 + >>> solution(1) + 0 + >>> solution(34) + 44 + """ if n <= 1: return 0 @@ -14,4 +45,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_002/sol3.py
Create Google-style docstrings for my code
def solution(n: int = 2000000) -> int: primality_list = [0 for i in range(n + 1)] primality_list[0] = 1 primality_list[1] = 1 for i in range(2, int(n**0.5) + 1): if primality_list[i] == 0: for j in range(i * i, n + 1, i): primality_list[j] = 1 sum_of_primes = 0 for i in range(n): if primality_list[i] == 0: sum_of_primes += i return sum_of_primes if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,46 @@+""" +Project Euler Problem 10: https://projecteuler.net/problem=10 + +Summation of primes + +The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17. + +Find the sum of all the primes below two million. + +References: + - https://en.wikipedia.org/wiki/Prime_number + - https://en.wikipedia.org/wiki/Sieve_of_Eratosthenes +""" def solution(n: int = 2000000) -> int: + """ + Returns the sum of all the primes below n using Sieve of Eratosthenes: + + The sieve of Eratosthenes is one of the most efficient ways to find all primes + smaller than n when n is smaller than 10 million. Only for positive numbers. + + >>> solution(1000) + 76127 + >>> solution(5000) + 1548136 + >>> solution(10000) + 5736396 + >>> solution(7) + 10 + >>> solution(7.1) # doctest: +ELLIPSIS + Traceback (most recent call last): + ... + TypeError: 'float' object cannot be interpreted as an integer + >>> solution(-7) # doctest: +ELLIPSIS + Traceback (most recent call last): + ... + IndexError: list assignment index out of range + >>> solution("seven") # doctest: +ELLIPSIS + Traceback (most recent call last): + ... + TypeError: can only concatenate str (not "int") to str + """ primality_list = [0 for i in range(n + 1)] primality_list[0] = 1 @@ -18,4 +58,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_010/sol3.py
Add docstrings to meet PEP guidelines
import math from collections.abc import Iterator from itertools import takewhile def is_prime(number: int) -> bool: if 1 < number < 4: # 2 and 3 are primes return True elif number < 2 or number % 2 == 0 or number % 3 == 0: # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes return False # All primes number are in format of 6k +/- 1 for i in range(5, int(math.sqrt(number) + 1), 6): if number % i == 0 or number % (i + 2) == 0: return False return True def prime_generator() -> Iterator[int]: num = 2 while True: if is_prime(num): yield num num += 1 def solution(n: int = 2000000) -> int: return sum(takewhile(lambda x: x < n, prime_generator())) if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,3 +1,15 @@+""" +Project Euler Problem 10: https://projecteuler.net/problem=10 + +Summation of primes + +The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17. + +Find the sum of all the primes below two million. + +References: + - https://en.wikipedia.org/wiki/Prime_number +""" import math from collections.abc import Iterator @@ -5,6 +17,24 @@ def is_prime(number: int) -> bool: + """Checks to see if a number is a prime in O(sqrt(n)). + A number is prime if it has exactly two factors: 1 and itself. + Returns boolean representing primality of given number num (i.e., if the + result is true, then the number is indeed prime else it is not). + + >>> is_prime(2) + True + >>> is_prime(3) + True + >>> is_prime(27) + False + >>> is_prime(2999) + True + >>> is_prime(0) + False + >>> is_prime(1) + False + """ if 1 < number < 4: # 2 and 3 are primes @@ -21,6 +51,9 @@ def prime_generator() -> Iterator[int]: + """ + Generate a list sequence of prime numbers + """ num = 2 while True: @@ -30,9 +63,21 @@ def solution(n: int = 2000000) -> int: + """ + Returns the sum of all the primes below n. + + >>> solution(1000) + 76127 + >>> solution(5000) + 1548136 + >>> solution(10000) + 5736396 + >>> solution(7) + 10 + """ return sum(takewhile(lambda x: x < n, prime_generator())) if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_010/sol2.py
Write docstrings for algorithm functions
import os def solution(): file_path = os.path.join(os.path.dirname(__file__), "num.txt") with open(file_path) as file_hand: return str(sum(int(line) for line in file_hand))[:10] if __name__ == "__main__": print(solution())
--- +++ @@ -1,12 +1,26 @@+""" +Problem 13: https://projecteuler.net/problem=13 + +Problem Statement: +Work out the first ten digits of the sum of the following one-hundred 50-digit +numbers. +""" import os def solution(): + """ + Returns the first ten digits of the sum of the array elements + from the file num.txt + + >>> solution() + '5537376230' + """ file_path = os.path.join(os.path.dirname(__file__), "num.txt") with open(file_path) as file_hand: return str(sum(int(line) for line in file_hand))[:10] if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_013/sol1.py
Add docstrings that explain purpose and usage
from __future__ import annotations COLLATZ_SEQUENCE_LENGTHS = {1: 1} def collatz_sequence_length(n: int) -> int: if n in COLLATZ_SEQUENCE_LENGTHS: return COLLATZ_SEQUENCE_LENGTHS[n] next_n = n // 2 if n % 2 == 0 else 3 * n + 1 sequence_length = collatz_sequence_length(next_n) + 1 COLLATZ_SEQUENCE_LENGTHS[n] = sequence_length return sequence_length def solution(n: int = 1000000) -> int: result = max((collatz_sequence_length(i), i) for i in range(1, n)) return result[1] if __name__ == "__main__": print(solution(int(input().strip())))
--- +++ @@ -1,3 +1,30 @@+""" +Problem 14: https://projecteuler.net/problem=14 + +Collatz conjecture: start with any positive integer n. Next term obtained from +the previous term as follows: + +If the previous term is even, the next term is one half the previous term. +If the previous term is odd, the next term is 3 times the previous term plus 1. +The conjecture states the sequence will always reach 1 regardless of starting +n. + +Problem Statement: +The following iterative sequence is defined for the set of positive integers: + + n → n/2 (n is even) + n → 3n + 1 (n is odd) + +Using the rule above and starting with 13, we generate the following sequence: + + 13 → 40 → 20 → 10 → 5 → 16 → 8 → 4 → 2 → 1 + +It can be seen that this sequence (starting at 13 and finishing at 1) contains +10 terms. Although it has not been proved yet (Collatz Problem), it is thought +that all starting numbers finish at 1. + +Which starting number, under one million, produces the longest chain? +""" from __future__ import annotations @@ -5,6 +32,7 @@ def collatz_sequence_length(n: int) -> int: + """Returns the Collatz sequence length for n.""" if n in COLLATZ_SEQUENCE_LENGTHS: return COLLATZ_SEQUENCE_LENGTHS[n] next_n = n // 2 if n % 2 == 0 else 3 * n + 1 @@ -14,10 +42,21 @@ def solution(n: int = 1000000) -> int: + """Returns the number under n that generates the longest Collatz sequence. + + >>> solution(1000000) + 837799 + >>> solution(200) + 171 + >>> solution(5000) + 3711 + >>> solution(15000) + 13255 + """ result = max((collatz_sequence_length(i), i) for i in range(1, n)) return result[1] if __name__ == "__main__": - print(solution(int(input().strip())))+ print(solution(int(input().strip())))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_014/sol2.py
Add docstrings for utility scripts
def solution(n: int = 1000000) -> int: largest_number = 1 pre_counter = 1 counters = {1: 1} for input1 in range(2, n): counter = 0 number = input1 while True: if number in counters: counter += counters[number] break if number % 2 == 0: number //= 2 counter += 1 else: number = (3 * number) + 1 counter += 1 if input1 not in counters: counters[input1] = counter if counter > pre_counter: largest_number = input1 pre_counter = counter return largest_number if __name__ == "__main__": print(solution(int(input().strip())))
--- +++ @@ -1,6 +1,39 @@+""" +Problem 14: https://projecteuler.net/problem=14 + +Problem Statement: +The following iterative sequence is defined for the set of positive integers: + + n → n/2 (n is even) + n → 3n + 1 (n is odd) + +Using the rule above and starting with 13, we generate the following sequence: + + 13 → 40 → 20 → 10 → 5 → 16 → 8 → 4 → 2 → 1 + +It can be seen that this sequence (starting at 13 and finishing at 1) contains +10 terms. Although it has not been proved yet (Collatz Problem), it is thought +that all starting numbers finish at 1. + +Which starting number, under one million, produces the longest chain? +""" def solution(n: int = 1000000) -> int: + """Returns the number under n that generates the longest sequence using the + formula: + n → n/2 (n is even) + n → 3n + 1 (n is odd) + + >>> solution(1000000) + 837799 + >>> solution(200) + 171 + >>> solution(5000) + 3711 + >>> solution(15000) + 13255 + """ largest_number = 1 pre_counter = 1 counters = {1: 1} @@ -30,4 +63,4 @@ if __name__ == "__main__": - print(solution(int(input().strip())))+ print(solution(int(input().strip())))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_014/sol1.py
Replace inline comments with docstrings
def solution(n: int = 20) -> int: counts = [[1 for _ in range(n + 1)] for _ in range(n + 1)] for i in range(1, n + 1): for j in range(1, n + 1): counts[i][j] = counts[i - 1][j] + counts[i][j - 1] return counts[n][n] if __name__ == "__main__": print(solution())
--- +++ @@ -1,6 +1,23 @@+""" +Problem 15: https://projecteuler.net/problem=15 + +Starting in the top left corner of a 2x2 grid, and only being able to move to +the right and down, there are exactly 6 routes to the bottom right corner. +How many such routes are there through a 20x20 grid? +""" def solution(n: int = 20) -> int: + """ + Solve by explicitly counting the paths with dynamic programming. + + >>> solution(6) + 924 + >>> solution(2) + 6 + >>> solution(1) + 2 + """ counts = [[1 for _ in range(n + 1)] for _ in range(n + 1)] @@ -12,4 +29,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_015/sol2.py
Add docstrings including usage examples
from math import factorial def solution(n: int = 20) -> int: n = 2 * n # middle entry of odd rows starting at row 3 is the solution for n = 1, # 2, 3,... k = n // 2 return int(factorial(n) / (factorial(k) * factorial(n - k))) if __name__ == "__main__": import sys if len(sys.argv) == 1: print(solution(20)) else: try: n = int(sys.argv[1]) print(solution(n)) except ValueError: print("Invalid entry - please enter a number.")
--- +++ @@ -1,8 +1,30 @@+""" +Problem 15: https://projecteuler.net/problem=15 + +Starting in the top left corner of a 2x2 grid, and only being able to move to +the right and down, there are exactly 6 routes to the bottom right corner. +How many such routes are there through a 20x20 grid? +""" from math import factorial def solution(n: int = 20) -> int: + """ + Returns the number of paths possible in a n x n grid starting at top left + corner going to bottom right corner and being able to move right and down + only. + >>> solution(25) + 126410606437752 + >>> solution(23) + 8233430727600 + >>> solution(20) + 137846528820 + >>> solution(15) + 155117520 + >>> solution(1) + 2 + """ n = 2 * n # middle entry of odd rows starting at row 3 is the solution for n = 1, # 2, 3,... k = n // 2 @@ -20,4 +42,4 @@ n = int(sys.argv[1]) print(solution(n)) except ValueError: - print("Invalid entry - please enter a number.")+ print("Invalid entry - please enter a number.")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_015/sol1.py
Write docstrings describing each step
def solution(power: int = 1000) -> int: num = 2**power string_num = str(num) list_num = list(string_num) sum_of_num = 0 for i in list_num: sum_of_num += int(i) return sum_of_num if __name__ == "__main__": power = int(input("Enter the power of 2: ").strip()) print("2 ^ ", power, " = ", 2**power) result = solution(power) print("Sum of the digits is: ", result)
--- +++ @@ -1,6 +1,23 @@+""" +Problem 16: https://projecteuler.net/problem=16 + +2^15 = 32768 and the sum of its digits is 3 + 2 + 7 + 6 + 8 = 26. + +What is the sum of the digits of the number 2^1000? +""" def solution(power: int = 1000) -> int: + """Returns the sum of the digits of the number 2^power. + >>> solution(1000) + 1366 + >>> solution(50) + 76 + >>> solution(20) + 31 + >>> solution(15) + 26 + """ num = 2**power string_num = str(num) list_num = list(string_num) @@ -16,4 +33,4 @@ power = int(input("Enter the power of 2: ").strip()) print("2 ^ ", power, " = ", 2**power) result = solution(power) - print("Sum of the digits is: ", result)+ print("Sum of the digits is: ", result)
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_016/sol1.py
Add structured docstrings to improve clarity
import os def solution(): with open(os.path.dirname(__file__) + "/grid.txt") as f: grid = [] for _ in range(20): grid.append([int(x) for x in f.readline().split()]) maximum = 0 # right for i in range(20): for j in range(17): temp = grid[i][j] * grid[i][j + 1] * grid[i][j + 2] * grid[i][j + 3] maximum = max(maximum, temp) # down for i in range(17): for j in range(20): temp = grid[i][j] * grid[i + 1][j] * grid[i + 2][j] * grid[i + 3][j] maximum = max(maximum, temp) # diagonal 1 for i in range(17): for j in range(17): temp = ( grid[i][j] * grid[i + 1][j + 1] * grid[i + 2][j + 2] * grid[i + 3][j + 3] ) maximum = max(maximum, temp) # diagonal 2 for i in range(17): for j in range(3, 20): temp = ( grid[i][j] * grid[i + 1][j - 1] * grid[i + 2][j - 2] * grid[i + 3][j - 3] ) maximum = max(maximum, temp) return maximum if __name__ == "__main__": print(solution())
--- +++ @@ -1,8 +1,39 @@+""" +What is the greatest product of four adjacent numbers (horizontally, +vertically, or diagonally) in this 20x20 array? + +08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08 +49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00 +81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65 +52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 36 91 +22 31 16 71 51 67 63 89 41 92 36 54 22 40 40 28 66 33 13 80 +24 47 32 60 99 03 45 02 44 75 33 53 78 36 84 20 35 17 12 50 +32 98 81 28 64 23 67 10 26 38 40 67 59 54 70 66 18 38 64 70 +67 26 20 68 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21 +24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72 +21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95 +78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92 +16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57 +86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58 +19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40 +04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66 +88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69 +04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36 +20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16 +20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54 +01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48 +""" import os def solution(): + """Returns the greatest product of four adjacent numbers (horizontally, + vertically, or diagonally). + + >>> solution() + 70600674 + """ with open(os.path.dirname(__file__) + "/grid.txt") as f: grid = [] for _ in range(20): @@ -47,4 +78,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_011/sol2.py
Generate consistent docstrings
def solution(power: int = 1000) -> int: n = 2**power r = 0 while n: r, n = r + n % 10, n // 10 return r if __name__ == "__main__": print(solution(int(str(input()).strip())))
--- +++ @@ -1,6 +1,24 @@+""" +Problem 16: https://projecteuler.net/problem=16 + +2^15 = 32768 and the sum of its digits is 3 + 2 + 7 + 6 + 8 = 26. + +What is the sum of the digits of the number 2^1000? +""" def solution(power: int = 1000) -> int: + """Returns the sum of the digits of the number 2^power. + + >>> solution(1000) + 1366 + >>> solution(50) + 76 + >>> solution(20) + 31 + >>> solution(15) + 26 + """ n = 2**power r = 0 while n: @@ -9,4 +27,4 @@ if __name__ == "__main__": - print(solution(int(str(input()).strip())))+ print(solution(int(str(input()).strip())))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_016/sol2.py
Generate consistent docstrings
import os def solution(): script_dir = os.path.dirname(os.path.realpath(__file__)) triangle = os.path.join(script_dir, "triangle.txt") with open(triangle) as f: triangle = f.readlines() a = [[int(y) for y in x.rstrip("\r\n").split(" ")] for x in triangle] for i in range(1, len(a)): for j in range(len(a[i])): number1 = a[i - 1][j] if j != len(a[i - 1]) else 0 number2 = a[i - 1][j - 1] if j > 0 else 0 a[i][j] += max(number1, number2) return max(a[-1]) if __name__ == "__main__": print(solution())
--- +++ @@ -1,8 +1,44 @@+""" +By starting at the top of the triangle below and moving to adjacent numbers on +the row below, the maximum total from top to bottom is 23. + +3 +7 4 +2 4 6 +8 5 9 3 + +That is, 3 + 7 + 4 + 9 = 23. + +Find the maximum total from top to bottom of the triangle below: + +75 +95 64 +17 47 82 +18 35 87 10 +20 04 82 47 65 +19 01 23 75 03 34 +88 02 77 73 07 63 67 +99 65 04 28 06 16 70 92 +41 41 26 56 83 40 80 70 33 +41 48 72 33 47 32 37 16 94 29 +53 71 44 65 25 43 91 52 97 51 14 +70 11 33 28 77 73 17 78 39 68 17 57 +91 71 52 38 17 14 91 43 58 50 27 29 48 +63 66 04 68 89 53 67 30 73 16 69 87 40 31 +04 62 98 27 23 09 70 98 73 93 38 53 60 04 23 +""" import os def solution(): + """ + Finds the maximum total in a triangle as described by the problem statement + above. + + >>> solution() + 1074 + """ script_dir = os.path.dirname(os.path.realpath(__file__)) triangle = os.path.join(script_dir, "triangle.txt") @@ -20,4 +56,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_018/solution.py
Write docstrings for utility functions
from math import factorial def solution(num: int = 100) -> int: return sum(int(x) for x in str(factorial(num))) if __name__ == "__main__": print(solution(int(input("Enter the Number: ").strip())))
--- +++ @@ -1,10 +1,36 @@+""" +Problem 20: https://projecteuler.net/problem=20 + +n! means n x (n - 1) x ... x 3 x 2 x 1 + +For example, 10! = 10 x 9 x ... x 3 x 2 x 1 = 3628800, +and the sum of the digits in the number 10! is 3 + 6 + 2 + 8 + 8 + 0 + 0 = 27. + +Find the sum of the digits in the number 100! +""" from math import factorial def solution(num: int = 100) -> int: + """Returns the sum of the digits in the factorial of num + >>> solution(100) + 648 + >>> solution(50) + 216 + >>> solution(10) + 27 + >>> solution(5) + 3 + >>> solution(3) + 6 + >>> solution(2) + 2 + >>> solution(1) + 1 + """ return sum(int(x) for x in str(factorial(num))) if __name__ == "__main__": - print(solution(int(input("Enter the Number: ").strip())))+ print(solution(int(input("Enter the Number: ").strip())))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_020/sol2.py
Document all public functions with docstrings
def factorial(num: int) -> int: fact = 1 for i in range(1, num + 1): fact *= i return fact def split_and_add(number: int) -> int: sum_of_digits = 0 while number > 0: last_digit = number % 10 sum_of_digits += last_digit number = number // 10 # Removing the last_digit from the given number return sum_of_digits def solution(num: int = 100) -> int: nfact = factorial(num) result = split_and_add(nfact) return result if __name__ == "__main__": print(solution(int(input("Enter the Number: ").strip())))
--- +++ @@ -1,6 +1,17 @@+""" +Problem 20: https://projecteuler.net/problem=20 + +n! means n x (n - 1) x ... x 3 x 2 x 1 + +For example, 10! = 10 x 9 x ... x 3 x 2 x 1 = 3628800, +and the sum of the digits in the number 10! is 3 + 6 + 2 + 8 + 8 + 0 + 0 = 27. + +Find the sum of the digits in the number 100! +""" def factorial(num: int) -> int: + """Find the factorial of a given number n""" fact = 1 for i in range(1, num + 1): fact *= i @@ -8,6 +19,7 @@ def split_and_add(number: int) -> int: + """Split number digits and add them.""" sum_of_digits = 0 while number > 0: last_digit = number % 10 @@ -17,10 +29,26 @@ def solution(num: int = 100) -> int: + """Returns the sum of the digits in the factorial of num + >>> solution(100) + 648 + >>> solution(50) + 216 + >>> solution(10) + 27 + >>> solution(5) + 3 + >>> solution(3) + 6 + >>> solution(2) + 2 + >>> solution(1) + 1 + """ nfact = factorial(num) result = split_and_add(nfact) return result if __name__ == "__main__": - print(solution(int(input("Enter the Number: ").strip())))+ print(solution(int(input("Enter the Number: ").strip())))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_020/sol1.py
Add docstrings with type hints explained
def solution(): days_per_month = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31] day = 6 month = 1 year = 1901 sundays = 0 while year < 2001: day += 7 if (year % 4 == 0 and year % 100 != 0) or (year % 400 == 0): if day > days_per_month[month - 1] and month != 2: month += 1 day = day - days_per_month[month - 2] elif day > 29 and month == 2: month += 1 day = day - 29 elif day > days_per_month[month - 1]: month += 1 day = day - days_per_month[month - 2] if month > 12: year += 1 month = 1 if year < 2001 and day == 1: sundays += 1 return sundays if __name__ == "__main__": print(solution())
--- +++ @@ -1,6 +1,33 @@+""" +Counting Sundays +Problem 19 + +You are given the following information, but you may prefer to do some research +for yourself. + +1 Jan 1900 was a Monday. +Thirty days has September, +April, June and November. +All the rest have thirty-one, +Saving February alone, +Which has twenty-eight, rain or shine. +And on leap years, twenty-nine. + +A leap year occurs on any year evenly divisible by 4, but not on a century +unless it is divisible by 400. + +How many Sundays fell on the first of the month during the twentieth century +(1 Jan 1901 to 31 Dec 2000)? +""" def solution(): + """Returns the number of mondays that fall on the first of the month during + the twentieth century (1 Jan 1901 to 31 Dec 2000)? + + >>> solution() + 171 + """ days_per_month = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31] day = 6 @@ -33,4 +60,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_019/sol1.py
Generate consistent docstrings
def solution(n: int = 1000) -> int: # number of letters in zero, one, two, ..., nineteen (0 for zero since it's # never said aloud) ones_counts = [0, 3, 3, 5, 4, 4, 3, 5, 5, 4, 3, 6, 6, 8, 8, 7, 7, 9, 8, 8] # number of letters in twenty, thirty, ..., ninety (0 for numbers less than # 20 due to inconsistency in teens) tens_counts = [0, 0, 6, 6, 5, 5, 5, 7, 6, 6] count = 0 for i in range(1, n + 1): if i < 1000: if i >= 100: # add number of letters for "n hundred" count += ones_counts[i // 100] + 7 if i % 100 != 0: # add number of letters for "and" if number is not multiple # of 100 count += 3 if 0 < i % 100 < 20: # add number of letters for one, two, three, ..., nineteen # (could be combined with below if not for inconsistency in # teens) count += ones_counts[i % 100] else: # add number of letters for twenty, twenty one, ..., ninety # nine count += ones_counts[i % 10] count += tens_counts[(i % 100 - i % 10) // 10] else: count += ones_counts[i // 1000] + 8 return count if __name__ == "__main__": print(solution(int(input().strip())))
--- +++ @@ -1,6 +1,29 @@+""" +Number letter counts +Problem 17: https://projecteuler.net/problem=17 + +If the numbers 1 to 5 are written out in words: one, two, three, four, five, +then there are 3 + 3 + 5 + 4 + 4 = 19 letters used in total. + +If all the numbers from 1 to 1000 (one thousand) inclusive were written out in +words, how many letters would be used? + + +NOTE: Do not count spaces or hyphens. For example, 342 (three hundred and +forty-two) contains 23 letters and 115 (one hundred and fifteen) contains 20 +letters. The use of "and" when writing out numbers is in compliance withBritish +usage. +""" def solution(n: int = 1000) -> int: + """Returns the number of letters used to write all numbers from 1 to n. + where n is lower or equals to 1000. + >>> solution(1000) + 21124 + >>> solution(5) + 19 + """ # number of letters in zero, one, two, ..., nineteen (0 for zero since it's # never said aloud) ones_counts = [0, 3, 3, 5, 4, 4, 3, 5, 5, 4, 3, 6, 6, 8, 8, 7, 7, 9, 8, 8] @@ -37,4 +60,4 @@ if __name__ == "__main__": - print(solution(int(input().strip())))+ print(solution(int(input().strip())))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_017/sol1.py
Add professional docstrings to my codebase
def solution(num: int = 100) -> int: fact = 1 result = 0 for i in range(1, num + 1): fact *= i for j in str(fact): result += int(j) return result if __name__ == "__main__": print(solution(int(input("Enter the Number: ").strip())))
--- +++ @@ -1,6 +1,32 @@+""" +Problem 20: https://projecteuler.net/problem=20 + +n! means n x (n - 1) x ... x 3 x 2 x 1 + +For example, 10! = 10 x 9 x ... x 3 x 2 x 1 = 3628800, +and the sum of the digits in the number 10! is 3 + 6 + 2 + 8 + 8 + 0 + 0 = 27. + +Find the sum of the digits in the number 100! +""" def solution(num: int = 100) -> int: + """Returns the sum of the digits in the factorial of num + >>> solution(100) + 648 + >>> solution(50) + 216 + >>> solution(10) + 27 + >>> solution(5) + 3 + >>> solution(3) + 6 + >>> solution(2) + 2 + >>> solution(1) + 1 + """ fact = 1 result = 0 for i in range(1, num + 1): @@ -13,4 +39,4 @@ if __name__ == "__main__": - print(solution(int(input("Enter the Number: ").strip())))+ print(solution(int(input("Enter the Number: ").strip())))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_020/sol4.py
Document this code for team use
from math import sqrt def sum_of_divisors(n: int) -> int: total = 0 for i in range(1, int(sqrt(n) + 1)): if n % i == 0 and i != sqrt(n): total += i + n // i elif i == sqrt(n): total += i return total - n def solution(n: int = 10000) -> int: total = sum( i for i in range(1, n) if sum_of_divisors(sum_of_divisors(i)) == i and sum_of_divisors(i) != i ) return total if __name__ == "__main__": print(solution(int(str(input()).strip())))
--- +++ @@ -1,3 +1,18 @@+""" +Amicable Numbers +Problem 21 + +Let d(n) be defined as the sum of proper divisors of n (numbers less than n +which divide evenly into n). +If d(a) = b and d(b) = a, where a ≠ b, then a and b are an amicable pair and +each of a and b are called amicable numbers. + +For example, the proper divisors of 220 are 1, 2, 4, 5, 10, 11, 20, 22, 44, 55 +and 110; therefore d(220) = 284. The proper divisors of 284 are 1, 2, 4, 71 and +142; so d(284) = 220. + +Evaluate the sum of all the amicable numbers under 10000. +""" from math import sqrt @@ -13,6 +28,19 @@ def solution(n: int = 10000) -> int: + """Returns the sum of all the amicable numbers under n. + + >>> solution(10000) + 31626 + >>> solution(5000) + 8442 + >>> solution(1000) + 504 + >>> solution(100) + 0 + >>> solution(50) + 0 + """ total = sum( i for i in range(1, n) @@ -22,4 +50,4 @@ if __name__ == "__main__": - print(solution(int(str(input()).strip())))+ print(solution(int(str(input()).strip())))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_021/sol1.py
Generate docstrings for exported functions
def solution(limit=28123): sum_divs = [1] * (limit + 1) for i in range(2, int(limit**0.5) + 1): sum_divs[i * i] += i for k in range(i + 1, limit // i + 1): sum_divs[k * i] += k + i abundants = set() res = 0 for n in range(1, limit + 1): if sum_divs[n] > n: abundants.add(n) if not any((n - a in abundants) for a in abundants): res += n return res if __name__ == "__main__": print(solution())
--- +++ @@ -1,6 +1,33 @@+""" +A perfect number is a number for which the sum of its proper divisors is exactly +equal to the number. For example, the sum of the proper divisors of 28 would be +1 + 2 + 4 + 7 + 14 = 28, which means that 28 is a perfect number. + +A number n is called deficient if the sum of its proper divisors is less than n +and it is called abundant if this sum exceeds n. + +As 12 is the smallest abundant number, 1 + 2 + 3 + 4 + 6 = 16, the smallest +number that can be written as the sum of two abundant numbers is 24. By +mathematical analysis, it can be shown that all integers greater than 28123 +can be written as the sum of two abundant numbers. However, this upper limit +cannot be reduced any further by analysis even though it is known that the +greatest number that cannot be expressed as the sum of two abundant numbers +is less than this limit. + +Find the sum of all the positive integers which cannot be written as the sum +of two abundant numbers. +""" def solution(limit=28123): + """ + Finds the sum of all the positive integers which cannot be written as + the sum of two abundant numbers + as described by the statement above. + + >>> solution() + 4179871 + """ sum_divs = [1] * (limit + 1) for i in range(2, int(limit**0.5) + 1): @@ -22,4 +49,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_023/sol1.py
Generate missing documentation strings
import os def solution(): with open(os.path.dirname(__file__) + "/p022_names.txt") as file: names = str(file.readlines()[0]) names = names.replace('"', "").split(",") names.sort() name_score = 0 total_score = 0 for i, name in enumerate(names): for letter in name: name_score += ord(letter) - 64 total_score += (i + 1) * name_score name_score = 0 return total_score if __name__ == "__main__": print(solution())
--- +++ @@ -1,8 +1,29 @@+""" +Name scores +Problem 22 + +Using names.txt (right click and 'Save Link/Target As...'), a 46K text file +containing over five-thousand first names, begin by sorting it into +alphabetical order. Then working out the alphabetical value for each name, +multiply this value by its alphabetical position in the list to obtain a name +score. + +For example, when the list is sorted into alphabetical order, COLIN, which is +worth 3 + 15 + 12 + 9 + 14 = 53, is the 938th name in the list. So, COLIN would +obtain a score of 938 x 53 = 49714. + +What is the total of all the name scores in the file? +""" import os def solution(): + """Returns the total of all the name scores in the file. + + >>> solution() + 871198282 + """ with open(os.path.dirname(__file__) + "/p022_names.txt") as file: names = str(file.readlines()[0]) names = names.replace('"', "").split(",") @@ -22,4 +43,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_022/sol1.py
Generate descriptive docstrings automatically
from math import factorial def solution(num: int = 100) -> int: return sum(map(int, str(factorial(num)))) if __name__ == "__main__": print(solution(int(input("Enter the Number: ").strip())))
--- +++ @@ -1,10 +1,42 @@+""" +Problem 20: https://projecteuler.net/problem=20 + +n! means n x (n - 1) x ... x 3 x 2 x 1 + +For example, 10! = 10 x 9 x ... x 3 x 2 x 1 = 3628800, +and the sum of the digits in the number 10! is 3 + 6 + 2 + 8 + 8 + 0 + 0 = 27. + +Find the sum of the digits in the number 100! +""" from math import factorial def solution(num: int = 100) -> int: + """Returns the sum of the digits in the factorial of num + >>> solution(1000) + 10539 + >>> solution(200) + 1404 + >>> solution(100) + 648 + >>> solution(50) + 216 + >>> solution(10) + 27 + >>> solution(5) + 3 + >>> solution(3) + 6 + >>> solution(2) + 2 + >>> solution(1) + 1 + >>> solution(0) + 1 + """ return sum(map(int, str(factorial(num)))) if __name__ == "__main__": - print(solution(int(input("Enter the Number: ").strip())))+ print(solution(int(input("Enter the Number: ").strip())))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_020/sol3.py
Add standardized docstrings across the file
from itertools import permutations def solution(): result = list(map("".join, permutations("0123456789"))) return result[999999] if __name__ == "__main__": print(solution())
--- +++ @@ -1,11 +1,28 @@+""" +A permutation is an ordered arrangement of objects. For example, 3124 is one +possible permutation of the digits 1, 2, 3 and 4. If all of the permutations +are listed numerically or alphabetically, we call it lexicographic order. The +lexicographic permutations of 0, 1 and 2 are: + + 012 021 102 120 201 210 + +What is the millionth lexicographic permutation of the digits 0, 1, 2, 3, 4, 5, +6, 7, 8 and 9? +""" from itertools import permutations def solution(): + """Returns the millionth lexicographic permutation of the digits 0, 1, 2, + 3, 4, 5, 6, 7, 8 and 9. + + >>> solution() + '2783915460' + """ result = list(map("".join, permutations("0123456789"))) return result[999999] if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_024/sol1.py
Add inline docstrings for readability
import os def solution(): total_sum = 0 temp_sum = 0 with open(os.path.dirname(__file__) + "/p022_names.txt") as file: name = str(file.readlines()[0]) name = name.replace('"', "").split(",") name.sort() for i in range(len(name)): for j in name[i]: temp_sum += ord(j) - ord("A") + 1 total_sum += (i + 1) * temp_sum temp_sum = 0 return total_sum if __name__ == "__main__": print(solution())
--- +++ @@ -1,8 +1,29 @@+""" +Name scores +Problem 22 + +Using names.txt (right click and 'Save Link/Target As...'), a 46K text file +containing over five-thousand first names, begin by sorting it into +alphabetical order. Then working out the alphabetical value for each name, +multiply this value by its alphabetical position in the list to obtain a name +score. + +For example, when the list is sorted into alphabetical order, COLIN, which is +worth 3 + 15 + 12 + 9 + 14 = 53, is the 938th name in the list. So, COLIN would +obtain a score of 938 x 53 = 49714. + +What is the total of all the name scores in the file? +""" import os def solution(): + """Returns the total of all the name scores in the file. + + >>> solution() + 871198282 + """ total_sum = 0 temp_sum = 0 with open(os.path.dirname(__file__) + "/p022_names.txt") as file: @@ -19,4 +40,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_022/sol2.py
Write docstrings for algorithm functions
def fibonacci(n: int) -> int: if n == 1 or not isinstance(n, int): return 0 elif n == 2: return 1 else: sequence = [0, 1] for i in range(2, n + 1): sequence.append(sequence[i - 1] + sequence[i - 2]) return sequence[n] def fibonacci_digits_index(n: int) -> int: digits = 0 index = 2 while digits < n: index += 1 digits = len(str(fibonacci(index))) return index def solution(n: int = 1000) -> int: return fibonacci_digits_index(n) if __name__ == "__main__": print(solution(int(str(input()).strip())))
--- +++ @@ -1,6 +1,48 @@+""" +The Fibonacci sequence is defined by the recurrence relation: + + Fn = Fn-1 + Fn-2, where F1 = 1 and F2 = 1. + +Hence the first 12 terms will be: + + F1 = 1 + F2 = 1 + F3 = 2 + F4 = 3 + F5 = 5 + F6 = 8 + F7 = 13 + F8 = 21 + F9 = 34 + F10 = 55 + F11 = 89 + F12 = 144 + +The 12th term, F12, is the first term to contain three digits. + +What is the index of the first term in the Fibonacci sequence to contain 1000 +digits? +""" def fibonacci(n: int) -> int: + """ + Computes the Fibonacci number for input n by iterating through n numbers + and creating an array of ints using the Fibonacci formula. + Returns the nth element of the array. + + >>> fibonacci(2) + 1 + >>> fibonacci(3) + 2 + >>> fibonacci(5) + 5 + >>> fibonacci(10) + 55 + >>> fibonacci(12) + 144 + + """ if n == 1 or not isinstance(n, int): return 0 elif n == 2: @@ -14,6 +56,20 @@ def fibonacci_digits_index(n: int) -> int: + """ + Computes incrementing Fibonacci numbers starting from 3 until the length + of the resulting Fibonacci result is the input value n. Returns the term + of the Fibonacci sequence where this occurs. + + >>> fibonacci_digits_index(1000) + 4782 + >>> fibonacci_digits_index(100) + 476 + >>> fibonacci_digits_index(50) + 237 + >>> fibonacci_digits_index(3) + 12 + """ digits = 0 index = 2 @@ -25,8 +81,21 @@ def solution(n: int = 1000) -> int: + """ + Returns the index of the first term in the Fibonacci sequence to contain + n digits. + + >>> solution(1000) + 4782 + >>> solution(100) + 476 + >>> solution(50) + 237 + >>> solution(3) + 12 + """ return fibonacci_digits_index(n) if __name__ == "__main__": - print(solution(int(str(input()).strip())))+ print(solution(int(str(input()).strip())))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_025/sol1.py
Write docstrings for algorithm functions
def solution(n: int = 1000) -> int: f1, f2 = 1, 1 index = 2 while True: i = 0 f = f1 + f2 f1, f2 = f2, f index += 1 for _ in str(f): i += 1 if i == n: break return index if __name__ == "__main__": print(solution(int(str(input()).strip())))
--- +++ @@ -1,6 +1,43 @@+""" +The Fibonacci sequence is defined by the recurrence relation: + + Fn = Fn-1 + Fn-2, where F1 = 1 and F2 = 1. + +Hence the first 12 terms will be: + + F1 = 1 + F2 = 1 + F3 = 2 + F4 = 3 + F5 = 5 + F6 = 8 + F7 = 13 + F8 = 21 + F9 = 34 + F10 = 55 + F11 = 89 + F12 = 144 + +The 12th term, F12, is the first term to contain three digits. + +What is the index of the first term in the Fibonacci sequence to contain 1000 +digits? +""" def solution(n: int = 1000) -> int: + """Returns the index of the first term in the Fibonacci sequence to contain + n digits. + + >>> solution(1000) + 4782 + >>> solution(100) + 476 + >>> solution(50) + 237 + >>> solution(3) + 12 + """ f1, f2 = 1, 1 index = 2 while True: @@ -16,4 +53,4 @@ if __name__ == "__main__": - print(solution(int(str(input()).strip())))+ print(solution(int(str(input()).strip())))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_025/sol3.py
Add docstrings to incomplete code
from collections.abc import Generator def fibonacci_generator() -> Generator[int]: a, b = 0, 1 while True: a, b = b, a + b yield b def solution(n: int = 1000) -> int: answer = 1 gen = fibonacci_generator() while len(str(next(gen))) < n: answer += 1 return answer + 1 if __name__ == "__main__": print(solution(int(str(input()).strip())))
--- +++ @@ -1,8 +1,48 @@+""" +The Fibonacci sequence is defined by the recurrence relation: + + Fn = Fn-1 + Fn-2, where F1 = 1 and F2 = 1. + +Hence the first 12 terms will be: + + F1 = 1 + F2 = 1 + F3 = 2 + F4 = 3 + F5 = 5 + F6 = 8 + F7 = 13 + F8 = 21 + F9 = 34 + F10 = 55 + F11 = 89 + F12 = 144 + +The 12th term, F12, is the first term to contain three digits. + +What is the index of the first term in the Fibonacci sequence to contain 1000 +digits? +""" from collections.abc import Generator def fibonacci_generator() -> Generator[int]: + """ + A generator that produces numbers in the Fibonacci sequence + + >>> generator = fibonacci_generator() + >>> next(generator) + 1 + >>> next(generator) + 2 + >>> next(generator) + 3 + >>> next(generator) + 5 + >>> next(generator) + 8 + """ a, b = 0, 1 while True: a, b = b, a + b @@ -10,6 +50,18 @@ def solution(n: int = 1000) -> int: + """Returns the index of the first term in the Fibonacci sequence to contain + n digits. + + >>> solution(1000) + 4782 + >>> solution(100) + 476 + >>> solution(50) + 237 + >>> solution(3) + 12 + """ answer = 1 gen = fibonacci_generator() while len(str(next(gen))) < n: @@ -18,4 +70,4 @@ if __name__ == "__main__": - print(solution(int(str(input()).strip())))+ print(solution(int(str(input()).strip())))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_025/sol2.py
Add detailed docstrings explaining each function
from math import sqrt from maths.greatest_common_divisor import gcd_by_iterative def is_prime(number: int) -> bool: # precondition assert isinstance(number, int) and (number >= 0), ( "'number' must been an int and positive" ) status = True # 0 and 1 are none primes. if number <= 1: status = False for divisor in range(2, round(sqrt(number)) + 1): # if 'number' divisible by 'divisor' then sets 'status' # of false and break up the loop. if number % divisor == 0: status = False break # precondition assert isinstance(status, bool), "'status' must been from type bool" return status # ------------------------------------------ def sieve_er(n): # precondition assert isinstance(n, int) and (n > 2), "'N' must been an int and > 2" # beginList: contains all natural numbers from 2 up to N begin_list = list(range(2, n + 1)) ans = [] # this list will be returns. # actual sieve of erathostenes for i in range(len(begin_list)): for j in range(i + 1, len(begin_list)): if (begin_list[i] != 0) and (begin_list[j] % begin_list[i] == 0): begin_list[j] = 0 # filters actual prime numbers. ans = [x for x in begin_list if x != 0] # precondition assert isinstance(ans, list), "'ans' must been from type list" return ans # -------------------------------- def get_prime_numbers(n): # precondition assert isinstance(n, int) and (n > 2), "'N' must been an int and > 2" ans = [] # iterates over all numbers between 2 up to N+1 # if a number is prime then appends to list 'ans' for number in range(2, n + 1): if is_prime(number): ans.append(number) # precondition assert isinstance(ans, list), "'ans' must been from type list" return ans # ----------------------------------------- def prime_factorization(number): # precondition assert isinstance(number, int) and number >= 0, "'number' must been an int and >= 0" ans = [] # this list will be returns of the function. # potential prime number factors. factor = 2 quotient = number if number in {0, 1}: ans.append(number) # if 'number' not prime then builds the prime factorization of 'number' elif not is_prime(number): while quotient != 1: if is_prime(factor) and (quotient % factor == 0): ans.append(factor) quotient /= factor else: factor += 1 else: ans.append(number) # precondition assert isinstance(ans, list), "'ans' must been from type list" return ans # ----------------------------------------- def greatest_prime_factor(number): # precondition assert isinstance(number, int) and (number >= 0), ( "'number' must been an int and >= 0" ) ans = 0 # prime factorization of 'number' prime_factors = prime_factorization(number) ans = max(prime_factors) # precondition assert isinstance(ans, int), "'ans' must been from type int" return ans # ---------------------------------------------- def smallest_prime_factor(number): # precondition assert isinstance(number, int) and (number >= 0), ( "'number' must been an int and >= 0" ) ans = 0 # prime factorization of 'number' prime_factors = prime_factorization(number) ans = min(prime_factors) # precondition assert isinstance(ans, int), "'ans' must been from type int" return ans # ---------------------- def is_even(number): # precondition assert isinstance(number, int), "'number' must been an int" assert isinstance(number % 2 == 0, bool), "compare must been from type bool" return number % 2 == 0 # ------------------------ def is_odd(number): # precondition assert isinstance(number, int), "'number' must been an int" assert isinstance(number % 2 != 0, bool), "compare must been from type bool" return number % 2 != 0 # ------------------------ def goldbach(number): # precondition assert isinstance(number, int) and (number > 2) and is_even(number), ( "'number' must been an int, even and > 2" ) ans = [] # this list will returned # creates a list of prime numbers between 2 up to 'number' prime_numbers = get_prime_numbers(number) len_pn = len(prime_numbers) # run variable for while-loops. i = 0 j = None # exit variable. for break up the loops loop = True while i < len_pn and loop: j = i + 1 while j < len_pn and loop: if prime_numbers[i] + prime_numbers[j] == number: loop = False ans.append(prime_numbers[i]) ans.append(prime_numbers[j]) j += 1 i += 1 # precondition assert ( isinstance(ans, list) and (len(ans) == 2) and (ans[0] + ans[1] == number) and is_prime(ans[0]) and is_prime(ans[1]) ), "'ans' must contains two primes. And sum of elements must been eq 'number'" return ans # ---------------------------------------------- def kg_v(number1, number2): # precondition assert ( isinstance(number1, int) and isinstance(number2, int) and (number1 >= 1) and (number2 >= 1) ), "'number1' and 'number2' must been positive integer." ans = 1 # actual answer that will be return. # for kgV (x,1) if number1 > 1 and number2 > 1: # builds the prime factorization of 'number1' and 'number2' prime_fac_1 = prime_factorization(number1) prime_fac_2 = prime_factorization(number2) elif number1 == 1 or number2 == 1: prime_fac_1 = [] prime_fac_2 = [] ans = max(number1, number2) count1 = 0 count2 = 0 done = [] # captured numbers int both 'primeFac1' and 'primeFac2' # iterates through primeFac1 for n in prime_fac_1: if n not in done: if n in prime_fac_2: count1 = prime_fac_1.count(n) count2 = prime_fac_2.count(n) for _ in range(max(count1, count2)): ans *= n else: count1 = prime_fac_1.count(n) for _ in range(count1): ans *= n done.append(n) # iterates through primeFac2 for n in prime_fac_2: if n not in done: count2 = prime_fac_2.count(n) for _ in range(count2): ans *= n done.append(n) # precondition assert isinstance(ans, int) and (ans >= 0), ( "'ans' must been from type int and positive" ) return ans # ---------------------------------- def get_prime(n): # precondition assert isinstance(n, int) and (n >= 0), "'number' must been a positive int" index = 0 ans = 2 # this variable holds the answer while index < n: index += 1 ans += 1 # counts to the next number # if ans not prime then # runs to the next prime number. while not is_prime(ans): ans += 1 # precondition assert isinstance(ans, int) and is_prime(ans), ( "'ans' must been a prime number and from type int" ) return ans # --------------------------------------------------- def get_primes_between(p_number_1, p_number_2): # precondition assert ( is_prime(p_number_1) and is_prime(p_number_2) and (p_number_1 < p_number_2) ), "The arguments must been prime numbers and 'pNumber1' < 'pNumber2'" number = p_number_1 + 1 # jump to the next number ans = [] # this list will be returns. # if number is not prime then # fetch the next prime number. while not is_prime(number): number += 1 while number < p_number_2: ans.append(number) number += 1 # fetch the next prime number. while not is_prime(number): number += 1 # precondition assert ( isinstance(ans, list) and ans[0] != p_number_1 and ans[len(ans) - 1] != p_number_2 ), "'ans' must been a list without the arguments" # 'ans' contains not 'pNumber1' and 'pNumber2' ! return ans # ---------------------------------------------------- def get_divisors(n): # precondition assert isinstance(n, int) and (n >= 1), "'n' must been int and >= 1" ans = [] # will be returned. for divisor in range(1, n + 1): if n % divisor == 0: ans.append(divisor) # precondition assert ans[0] == 1 and ans[len(ans) - 1] == n, "Error in function getDivisiors(...)" return ans # ---------------------------------------------------- def is_perfect_number(number): # precondition assert isinstance(number, int) and (number > 1), ( "'number' must been an int and >= 1" ) divisors = get_divisors(number) # precondition assert ( isinstance(divisors, list) and (divisors[0] == 1) and (divisors[len(divisors) - 1] == number) ), "Error in help-function getDivisiors(...)" # summed all divisors up to 'number' (exclusive), hence [:-1] return sum(divisors[:-1]) == number # ------------------------------------------------------------ def simplify_fraction(numerator, denominator): # precondition assert ( isinstance(numerator, int) and isinstance(denominator, int) and (denominator != 0) ), "The arguments must been from type int and 'denominator' != 0" # build the greatest common divisor of numerator and denominator. gcd_of_fraction = gcd_by_iterative(abs(numerator), abs(denominator)) # precondition assert ( isinstance(gcd_of_fraction, int) and (numerator % gcd_of_fraction == 0) and (denominator % gcd_of_fraction == 0) ), "Error in function gcd_by_iterative(...,...)" return (numerator // gcd_of_fraction, denominator // gcd_of_fraction) # ----------------------------------------------------------------- def factorial(n): # precondition assert isinstance(n, int) and (n >= 0), "'n' must been a int and >= 0" ans = 1 # this will be return. for factor in range(1, n + 1): ans *= factor return ans # ------------------------------------------------------------------- def fib(n: int) -> int: # precondition assert isinstance(n, int) and (n >= 0), "'n' must been an int and >= 0" tmp = 0 fib1 = 1 ans = 1 # this will be return for _ in range(n - 1): tmp = ans ans += fib1 fib1 = tmp return ans if __name__ == "__main__": import doctest doctest.testmod()
--- +++ @@ -1,3 +1,41 @@+""" +Created on Thu Oct 5 16:44:23 2017 + +@author: Christian Bender + +This Python library contains some useful functions to deal with +prime numbers and whole numbers. + +Overview: + +is_prime(number) +sieve_er(N) +get_prime_numbers(N) +prime_factorization(number) +greatest_prime_factor(number) +smallest_prime_factor(number) +get_prime(n) +get_primes_between(pNumber1, pNumber2) + +---- + +is_even(number) +is_odd(number) +kg_v(number1, number2) // least common multiple +get_divisors(number) // all divisors of 'number' inclusive 1, number +is_perfect_number(number) + +NEW-FUNCTIONS + +simplify_fraction(numerator, denominator) +factorial (n) // n! +fib (n) // calculate the n-th fibonacci term. + +----- + +goldbach(number) // Goldbach's assumption + +""" from math import sqrt @@ -5,6 +43,27 @@ def is_prime(number: int) -> bool: + """ + input: positive integer 'number' + returns true if 'number' is prime otherwise false. + + >>> is_prime(3) + True + >>> is_prime(10) + False + >>> is_prime(97) + True + >>> is_prime(9991) + False + >>> is_prime(-1) + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int and positive + >>> is_prime("test") + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int and positive + """ # precondition assert isinstance(number, int) and (number >= 0), ( @@ -34,6 +93,24 @@ def sieve_er(n): + """ + input: positive integer 'N' > 2 + returns a list of prime numbers from 2 up to N. + + This function implements the algorithm called + sieve of erathostenes. + + >>> sieve_er(8) + [2, 3, 5, 7] + >>> sieve_er(-1) + Traceback (most recent call last): + ... + AssertionError: 'N' must been an int and > 2 + >>> sieve_er("test") + Traceback (most recent call last): + ... + AssertionError: 'N' must been an int and > 2 + """ # precondition assert isinstance(n, int) and (n > 2), "'N' must been an int and > 2" @@ -62,6 +139,22 @@ def get_prime_numbers(n): + """ + input: positive integer 'N' > 2 + returns a list of prime numbers from 2 up to N (inclusive) + This function is more efficient as function 'sieveEr(...)' + + >>> get_prime_numbers(8) + [2, 3, 5, 7] + >>> get_prime_numbers(-1) + Traceback (most recent call last): + ... + AssertionError: 'N' must been an int and > 2 + >>> get_prime_numbers("test") + Traceback (most recent call last): + ... + AssertionError: 'N' must been an int and > 2 + """ # precondition assert isinstance(n, int) and (n > 2), "'N' must been an int and > 2" @@ -84,6 +177,25 @@ def prime_factorization(number): + """ + input: positive integer 'number' + returns a list of the prime number factors of 'number' + + >>> prime_factorization(0) + [0] + >>> prime_factorization(8) + [2, 2, 2] + >>> prime_factorization(287) + [7, 41] + >>> prime_factorization(-1) + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int and >= 0 + >>> prime_factorization("test") + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int and >= 0 + """ # precondition assert isinstance(number, int) and number >= 0, "'number' must been an int and >= 0" @@ -121,6 +233,25 @@ def greatest_prime_factor(number): + """ + input: positive integer 'number' >= 0 + returns the greatest prime number factor of 'number' + + >>> greatest_prime_factor(0) + 0 + >>> greatest_prime_factor(8) + 2 + >>> greatest_prime_factor(287) + 41 + >>> greatest_prime_factor(-1) + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int and >= 0 + >>> greatest_prime_factor("test") + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int and >= 0 + """ # precondition assert isinstance(number, int) and (number >= 0), ( @@ -144,6 +275,25 @@ def smallest_prime_factor(number): + """ + input: integer 'number' >= 0 + returns the smallest prime number factor of 'number' + + >>> smallest_prime_factor(0) + 0 + >>> smallest_prime_factor(8) + 2 + >>> smallest_prime_factor(287) + 7 + >>> smallest_prime_factor(-1) + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int and >= 0 + >>> smallest_prime_factor("test") + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int and >= 0 + """ # precondition assert isinstance(number, int) and (number >= 0), ( @@ -167,6 +317,23 @@ def is_even(number): + """ + input: integer 'number' + returns true if 'number' is even, otherwise false. + + >>> is_even(0) + True + >>> is_even(8) + True + >>> is_even(287) + False + >>> is_even(-1) + False + >>> is_even("test") + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int + """ # precondition assert isinstance(number, int), "'number' must been an int" @@ -179,6 +346,23 @@ def is_odd(number): + """ + input: integer 'number' + returns true if 'number' is odd, otherwise false. + + >>> is_odd(0) + False + >>> is_odd(8) + False + >>> is_odd(287) + True + >>> is_odd(-1) + True + >>> is_odd("test") + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int + """ # precondition assert isinstance(number, int), "'number' must been an int" @@ -191,6 +375,28 @@ def goldbach(number): + """ + Goldbach's assumption + input: a even positive integer 'number' > 2 + returns a list of two prime numbers whose sum is equal to 'number' + + >>> goldbach(8) + [3, 5] + >>> goldbach(824) + [3, 821] + >>> goldbach(0) + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int, even and > 2 + >>> goldbach(-1) + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int, even and > 2 + >>> goldbach("test") + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int, even and > 2 + """ # precondition assert isinstance(number, int) and (number > 2) and is_even(number), ( @@ -239,6 +445,30 @@ def kg_v(number1, number2): + """ + Least common multiple + input: two positive integer 'number1' and 'number2' + returns the least common multiple of 'number1' and 'number2' + + >>> kg_v(8,10) + 40 + >>> kg_v(824,67) + 55208 + >>> kg_v(1, 10) + 10 + >>> kg_v(0) + Traceback (most recent call last): + ... + TypeError: kg_v() missing 1 required positional argument: 'number2' + >>> kg_v(10,-1) + Traceback (most recent call last): + ... + AssertionError: 'number1' and 'number2' must been positive integer. + >>> kg_v("test","test2") + Traceback (most recent call last): + ... + AssertionError: 'number1' and 'number2' must been positive integer. + """ # precondition assert ( @@ -306,6 +536,26 @@ def get_prime(n): + """ + Gets the n-th prime number. + input: positive integer 'n' >= 0 + returns the n-th prime number, beginning at index 0 + + >>> get_prime(0) + 2 + >>> get_prime(8) + 23 + >>> get_prime(824) + 6337 + >>> get_prime(-1) + Traceback (most recent call last): + ... + AssertionError: 'number' must been a positive int + >>> get_prime("test") + Traceback (most recent call last): + ... + AssertionError: 'number' must been a positive int + """ # precondition assert isinstance(n, int) and (n >= 0), "'number' must been a positive int" @@ -335,6 +585,31 @@ def get_primes_between(p_number_1, p_number_2): + """ + input: prime numbers 'pNumber1' and 'pNumber2' + pNumber1 < pNumber2 + returns a list of all prime numbers between 'pNumber1' (exclusive) + and 'pNumber2' (exclusive) + + >>> get_primes_between(3, 67) + [5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61] + >>> get_primes_between(0) + Traceback (most recent call last): + ... + TypeError: get_primes_between() missing 1 required positional argument: 'p_number_2' + >>> get_primes_between(0, 1) + Traceback (most recent call last): + ... + AssertionError: The arguments must been prime numbers and 'pNumber1' < 'pNumber2' + >>> get_primes_between(-1, 3) + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int and positive + >>> get_primes_between("test","test") + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int and positive + """ # precondition assert ( @@ -374,6 +649,23 @@ def get_divisors(n): + """ + input: positive integer 'n' >= 1 + returns all divisors of n (inclusive 1 and 'n') + + >>> get_divisors(8) + [1, 2, 4, 8] + >>> get_divisors(824) + [1, 2, 4, 8, 103, 206, 412, 824] + >>> get_divisors(-1) + Traceback (most recent call last): + ... + AssertionError: 'n' must been int and >= 1 + >>> get_divisors("test") + Traceback (most recent call last): + ... + AssertionError: 'n' must been int and >= 1 + """ # precondition assert isinstance(n, int) and (n >= 1), "'n' must been int and >= 1" @@ -394,6 +686,23 @@ def is_perfect_number(number): + """ + input: positive integer 'number' > 1 + returns true if 'number' is a perfect number otherwise false. + + >>> is_perfect_number(28) + True + >>> is_perfect_number(824) + False + >>> is_perfect_number(-1) + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int and >= 1 + >>> is_perfect_number("test") + Traceback (most recent call last): + ... + AssertionError: 'number' must been an int and >= 1 + """ # precondition assert isinstance(number, int) and (number > 1), ( @@ -417,6 +726,20 @@ def simplify_fraction(numerator, denominator): + """ + input: two integer 'numerator' and 'denominator' + assumes: 'denominator' != 0 + returns: a tuple with simplify numerator and denominator. + + >>> simplify_fraction(10, 20) + (1, 2) + >>> simplify_fraction(10, -1) + (10, -1) + >>> simplify_fraction("test","test") + Traceback (most recent call last): + ... + AssertionError: The arguments must been from type int and 'denominator' != 0 + """ # precondition assert ( @@ -442,6 +765,23 @@ def factorial(n): + """ + input: positive integer 'n' + returns the factorial of 'n' (n!) + + >>> factorial(0) + 1 + >>> factorial(20) + 2432902008176640000 + >>> factorial(-1) + Traceback (most recent call last): + ... + AssertionError: 'n' must been a int and >= 0 + >>> factorial("test") + Traceback (most recent call last): + ... + AssertionError: 'n' must been a int and >= 0 + """ # precondition assert isinstance(n, int) and (n >= 0), "'n' must been a int and >= 0" @@ -458,6 +798,27 @@ def fib(n: int) -> int: + """ + input: positive integer 'n' + returns the n-th fibonacci term , indexing by 0 + + >>> fib(0) + 1 + >>> fib(5) + 8 + >>> fib(20) + 10946 + >>> fib(99) + 354224848179261915075 + >>> fib(-1) + Traceback (most recent call last): + ... + AssertionError: 'n' must been an int and >= 0 + >>> fib("test") + Traceback (most recent call last): + ... + AssertionError: 'n' must been an int and >= 0 + """ # precondition assert isinstance(n, int) and (n >= 0), "'n' must been an int and >= 0" @@ -477,4 +838,4 @@ if __name__ == "__main__": import doctest - doctest.testmod()+ doctest.testmod()
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/maths/primelib.py
Help me write clear docstrings
import math def is_prime(number: int) -> bool: if 1 < number < 4: # 2 and 3 are primes return True elif number < 2 or number % 2 == 0 or number % 3 == 0: # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes return False # All primes number are in format of 6k +/- 1 for i in range(5, int(math.sqrt(number) + 1), 6): if number % i == 0 or number % (i + 2) == 0: return False return True def solution(a_limit: int = 1000, b_limit: int = 1000) -> int: longest = [0, 0, 0] # length, a, b for a in range((a_limit * -1) + 1, a_limit): for b in range(2, b_limit): if is_prime(b): count = 0 n = 0 while is_prime((n**2) + (a * n) + b): count += 1 n += 1 if count > longest[0]: longest = [count, a, b] ans = longest[1] * longest[2] return ans if __name__ == "__main__": print(solution(1000, 1000))
--- +++ @@ -1,8 +1,49 @@+""" +Project Euler Problem 27 +https://projecteuler.net/problem=27 + +Problem Statement: + +Euler discovered the remarkable quadratic formula: +n2 + n + 41 +It turns out that the formula will produce 40 primes for the consecutive values +n = 0 to 39. However, when n = 40, 402 + 40 + 41 = 40(40 + 1) + 41 is divisible +by 41, and certainly when n = 41, 412 + 41 + 41 is clearly divisible by 41. +The incredible formula n2 - 79n + 1601 was discovered, which produces 80 primes +for the consecutive values n = 0 to 79. The product of the coefficients, -79 and +1601, is -126479. +Considering quadratics of the form: +n² + an + b, where |a| &lt; 1000 and |b| &lt; 1000 +where |n| is the modulus/absolute value of ne.g. |11| = 11 and |-4| = 4 +Find the product of the coefficients, a and b, for the quadratic expression that +produces the maximum number of primes for consecutive values of n, starting with +n = 0. +""" import math def is_prime(number: int) -> bool: + """Checks to see if a number is a prime in O(sqrt(n)). + A number is prime if it has exactly two factors: 1 and itself. + Returns boolean representing primality of given number num (i.e., if the + result is true, then the number is indeed prime else it is not). + + >>> is_prime(2) + True + >>> is_prime(3) + True + >>> is_prime(27) + False + >>> is_prime(2999) + True + >>> is_prime(0) + False + >>> is_prime(1) + False + >>> is_prime(-10) + False + """ if 1 < number < 4: # 2 and 3 are primes @@ -19,6 +60,18 @@ def solution(a_limit: int = 1000, b_limit: int = 1000) -> int: + """ + >>> solution(1000, 1000) + -59231 + >>> solution(200, 1000) + -59231 + >>> solution(200, 200) + -4925 + >>> solution(-1000, 1000) + 0 + >>> solution(-1000, -1000) + 0 + """ longest = [0, 0, 0] # length, a, b for a in range((a_limit * -1) + 1, a_limit): for b in range(2, b_limit): @@ -35,4 +88,4 @@ if __name__ == "__main__": - print(solution(1000, 1000))+ print(solution(1000, 1000))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_027/sol1.py
Generate docstrings for each module
def solution(numerator: int = 1, digit: int = 1000) -> int: the_digit = 1 longest_list_length = 0 for divide_by_number in range(numerator, digit + 1): has_been_divided: list[int] = [] now_divide = numerator for _ in range(1, digit + 1): if now_divide in has_been_divided: if longest_list_length < len(has_been_divided): longest_list_length = len(has_been_divided) the_digit = divide_by_number else: has_been_divided.append(now_divide) now_divide = now_divide * 10 % divide_by_number return the_digit # Tests if __name__ == "__main__": import doctest doctest.testmod()
--- +++ @@ -1,6 +1,40 @@+""" +Euler Problem 26 +https://projecteuler.net/problem=26 + +Problem Statement: + +A unit fraction contains 1 in the numerator. The decimal representation of the +unit fractions with denominators 2 to 10 are given: + +1/2 = 0.5 +1/3 = 0.(3) +1/4 = 0.25 +1/5 = 0.2 +1/6 = 0.1(6) +1/7 = 0.(142857) +1/8 = 0.125 +1/9 = 0.(1) +1/10 = 0.1 +Where 0.1(6) means 0.166666..., and has a 1-digit recurring cycle. It can be +seen that 1/7 has a 6-digit recurring cycle. + +Find the value of d < 1000 for which 1/d contains the longest recurring cycle +in its decimal fraction part. +""" def solution(numerator: int = 1, digit: int = 1000) -> int: + """ + Considering any range can be provided, + because as per the problem, the digit d < 1000 + >>> solution(1, 10) + 7 + >>> solution(10, 100) + 97 + >>> solution(10, 1000) + 983 + """ the_digit = 1 longest_list_length = 0 @@ -23,4 +57,4 @@ if __name__ == "__main__": import doctest - doctest.testmod()+ doctest.testmod()
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_026/sol1.py
Generate descriptive docstrings automatically
from collections.abc import Sequence def evaluate_poly(poly: Sequence[float], x: float) -> float: return sum(c * (x**i) for i, c in enumerate(poly)) def horner(poly: Sequence[float], x: float) -> float: result = 0.0 for coeff in reversed(poly): result = result * x + coeff return result if __name__ == "__main__": """ Example: >>> poly = (0.0, 0.0, 5.0, 9.3, 7.0) # f(x) = 7.0x^4 + 9.3x^3 + 5.0x^2 >>> x = -13.0 >>> # f(-13) = 7.0(-13)^4 + 9.3(-13)^3 + 5.0(-13)^2 = 180339.9 >>> evaluate_poly(poly, x) 180339.9 """ poly = (0.0, 0.0, 5.0, 9.3, 7.0) x = 10.0 print(evaluate_poly(poly, x)) print(horner(poly, x))
--- +++ @@ -2,10 +2,37 @@ def evaluate_poly(poly: Sequence[float], x: float) -> float: + """Evaluate a polynomial f(x) at specified point x and return the value. + + Arguments: + poly -- the coefficients of a polynomial as an iterable in order of + ascending degree + x -- the point at which to evaluate the polynomial + + >>> evaluate_poly((0.0, 0.0, 5.0, 9.3, 7.0), 10.0) + 79800.0 + """ return sum(c * (x**i) for i, c in enumerate(poly)) def horner(poly: Sequence[float], x: float) -> float: + """Evaluate a polynomial at specified point using Horner's method. + + In terms of computational complexity, Horner's method is an efficient method + of evaluating a polynomial. It avoids the use of expensive exponentiation, + and instead uses only multiplication and addition to evaluate the polynomial + in O(n), where n is the degree of the polynomial. + + https://en.wikipedia.org/wiki/Horner's_method + + Arguments: + poly -- the coefficients of a polynomial as an iterable in order of + ascending degree + x -- the point at which to evaluate the polynomial + + >>> horner((0.0, 0.0, 5.0, 9.3, 7.0), 10.0) + 79800.0 + """ result = 0.0 for coeff in reversed(poly): result = result * x + coeff @@ -24,4 +51,4 @@ poly = (0.0, 0.0, 5.0, 9.3, 7.0) x = 10.0 print(evaluate_poly(poly, x)) - print(horner(poly, x))+ print(horner(poly, x))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/maths/polynomial_evaluation.py
Add concise docstrings to each method
DIGITS_FIFTH_POWER = {str(digit): digit**5 for digit in range(10)} def digits_fifth_powers_sum(number: int) -> int: return sum(DIGITS_FIFTH_POWER[digit] for digit in str(number)) def solution() -> int: return sum( number for number in range(1000, 1000000) if number == digits_fifth_powers_sum(number) ) if __name__ == "__main__": print(solution())
--- +++ @@ -1,8 +1,34 @@+"""Problem Statement (Digit Fifth Powers): https://projecteuler.net/problem=30 + +Surprisingly there are only three numbers that can be written as the sum of fourth +powers of their digits: + +1634 = 1^4 + 6^4 + 3^4 + 4^4 +8208 = 8^4 + 2^4 + 0^4 + 8^4 +9474 = 9^4 + 4^4 + 7^4 + 4^4 +As 1 = 1^4 is not a sum it is not included. + +The sum of these numbers is 1634 + 8208 + 9474 = 19316. + +Find the sum of all the numbers that can be written as the sum of fifth powers of their +digits. + +9^5 = 59049 +59049 * 7 = 413343 (which is only 6 digit number) +So, numbers greater than 999999 are rejected +and also 59049 * 3 = 177147 (which exceeds the criteria of number being 3 digit) +So, number > 999 +and hence a number between 1000 and 1000000 +""" DIGITS_FIFTH_POWER = {str(digit): digit**5 for digit in range(10)} def digits_fifth_powers_sum(number: int) -> int: + """ + >>> digits_fifth_powers_sum(1234) + 1300 + """ return sum(DIGITS_FIFTH_POWER[digit] for digit in str(number)) @@ -15,4 +41,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_030/sol1.py
Add concise docstrings to each method
import itertools def is_combination_valid(combination): return ( int("".join(combination[0:2])) * int("".join(combination[2:5])) == int("".join(combination[5:9])) ) or ( int("".join(combination[0])) * int("".join(combination[1:5])) == int("".join(combination[5:9])) ) def solution(): return sum( { int("".join(pandigital[5:9])) for pandigital in itertools.permutations("123456789") if is_combination_valid(pandigital) } ) if __name__ == "__main__": print(solution())
--- +++ @@ -1,8 +1,33 @@+""" +We shall say that an n-digit number is pandigital if it makes use of all the +digits 1 to n exactly once; for example, the 5-digit number, 15234, is 1 through +5 pandigital. + +The product 7254 is unusual, as the identity, 39 x 186 = 7254, containing +multiplicand, multiplier, and product is 1 through 9 pandigital. + +Find the sum of all products whose multiplicand/multiplier/product identity can +be written as a 1 through 9 pandigital. + +HINT: Some products can be obtained in more than one way so be sure to only +include it once in your sum. +""" import itertools def is_combination_valid(combination): + """ + Checks if a combination (a tuple of 9 digits) + is a valid product equation. + + >>> is_combination_valid(('3', '9', '1', '8', '6', '7', '2', '5', '4')) + True + + >>> is_combination_valid(('1', '2', '3', '4', '5', '6', '7', '8', '9')) + False + + """ return ( int("".join(combination[0:2])) * int("".join(combination[2:5])) == int("".join(combination[5:9])) @@ -13,6 +38,13 @@ def solution(): + """ + Finds the sum of all products whose multiplicand/multiplier/product identity + can be written as a 1 through 9 pandigital + + >>> solution() + 45228 + """ return sum( { @@ -24,4 +56,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_032/sol32.py
Generate consistent docstrings
def one_pence() -> int: return 1 def two_pence(x: int) -> int: return 0 if x < 0 else two_pence(x - 2) + one_pence() def five_pence(x: int) -> int: return 0 if x < 0 else five_pence(x - 5) + two_pence(x) def ten_pence(x: int) -> int: return 0 if x < 0 else ten_pence(x - 10) + five_pence(x) def twenty_pence(x: int) -> int: return 0 if x < 0 else twenty_pence(x - 20) + ten_pence(x) def fifty_pence(x: int) -> int: return 0 if x < 0 else fifty_pence(x - 50) + twenty_pence(x) def one_pound(x: int) -> int: return 0 if x < 0 else one_pound(x - 100) + fifty_pence(x) def two_pound(x: int) -> int: return 0 if x < 0 else two_pound(x - 200) + one_pound(x) def solution(n: int = 200) -> int: return two_pound(n) if __name__ == "__main__": print(solution(int(input().strip())))
--- +++ @@ -1,3 +1,16 @@+""" +Coin sums +Problem 31: https://projecteuler.net/problem=31 + +In England the currency is made up of pound, f, and pence, p, and there are +eight coins in general circulation: + +1p, 2p, 5p, 10p, 20p, 50p, f1 (100p) and f2 (200p). +It is possible to make f2 in the following way: + +1xf1 + 1x50p + 2x20p + 1x5p + 1x2p + 3x1p +How many different ways can f2 be made using any number of coins? +""" def one_pence() -> int: @@ -33,8 +46,20 @@ def solution(n: int = 200) -> int: + """Returns the number of different ways can n pence be made using any number of + coins? + + >>> solution(500) + 6295434 + >>> solution(200) + 73682 + >>> solution(50) + 451 + >>> solution(10) + 11 + """ return two_pound(n) if __name__ == "__main__": - print(solution(int(input().strip())))+ print(solution(int(input().strip())))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_031/sol1.py
Document this code for team use
def solution(pence: int = 200) -> int: coins = [1, 2, 5, 10, 20, 50, 100, 200] number_of_ways = [0] * (pence + 1) number_of_ways[0] = 1 # base case: 1 way to make 0 pence for coin in coins: for i in range(coin, pence + 1, 1): number_of_ways[i] += number_of_ways[i - coin] return number_of_ways[pence] if __name__ == "__main__": assert solution(200) == 73682
--- +++ @@ -1,6 +1,50 @@+""" +Problem 31: https://projecteuler.net/problem=31 + +Coin sums + +In England the currency is made up of pound, f, and pence, p, and there are +eight coins in general circulation: + +1p, 2p, 5p, 10p, 20p, 50p, f1 (100p) and f2 (200p). +It is possible to make f2 in the following way: + +1xf1 + 1x50p + 2x20p + 1x5p + 1x2p + 3x1p +How many different ways can f2 be made using any number of coins? + +Hint: + > There are 100 pence in a pound (f1 = 100p) + > There are coins(in pence) are available: 1, 2, 5, 10, 20, 50, 100 and 200. + > how many different ways you can combine these values to create 200 pence. + +Example: + to make 6p there are 5 ways + 1,1,1,1,1,1 + 1,1,1,1,2 + 1,1,2,2 + 2,2,2 + 1,5 + to make 5p there are 4 ways + 1,1,1,1,1 + 1,1,1,2 + 1,2,2 + 5 +""" def solution(pence: int = 200) -> int: + """Returns the number of different ways to make X pence using any number of coins. + The solution is based on dynamic programming paradigm in a bottom-up fashion. + + >>> solution(500) + 6295434 + >>> solution(200) + 73682 + >>> solution(50) + 451 + >>> solution(10) + 11 + """ coins = [1, 2, 5, 10, 20, 50, 100, 200] number_of_ways = [0] * (pence + 1) number_of_ways[0] = 1 # base case: 1 way to make 0 pence @@ -12,4 +56,4 @@ if __name__ == "__main__": - assert solution(200) == 73682+ assert solution(200) == 73682
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_031/sol2.py
Generate consistent documentation across files
from math import factorial DIGIT_FACTORIAL = {str(d): factorial(d) for d in range(10)} def sum_of_digit_factorial(n: int) -> int: return sum(DIGIT_FACTORIAL[d] for d in str(n)) def solution() -> int: limit = 7 * factorial(9) + 1 return sum(i for i in range(3, limit) if sum_of_digit_factorial(i) == i) if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,17 +1,38 @@- -from math import factorial - -DIGIT_FACTORIAL = {str(d): factorial(d) for d in range(10)} - - -def sum_of_digit_factorial(n: int) -> int: - return sum(DIGIT_FACTORIAL[d] for d in str(n)) - - -def solution() -> int: - limit = 7 * factorial(9) + 1 - return sum(i for i in range(3, limit) if sum_of_digit_factorial(i) == i) - - -if __name__ == "__main__": - print(f"{solution() = }")+""" +Problem 34: https://projecteuler.net/problem=34 + +145 is a curious number, as 1! + 4! + 5! = 1 + 24 + 120 = 145. +Find the sum of all numbers which are equal to the sum of the factorial of their digits. +Note: As 1! = 1 and 2! = 2 are not sums they are not included. +""" + +from math import factorial + +DIGIT_FACTORIAL = {str(d): factorial(d) for d in range(10)} + + +def sum_of_digit_factorial(n: int) -> int: + """ + Returns the sum of the factorial of digits in n + >>> sum_of_digit_factorial(15) + 121 + >>> sum_of_digit_factorial(0) + 1 + """ + return sum(DIGIT_FACTORIAL[d] for d in str(n)) + + +def solution() -> int: + """ + Returns the sum of all numbers whose + sum of the factorials of all digits + add up to the number itself. + >>> solution() + 40730 + """ + limit = 7 * factorial(9) + 1 + return sum(i for i in range(3, limit) if sum_of_digit_factorial(i) == i) + + +if __name__ == "__main__": + print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_034/sol1.py
Generate docstrings for script automation
from __future__ import annotations sieve = [True] * 1000001 i = 2 while i * i <= 1000000: if sieve[i]: for j in range(i * i, 1000001, i): sieve[j] = False i += 1 def is_prime(n: int) -> bool: return sieve[n] def contains_an_even_digit(n: int) -> bool: return any(digit in "02468" for digit in str(n)) def find_circular_primes(limit: int = 1000000) -> list[int]: result = [2] # result already includes the number 2. for num in range(3, limit + 1, 2): if is_prime(num) and not contains_an_even_digit(num): str_num = str(num) list_nums = [int(str_num[j:] + str_num[:j]) for j in range(len(str_num))] if all(is_prime(i) for i in list_nums): result.append(num) return result def solution() -> int: return len(find_circular_primes()) if __name__ == "__main__": print(f"{len(find_circular_primes()) = }")
--- +++ @@ -1,37 +1,83 @@- -from __future__ import annotations - -sieve = [True] * 1000001 -i = 2 -while i * i <= 1000000: - if sieve[i]: - for j in range(i * i, 1000001, i): - sieve[j] = False - i += 1 - - -def is_prime(n: int) -> bool: - return sieve[n] - - -def contains_an_even_digit(n: int) -> bool: - return any(digit in "02468" for digit in str(n)) - - -def find_circular_primes(limit: int = 1000000) -> list[int]: - result = [2] # result already includes the number 2. - for num in range(3, limit + 1, 2): - if is_prime(num) and not contains_an_even_digit(num): - str_num = str(num) - list_nums = [int(str_num[j:] + str_num[:j]) for j in range(len(str_num))] - if all(is_prime(i) for i in list_nums): - result.append(num) - return result - - -def solution() -> int: - return len(find_circular_primes()) - - -if __name__ == "__main__": - print(f"{len(find_circular_primes()) = }")+""" +Project Euler Problem 35 +https://projecteuler.net/problem=35 + +Problem Statement: + +The number 197 is called a circular prime because all rotations of the digits: +197, 971, and 719, are themselves prime. +There are thirteen such primes below 100: 2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, +79, and 97. +How many circular primes are there below one million? + +To solve this problem in an efficient manner, we will first mark all the primes +below 1 million using the Sieve of Eratosthenes. Then, out of all these primes, +we will rule out the numbers which contain an even digit. After this we will +generate each circular combination of the number and check if all are prime. +""" + +from __future__ import annotations + +sieve = [True] * 1000001 +i = 2 +while i * i <= 1000000: + if sieve[i]: + for j in range(i * i, 1000001, i): + sieve[j] = False + i += 1 + + +def is_prime(n: int) -> bool: + """ + For 2 <= n <= 1000000, return True if n is prime. + >>> is_prime(87) + False + >>> is_prime(23) + True + >>> is_prime(25363) + False + """ + return sieve[n] + + +def contains_an_even_digit(n: int) -> bool: + """ + Return True if n contains an even digit. + >>> contains_an_even_digit(0) + True + >>> contains_an_even_digit(975317933) + False + >>> contains_an_even_digit(-245679) + True + """ + return any(digit in "02468" for digit in str(n)) + + +def find_circular_primes(limit: int = 1000000) -> list[int]: + """ + Return circular primes below limit. + >>> len(find_circular_primes(100)) + 13 + >>> len(find_circular_primes(1000000)) + 55 + """ + result = [2] # result already includes the number 2. + for num in range(3, limit + 1, 2): + if is_prime(num) and not contains_an_even_digit(num): + str_num = str(num) + list_nums = [int(str_num[j:] + str_num[:j]) for j in range(len(str_num))] + if all(is_prime(i) for i in list_nums): + result.append(num) + return result + + +def solution() -> int: + """ + >>> solution() + 55 + """ + return len(find_circular_primes()) + + +if __name__ == "__main__": + print(f"{len(find_circular_primes()) = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_035/sol1.py
Auto-generate documentation strings for this file
from __future__ import annotations from fractions import Fraction def is_digit_cancelling(num: int, den: int) -> bool: return ( num != den and num % 10 == den // 10 and (num // 10) / (den % 10) == num / den ) def fraction_list(digit_len: int) -> list[str]: solutions = [] den = 11 last_digit = int("1" + "0" * digit_len) for num in range(den, last_digit): while den <= 99: if ( (num != den) and (num % 10 == den // 10) and (den % 10 != 0) and is_digit_cancelling(num, den) ): solutions.append(f"{num}/{den}") den += 1 num += 1 den = 10 return solutions def solution(n: int = 2) -> int: result = 1.0 for fraction in fraction_list(n): frac = Fraction(fraction) result *= frac.denominator / frac.numerator return int(result) if __name__ == "__main__": print(solution())
--- +++ @@ -1,3 +1,19 @@+""" +Problem 33: https://projecteuler.net/problem=33 + +The fraction 49/98 is a curious fraction, as an inexperienced +mathematician in attempting to simplify it may incorrectly believe +that 49/98 = 4/8, which is correct, is obtained by cancelling the 9s. + +We shall consider fractions like, 30/50 = 3/5, to be trivial examples. + +There are exactly four non-trivial examples of this type of fraction, +less than one in value, and containing two digits in the numerator +and denominator. + +If the product of these four fractions is given in its lowest common +terms, find the value of the denominator. +""" from __future__ import annotations @@ -11,6 +27,18 @@ def fraction_list(digit_len: int) -> list[str]: + """ + >>> fraction_list(2) + ['16/64', '19/95', '26/65', '49/98'] + >>> fraction_list(3) + ['16/64', '19/95', '26/65', '49/98'] + >>> fraction_list(4) + ['16/64', '19/95', '26/65', '49/98'] + >>> fraction_list(0) + [] + >>> fraction_list(5) + ['16/64', '19/95', '26/65', '49/98'] + """ solutions = [] den = 11 last_digit = int("1" + "0" * digit_len) @@ -30,6 +58,9 @@ def solution(n: int = 2) -> int: + """ + Return the solution to the problem + """ result = 1.0 for fraction in fraction_list(n): frac = Fraction(fraction) @@ -38,4 +69,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_033/sol1.py
Add concise docstrings to each method
from __future__ import annotations import math def is_prime(number: int) -> bool: if 1 < number < 4: # 2 and 3 are primes return True elif number < 2 or number % 2 == 0 or number % 3 == 0: # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes return False # All primes number are in format of 6k +/- 1 for i in range(5, int(math.sqrt(number) + 1), 6): if number % i == 0 or number % (i + 2) == 0: return False return True def list_truncated_nums(n: int) -> list[int]: str_num = str(n) list_nums = [n] for i in range(1, len(str_num)): list_nums.append(int(str_num[i:])) list_nums.append(int(str_num[:-i])) return list_nums def validate(n: int) -> bool: return not ( len(str(n)) > 3 and (not is_prime(int(str(n)[-3:])) or not is_prime(int(str(n)[:3]))) ) def compute_truncated_primes(count: int = 11) -> list[int]: list_truncated_primes: list[int] = [] num = 13 while len(list_truncated_primes) != count: if validate(num): list_nums = list_truncated_nums(num) if all(is_prime(i) for i in list_nums): list_truncated_primes.append(num) num += 2 return list_truncated_primes def solution() -> int: return sum(compute_truncated_primes(11)) if __name__ == "__main__": print(f"{sum(compute_truncated_primes(11)) = }")
--- +++ @@ -1,56 +1,119 @@- -from __future__ import annotations - -import math - - -def is_prime(number: int) -> bool: - - if 1 < number < 4: - # 2 and 3 are primes - return True - elif number < 2 or number % 2 == 0 or number % 3 == 0: - # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes - return False - - # All primes number are in format of 6k +/- 1 - for i in range(5, int(math.sqrt(number) + 1), 6): - if number % i == 0 or number % (i + 2) == 0: - return False - return True - - -def list_truncated_nums(n: int) -> list[int]: - str_num = str(n) - list_nums = [n] - for i in range(1, len(str_num)): - list_nums.append(int(str_num[i:])) - list_nums.append(int(str_num[:-i])) - return list_nums - - -def validate(n: int) -> bool: - return not ( - len(str(n)) > 3 - and (not is_prime(int(str(n)[-3:])) or not is_prime(int(str(n)[:3]))) - ) - - -def compute_truncated_primes(count: int = 11) -> list[int]: - list_truncated_primes: list[int] = [] - num = 13 - while len(list_truncated_primes) != count: - if validate(num): - list_nums = list_truncated_nums(num) - if all(is_prime(i) for i in list_nums): - list_truncated_primes.append(num) - num += 2 - return list_truncated_primes - - -def solution() -> int: - return sum(compute_truncated_primes(11)) - - -if __name__ == "__main__": - print(f"{sum(compute_truncated_primes(11)) = }")+""" +Truncatable primes +Problem 37: https://projecteuler.net/problem=37 + +The number 3797 has an interesting property. Being prime itself, it is possible +to continuously remove digits from left to right, and remain prime at each stage: +3797, 797, 97, and 7. Similarly we can work from right to left: 3797, 379, 37, and 3. + +Find the sum of the only eleven primes that are both truncatable from left to right +and right to left. + +NOTE: 2, 3, 5, and 7 are not considered to be truncatable primes. +""" + +from __future__ import annotations + +import math + + +def is_prime(number: int) -> bool: + """Checks to see if a number is a prime in O(sqrt(n)). + + A number is prime if it has exactly two factors: 1 and itself. + + >>> is_prime(0) + False + >>> is_prime(1) + False + >>> is_prime(2) + True + >>> is_prime(3) + True + >>> is_prime(27) + False + >>> is_prime(87) + False + >>> is_prime(563) + True + >>> is_prime(2999) + True + >>> is_prime(67483) + False + """ + + if 1 < number < 4: + # 2 and 3 are primes + return True + elif number < 2 or number % 2 == 0 or number % 3 == 0: + # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes + return False + + # All primes number are in format of 6k +/- 1 + for i in range(5, int(math.sqrt(number) + 1), 6): + if number % i == 0 or number % (i + 2) == 0: + return False + return True + + +def list_truncated_nums(n: int) -> list[int]: + """ + Returns a list of all left and right truncated numbers of n + >>> list_truncated_nums(927628) + [927628, 27628, 92762, 7628, 9276, 628, 927, 28, 92, 8, 9] + >>> list_truncated_nums(467) + [467, 67, 46, 7, 4] + >>> list_truncated_nums(58) + [58, 8, 5] + """ + str_num = str(n) + list_nums = [n] + for i in range(1, len(str_num)): + list_nums.append(int(str_num[i:])) + list_nums.append(int(str_num[:-i])) + return list_nums + + +def validate(n: int) -> bool: + """ + To optimize the approach, we will rule out the numbers above 1000, + whose first or last three digits are not prime + >>> validate(74679) + False + >>> validate(235693) + False + >>> validate(3797) + True + """ + return not ( + len(str(n)) > 3 + and (not is_prime(int(str(n)[-3:])) or not is_prime(int(str(n)[:3]))) + ) + + +def compute_truncated_primes(count: int = 11) -> list[int]: + """ + Returns the list of truncated primes + >>> compute_truncated_primes(11) + [23, 37, 53, 73, 313, 317, 373, 797, 3137, 3797, 739397] + """ + list_truncated_primes: list[int] = [] + num = 13 + while len(list_truncated_primes) != count: + if validate(num): + list_nums = list_truncated_nums(num) + if all(is_prime(i) for i in list_nums): + list_truncated_primes.append(num) + num += 2 + return list_truncated_primes + + +def solution() -> int: + """ + Returns the sum of truncated primes + """ + return sum(compute_truncated_primes(11)) + + +if __name__ == "__main__": + print(f"{sum(compute_truncated_primes(11)) = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_037/sol1.py
Add docstrings that explain inputs and outputs
import mpmath # for roots of unity import numpy as np class FFT: def __init__(self, poly_a=None, poly_b=None): # Input as list self.polyA = list(poly_a or [0])[:] self.polyB = list(poly_b or [0])[:] # Remove leading zero coefficients while self.polyA[-1] == 0: self.polyA.pop() self.len_A = len(self.polyA) while self.polyB[-1] == 0: self.polyB.pop() self.len_B = len(self.polyB) # Add 0 to make lengths equal a power of 2 self.c_max_length = int( 2 ** np.ceil(np.log2(len(self.polyA) + len(self.polyB) - 1)) ) while len(self.polyA) < self.c_max_length: self.polyA.append(0) while len(self.polyB) < self.c_max_length: self.polyB.append(0) # A complex root used for the fourier transform self.root = complex(mpmath.root(x=1, n=self.c_max_length, k=1)) # The product self.product = self.__multiply() # Discrete fourier transform of A and B def __dft(self, which): dft = [[x] for x in self.polyA] if which == "A" else [[x] for x in self.polyB] # Corner case if len(dft) <= 1: return dft[0] next_ncol = self.c_max_length // 2 while next_ncol > 0: new_dft = [[] for i in range(next_ncol)] root = self.root**next_ncol # First half of next step current_root = 1 for j in range(self.c_max_length // (next_ncol * 2)): for i in range(next_ncol): new_dft[i].append(dft[i][j] + current_root * dft[i + next_ncol][j]) current_root *= root # Second half of next step current_root = 1 for j in range(self.c_max_length // (next_ncol * 2)): for i in range(next_ncol): new_dft[i].append(dft[i][j] - current_root * dft[i + next_ncol][j]) current_root *= root # Update dft = new_dft next_ncol = next_ncol // 2 return dft[0] # multiply the DFTs of A and B and find A*B def __multiply(self): dft_a = self.__dft("A") dft_b = self.__dft("B") inverce_c = [[dft_a[i] * dft_b[i] for i in range(self.c_max_length)]] del dft_a del dft_b # Corner Case if len(inverce_c[0]) <= 1: return inverce_c[0] # Inverse DFT next_ncol = 2 while next_ncol <= self.c_max_length: new_inverse_c = [[] for i in range(next_ncol)] root = self.root ** (next_ncol // 2) current_root = 1 # First half of next step for j in range(self.c_max_length // next_ncol): for i in range(next_ncol // 2): # Even positions new_inverse_c[i].append( ( inverce_c[i][j] + inverce_c[i][j + self.c_max_length // next_ncol] ) / 2 ) # Odd positions new_inverse_c[i + next_ncol // 2].append( ( inverce_c[i][j] - inverce_c[i][j + self.c_max_length // next_ncol] ) / (2 * current_root) ) current_root *= root # Update inverce_c = new_inverse_c next_ncol *= 2 # Unpack inverce_c = [ complex(round(x[0].real, 8), round(x[0].imag, 8)) for x in inverce_c ] # Remove leading 0's while inverce_c[-1] == 0: inverce_c.pop() return inverce_c # Overwrite __str__ for print(); Shows A, B and A*B def __str__(self): a = "A = " + " + ".join( f"{coef}*x^{i}" for i, coef in enumerate(self.polyA[: self.len_A]) ) b = "B = " + " + ".join( f"{coef}*x^{i}" for i, coef in enumerate(self.polyB[: self.len_B]) ) c = "A*B = " + " + ".join( f"{coef}*x^{i}" for i, coef in enumerate(self.product) ) return f"{a}\n{b}\n{c}" # Unit tests if __name__ == "__main__": import doctest doctest.testmod()
--- +++ @@ -1,134 +1,178 @@- -import mpmath # for roots of unity -import numpy as np - - -class FFT: - - def __init__(self, poly_a=None, poly_b=None): - # Input as list - self.polyA = list(poly_a or [0])[:] - self.polyB = list(poly_b or [0])[:] - - # Remove leading zero coefficients - while self.polyA[-1] == 0: - self.polyA.pop() - self.len_A = len(self.polyA) - - while self.polyB[-1] == 0: - self.polyB.pop() - self.len_B = len(self.polyB) - - # Add 0 to make lengths equal a power of 2 - self.c_max_length = int( - 2 ** np.ceil(np.log2(len(self.polyA) + len(self.polyB) - 1)) - ) - - while len(self.polyA) < self.c_max_length: - self.polyA.append(0) - while len(self.polyB) < self.c_max_length: - self.polyB.append(0) - # A complex root used for the fourier transform - self.root = complex(mpmath.root(x=1, n=self.c_max_length, k=1)) - - # The product - self.product = self.__multiply() - - # Discrete fourier transform of A and B - def __dft(self, which): - dft = [[x] for x in self.polyA] if which == "A" else [[x] for x in self.polyB] - # Corner case - if len(dft) <= 1: - return dft[0] - next_ncol = self.c_max_length // 2 - while next_ncol > 0: - new_dft = [[] for i in range(next_ncol)] - root = self.root**next_ncol - - # First half of next step - current_root = 1 - for j in range(self.c_max_length // (next_ncol * 2)): - for i in range(next_ncol): - new_dft[i].append(dft[i][j] + current_root * dft[i + next_ncol][j]) - current_root *= root - # Second half of next step - current_root = 1 - for j in range(self.c_max_length // (next_ncol * 2)): - for i in range(next_ncol): - new_dft[i].append(dft[i][j] - current_root * dft[i + next_ncol][j]) - current_root *= root - # Update - dft = new_dft - next_ncol = next_ncol // 2 - return dft[0] - - # multiply the DFTs of A and B and find A*B - def __multiply(self): - dft_a = self.__dft("A") - dft_b = self.__dft("B") - inverce_c = [[dft_a[i] * dft_b[i] for i in range(self.c_max_length)]] - del dft_a - del dft_b - - # Corner Case - if len(inverce_c[0]) <= 1: - return inverce_c[0] - # Inverse DFT - next_ncol = 2 - while next_ncol <= self.c_max_length: - new_inverse_c = [[] for i in range(next_ncol)] - root = self.root ** (next_ncol // 2) - current_root = 1 - # First half of next step - for j in range(self.c_max_length // next_ncol): - for i in range(next_ncol // 2): - # Even positions - new_inverse_c[i].append( - ( - inverce_c[i][j] - + inverce_c[i][j + self.c_max_length // next_ncol] - ) - / 2 - ) - # Odd positions - new_inverse_c[i + next_ncol // 2].append( - ( - inverce_c[i][j] - - inverce_c[i][j + self.c_max_length // next_ncol] - ) - / (2 * current_root) - ) - current_root *= root - # Update - inverce_c = new_inverse_c - next_ncol *= 2 - # Unpack - inverce_c = [ - complex(round(x[0].real, 8), round(x[0].imag, 8)) for x in inverce_c - ] - - # Remove leading 0's - while inverce_c[-1] == 0: - inverce_c.pop() - return inverce_c - - # Overwrite __str__ for print(); Shows A, B and A*B - def __str__(self): - a = "A = " + " + ".join( - f"{coef}*x^{i}" for i, coef in enumerate(self.polyA[: self.len_A]) - ) - b = "B = " + " + ".join( - f"{coef}*x^{i}" for i, coef in enumerate(self.polyB[: self.len_B]) - ) - c = "A*B = " + " + ".join( - f"{coef}*x^{i}" for i, coef in enumerate(self.product) - ) - - return f"{a}\n{b}\n{c}" - - -# Unit tests -if __name__ == "__main__": - import doctest - - doctest.testmod()+""" +Fast Polynomial Multiplication using radix-2 fast Fourier Transform. +""" + +import mpmath # for roots of unity +import numpy as np + + +class FFT: + """ + Fast Polynomial Multiplication using radix-2 fast Fourier Transform. + + Reference: + https://en.wikipedia.org/wiki/Cooley%E2%80%93Tukey_FFT_algorithm#The_radix-2_DIT_case + + For polynomials of degree m and n the algorithms has complexity + O(n*logn + m*logm) + + The main part of the algorithm is split in two parts: + 1) __DFT: We compute the discrete fourier transform (DFT) of A and B using a + bottom-up dynamic approach - + 2) __multiply: Once we obtain the DFT of A*B, we can similarly + invert it to obtain A*B + + The class FFT takes two polynomials A and B with complex coefficients as arguments; + The two polynomials should be represented as a sequence of coefficients starting + from the free term. Thus, for instance x + 2*x^3 could be represented as + [0,1,0,2] or (0,1,0,2). The constructor adds some zeros at the end so that the + polynomials have the same length which is a power of 2 at least the length of + their product. + + Example: + + Create two polynomials as sequences + >>> A = [0, 1, 0, 2] # x+2x^3 + >>> B = (2, 3, 4, 0) # 2+3x+4x^2 + + Create an FFT object with them + >>> x = FFT(A, B) + + Print product + >>> x.product # 2x + 3x^2 + 8x^3 + 6x^4 + 8x^5 + [(-0-0j), (2+0j), (3-0j), (8-0j), (6+0j), (8+0j)] + + __str__ test + >>> print(x) + A = 0*x^0 + 1*x^1 + 0*x^2 + 2*x^3 + B = 2*x^0 + 3*x^1 + 4*x^2 + A*B = (-0-0j)*x^0 + (2+0j)*x^1 + (3-0j)*x^2 + (8-0j)*x^3 + (6+0j)*x^4 + (8+0j)*x^5 + """ + + def __init__(self, poly_a=None, poly_b=None): + # Input as list + self.polyA = list(poly_a or [0])[:] + self.polyB = list(poly_b or [0])[:] + + # Remove leading zero coefficients + while self.polyA[-1] == 0: + self.polyA.pop() + self.len_A = len(self.polyA) + + while self.polyB[-1] == 0: + self.polyB.pop() + self.len_B = len(self.polyB) + + # Add 0 to make lengths equal a power of 2 + self.c_max_length = int( + 2 ** np.ceil(np.log2(len(self.polyA) + len(self.polyB) - 1)) + ) + + while len(self.polyA) < self.c_max_length: + self.polyA.append(0) + while len(self.polyB) < self.c_max_length: + self.polyB.append(0) + # A complex root used for the fourier transform + self.root = complex(mpmath.root(x=1, n=self.c_max_length, k=1)) + + # The product + self.product = self.__multiply() + + # Discrete fourier transform of A and B + def __dft(self, which): + dft = [[x] for x in self.polyA] if which == "A" else [[x] for x in self.polyB] + # Corner case + if len(dft) <= 1: + return dft[0] + next_ncol = self.c_max_length // 2 + while next_ncol > 0: + new_dft = [[] for i in range(next_ncol)] + root = self.root**next_ncol + + # First half of next step + current_root = 1 + for j in range(self.c_max_length // (next_ncol * 2)): + for i in range(next_ncol): + new_dft[i].append(dft[i][j] + current_root * dft[i + next_ncol][j]) + current_root *= root + # Second half of next step + current_root = 1 + for j in range(self.c_max_length // (next_ncol * 2)): + for i in range(next_ncol): + new_dft[i].append(dft[i][j] - current_root * dft[i + next_ncol][j]) + current_root *= root + # Update + dft = new_dft + next_ncol = next_ncol // 2 + return dft[0] + + # multiply the DFTs of A and B and find A*B + def __multiply(self): + dft_a = self.__dft("A") + dft_b = self.__dft("B") + inverce_c = [[dft_a[i] * dft_b[i] for i in range(self.c_max_length)]] + del dft_a + del dft_b + + # Corner Case + if len(inverce_c[0]) <= 1: + return inverce_c[0] + # Inverse DFT + next_ncol = 2 + while next_ncol <= self.c_max_length: + new_inverse_c = [[] for i in range(next_ncol)] + root = self.root ** (next_ncol // 2) + current_root = 1 + # First half of next step + for j in range(self.c_max_length // next_ncol): + for i in range(next_ncol // 2): + # Even positions + new_inverse_c[i].append( + ( + inverce_c[i][j] + + inverce_c[i][j + self.c_max_length // next_ncol] + ) + / 2 + ) + # Odd positions + new_inverse_c[i + next_ncol // 2].append( + ( + inverce_c[i][j] + - inverce_c[i][j + self.c_max_length // next_ncol] + ) + / (2 * current_root) + ) + current_root *= root + # Update + inverce_c = new_inverse_c + next_ncol *= 2 + # Unpack + inverce_c = [ + complex(round(x[0].real, 8), round(x[0].imag, 8)) for x in inverce_c + ] + + # Remove leading 0's + while inverce_c[-1] == 0: + inverce_c.pop() + return inverce_c + + # Overwrite __str__ for print(); Shows A, B and A*B + def __str__(self): + a = "A = " + " + ".join( + f"{coef}*x^{i}" for i, coef in enumerate(self.polyA[: self.len_A]) + ) + b = "B = " + " + ".join( + f"{coef}*x^{i}" for i, coef in enumerate(self.polyB[: self.len_B]) + ) + c = "A*B = " + " + ".join( + f"{coef}*x^{i}" for i, coef in enumerate(self.product) + ) + + return f"{a}\n{b}\n{c}" + + +# Unit tests +if __name__ == "__main__": + import doctest + + doctest.testmod()
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/maths/radix2_fft.py
Write clean docstrings for readability
from __future__ import annotations import math from itertools import permutations def is_prime(number: int) -> bool: if 1 < number < 4: # 2 and 3 are primes return True elif number < 2 or number % 2 == 0 or number % 3 == 0: # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes return False # All primes number are in format of 6k +/- 1 for i in range(5, int(math.sqrt(number) + 1), 6): if number % i == 0 or number % (i + 2) == 0: return False return True def solution(n: int = 7) -> int: pandigital_str = "".join(str(i) for i in range(1, n + 1)) perm_list = [int("".join(i)) for i in permutations(pandigital_str, n)] pandigitals = [num for num in perm_list if is_prime(num)] return max(pandigitals) if pandigitals else 0 if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,32 +1,77 @@- -from __future__ import annotations - -import math -from itertools import permutations - - -def is_prime(number: int) -> bool: - - if 1 < number < 4: - # 2 and 3 are primes - return True - elif number < 2 or number % 2 == 0 or number % 3 == 0: - # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes - return False - - # All primes number are in format of 6k +/- 1 - for i in range(5, int(math.sqrt(number) + 1), 6): - if number % i == 0 or number % (i + 2) == 0: - return False - return True - - -def solution(n: int = 7) -> int: - pandigital_str = "".join(str(i) for i in range(1, n + 1)) - perm_list = [int("".join(i)) for i in permutations(pandigital_str, n)] - pandigitals = [num for num in perm_list if is_prime(num)] - return max(pandigitals) if pandigitals else 0 - - -if __name__ == "__main__": - print(f"{solution() = }")+""" +Pandigital prime +Problem 41: https://projecteuler.net/problem=41 + +We shall say that an n-digit number is pandigital if it makes use of all the digits +1 to n exactly once. For example, 2143 is a 4-digit pandigital and is also prime. +What is the largest n-digit pandigital prime that exists? + +All pandigital numbers except for 1, 4 ,7 pandigital numbers are divisible by 3. +So we will check only 7 digit pandigital numbers to obtain the largest possible +pandigital prime. +""" + +from __future__ import annotations + +import math +from itertools import permutations + + +def is_prime(number: int) -> bool: + """Checks to see if a number is a prime in O(sqrt(n)). + + A number is prime if it has exactly two factors: 1 and itself. + + >>> is_prime(0) + False + >>> is_prime(1) + False + >>> is_prime(2) + True + >>> is_prime(3) + True + >>> is_prime(27) + False + >>> is_prime(87) + False + >>> is_prime(563) + True + >>> is_prime(2999) + True + >>> is_prime(67483) + False + """ + + if 1 < number < 4: + # 2 and 3 are primes + return True + elif number < 2 or number % 2 == 0 or number % 3 == 0: + # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes + return False + + # All primes number are in format of 6k +/- 1 + for i in range(5, int(math.sqrt(number) + 1), 6): + if number % i == 0 or number % (i + 2) == 0: + return False + return True + + +def solution(n: int = 7) -> int: + """ + Returns the maximum pandigital prime number of length n. + If there are none, then it will return 0. + >>> solution(2) + 0 + >>> solution(4) + 4231 + >>> solution(7) + 7652413 + """ + pandigital_str = "".join(str(i) for i in range(1, n + 1)) + perm_list = [int("".join(i)) for i in permutations(pandigital_str, n)] + pandigitals = [num for num in perm_list if is_prime(num)] + return max(pandigitals) if pandigitals else 0 + + +if __name__ == "__main__": + print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_041/sol1.py
Write docstrings for data processing functions
def is_geometric_series(series: list) -> bool: if not isinstance(series, list): raise ValueError("Input series is not valid, valid series - [2, 4, 8]") if len(series) == 0: raise ValueError("Input list must be a non empty list") if len(series) == 1: return True try: common_ratio = series[1] / series[0] for index in range(len(series) - 1): if series[index + 1] / series[index] != common_ratio: return False except ZeroDivisionError: return False return True def geometric_mean(series: list) -> float: if not isinstance(series, list): raise ValueError("Input series is not valid, valid series - [2, 4, 8]") if len(series) == 0: raise ValueError("Input list must be a non empty list") answer = 1 for value in series: answer *= value return pow(answer, 1 / len(series)) if __name__ == "__main__": import doctest doctest.testmod()
--- +++ @@ -1,6 +1,32 @@+""" +Geometric Mean +Reference : https://en.wikipedia.org/wiki/Geometric_mean + +Geometric series +Reference: https://en.wikipedia.org/wiki/Geometric_series +""" def is_geometric_series(series: list) -> bool: + """ + checking whether the input series is geometric series or not + >>> is_geometric_series([2, 4, 8]) + True + >>> is_geometric_series([3, 6, 12, 24]) + True + >>> is_geometric_series([1, 2, 3]) + False + >>> is_geometric_series([0, 0, 3]) + False + >>> is_geometric_series([]) + Traceback (most recent call last): + ... + ValueError: Input list must be a non empty list + >>> is_geometric_series(4) + Traceback (most recent call last): + ... + ValueError: Input series is not valid, valid series - [2, 4, 8] + """ if not isinstance(series, list): raise ValueError("Input series is not valid, valid series - [2, 4, 8]") if len(series) == 0: @@ -18,6 +44,29 @@ def geometric_mean(series: list) -> float: + """ + return the geometric mean of series + + >>> geometric_mean([2, 4, 8]) + 3.9999999999999996 + >>> geometric_mean([3, 6, 12, 24]) + 8.48528137423857 + >>> geometric_mean([4, 8, 16]) + 7.999999999999999 + >>> geometric_mean(4) + Traceback (most recent call last): + ... + ValueError: Input series is not valid, valid series - [2, 4, 8] + >>> geometric_mean([1, 2, 3]) + 1.8171205928321397 + >>> geometric_mean([0, 2, 3]) + 0.0 + >>> geometric_mean([]) + Traceback (most recent call last): + ... + ValueError: Input list must be a non empty list + + """ if not isinstance(series, list): raise ValueError("Input series is not valid, valid series - [2, 4, 8]") if len(series) == 0: @@ -31,4 +80,4 @@ if __name__ == "__main__": import doctest - doctest.testmod()+ doctest.testmod()
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/maths/series/geometric.py
Add docstrings to clarify complex logic
from __future__ import annotations def is_9_pandigital(n: int) -> bool: s = str(n) return len(s) == 9 and set(s) == set("123456789") def solution() -> int | None: for base_num in range(9999, 4999, -1): candidate = 100002 * base_num if is_9_pandigital(candidate): return candidate for base_num in range(333, 99, -1): candidate = 1002003 * base_num if is_9_pandigital(candidate): return candidate return None if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,13 +1,65 @@+""" +Project Euler Problem 38: https://projecteuler.net/problem=38 + +Take the number 192 and multiply it by each of 1, 2, and 3: + +192 x 1 = 192 +192 x 2 = 384 +192 x 3 = 576 + +By concatenating each product we get the 1 to 9 pandigital, 192384576. We will call +192384576 the concatenated product of 192 and (1,2,3) + +The same can be achieved by starting with 9 and multiplying by 1, 2, 3, 4, and 5, +giving the pandigital, 918273645, which is the concatenated product of 9 and +(1,2,3,4,5). + +What is the largest 1 to 9 pandigital 9-digit number that can be formed as the +concatenated product of an integer with (1,2, ... , n) where n > 1? + +Solution: +Since n>1, the largest candidate for the solution will be a concactenation of +a 4-digit number and its double, a 5-digit number. +Let a be the 4-digit number. +a has 4 digits => 1000 <= a < 10000 +2a has 5 digits => 10000 <= 2a < 100000 +=> 5000 <= a < 10000 + +The concatenation of a with 2a = a * 10^5 + 2a +so our candidate for a given a is 100002 * a. +We iterate through the search space 5000 <= a < 10000 in reverse order, +calculating the candidates for each a and checking if they are 1-9 pandigital. + +In case there are no 4-digit numbers that satisfy this property, we check +the 3-digit numbers with a similar formula (the example a=192 gives a lower +bound on the length of a): +a has 3 digits, etc... +=> 100 <= a < 334, candidate = a * 10^6 + 2a * 10^3 + 3a + = 1002003 * a +""" from __future__ import annotations def is_9_pandigital(n: int) -> bool: + """ + Checks whether n is a 9-digit 1 to 9 pandigital number. + >>> is_9_pandigital(12345) + False + >>> is_9_pandigital(156284973) + True + >>> is_9_pandigital(1562849733) + False + """ s = str(n) return len(s) == 9 and set(s) == set("123456789") def solution() -> int | None: + """ + Return the largest 1 to 9 pandigital 9-digital number that can be formed as the + concatenated product of an integer with (1,2,...,n) where n > 1. + """ for base_num in range(9999, 4999, -1): candidate = 100002 * base_num if is_9_pandigital(candidate): @@ -22,4 +74,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_038/sol1.py
Create documentation strings for testing functions
from __future__ import annotations def is_palindrome(n: int | str) -> bool: n = str(n) return n == n[::-1] def solution(n: int = 1000000): total = 0 for i in range(1, n): if is_palindrome(i) and is_palindrome(bin(i).split("b")[1]): total += i return total if __name__ == "__main__": print(solution(int(str(input().strip()))))
--- +++ @@ -1,13 +1,62 @@+""" +Project Euler Problem 36 +https://projecteuler.net/problem=36 + +Problem Statement: + +Double-base palindromes +Problem 36 +The decimal number, 585 = 10010010012 (binary), is palindromic in both bases. + +Find the sum of all numbers, less than one million, which are palindromic in +base 10 and base 2. + +(Please note that the palindromic number, in either base, may not include +leading zeros.) +""" from __future__ import annotations def is_palindrome(n: int | str) -> bool: + """ + Return true if the input n is a palindrome. + Otherwise return false. n can be an integer or a string. + + >>> is_palindrome(909) + True + >>> is_palindrome(908) + False + >>> is_palindrome('10101') + True + >>> is_palindrome('10111') + False + """ n = str(n) return n == n[::-1] def solution(n: int = 1000000): + """Return the sum of all numbers, less than n , which are palindromic in + base 10 and base 2. + + >>> solution(1000000) + 872187 + >>> solution(500000) + 286602 + >>> solution(100000) + 286602 + >>> solution(1000) + 1772 + >>> solution(100) + 157 + >>> solution(10) + 25 + >>> solution(2) + 1 + >>> solution(1) + 0 + """ total = 0 for i in range(1, n): @@ -17,4 +66,4 @@ if __name__ == "__main__": - print(solution(int(str(input().strip()))))+ print(solution(int(str(input().strip()))))
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_036/sol1.py
Document my Python code with docstrings
from __future__ import annotations import typing from collections import Counter def pythagorean_triple(max_perimeter: int) -> typing.Counter[int]: triplets: typing.Counter[int] = Counter() for base in range(1, max_perimeter + 1): for perpendicular in range(base, max_perimeter + 1): hypotenuse = (base * base + perpendicular * perpendicular) ** 0.5 if hypotenuse == int(hypotenuse): perimeter = int(base + perpendicular + hypotenuse) if perimeter > max_perimeter: continue triplets[perimeter] += 1 return triplets def solution(n: int = 1000) -> int: triplets = pythagorean_triple(n) return triplets.most_common(1)[0][0] if __name__ == "__main__": print(f"Perimeter {solution()} has maximum solutions")
--- +++ @@ -1,27 +1,55 @@- -from __future__ import annotations - -import typing -from collections import Counter - - -def pythagorean_triple(max_perimeter: int) -> typing.Counter[int]: - triplets: typing.Counter[int] = Counter() - for base in range(1, max_perimeter + 1): - for perpendicular in range(base, max_perimeter + 1): - hypotenuse = (base * base + perpendicular * perpendicular) ** 0.5 - if hypotenuse == int(hypotenuse): - perimeter = int(base + perpendicular + hypotenuse) - if perimeter > max_perimeter: - continue - triplets[perimeter] += 1 - return triplets - - -def solution(n: int = 1000) -> int: - triplets = pythagorean_triple(n) - return triplets.most_common(1)[0][0] - - -if __name__ == "__main__": - print(f"Perimeter {solution()} has maximum solutions")+""" +Problem 39: https://projecteuler.net/problem=39 + +If p is the perimeter of a right angle triangle with integral length sides, +{a,b,c}, there are exactly three solutions for p = 120. +{20,48,52}, {24,45,51}, {30,40,50} + +For which value of p ≤ 1000, is the number of solutions maximised? +""" + +from __future__ import annotations + +import typing +from collections import Counter + + +def pythagorean_triple(max_perimeter: int) -> typing.Counter[int]: + """ + Returns a dictionary with keys as the perimeter of a right angled triangle + and value as the number of corresponding triplets. + >>> pythagorean_triple(15) + Counter({12: 1}) + >>> pythagorean_triple(40) + Counter({12: 1, 30: 1, 24: 1, 40: 1, 36: 1}) + >>> pythagorean_triple(50) + Counter({12: 1, 30: 1, 24: 1, 40: 1, 36: 1, 48: 1}) + """ + triplets: typing.Counter[int] = Counter() + for base in range(1, max_perimeter + 1): + for perpendicular in range(base, max_perimeter + 1): + hypotenuse = (base * base + perpendicular * perpendicular) ** 0.5 + if hypotenuse == int(hypotenuse): + perimeter = int(base + perpendicular + hypotenuse) + if perimeter > max_perimeter: + continue + triplets[perimeter] += 1 + return triplets + + +def solution(n: int = 1000) -> int: + """ + Returns perimeter with maximum solutions. + >>> solution(100) + 90 + >>> solution(200) + 180 + >>> solution(1000) + 840 + """ + triplets = pythagorean_triple(n) + return triplets.most_common(1)[0][0] + + +if __name__ == "__main__": + print(f"Perimeter {solution()} has maximum solutions")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_039/sol1.py
Provide docstrings following PEP 257
def hexagonal_num(n: int) -> int: return n * (2 * n - 1) def is_pentagonal(n: int) -> bool: root = (1 + 24 * n) ** 0.5 return ((1 + root) / 6) % 1 == 0 def solution(start: int = 144) -> int: n = start num = hexagonal_num(n) while not is_pentagonal(num): n += 1 num = hexagonal_num(n) return num if __name__ == "__main__": print(f"{solution()} = ")
--- +++ @@ -1,22 +1,59 @@- - -def hexagonal_num(n: int) -> int: - return n * (2 * n - 1) - - -def is_pentagonal(n: int) -> bool: - root = (1 + 24 * n) ** 0.5 - return ((1 + root) / 6) % 1 == 0 - - -def solution(start: int = 144) -> int: - n = start - num = hexagonal_num(n) - while not is_pentagonal(num): - n += 1 - num = hexagonal_num(n) - return num - - -if __name__ == "__main__": - print(f"{solution()} = ")+""" +Problem 45: https://projecteuler.net/problem=45 + +Triangle, pentagonal, and hexagonal numbers are generated by the following formulae: +Triangle T(n) = (n * (n + 1)) / 2 1, 3, 6, 10, 15, ... +Pentagonal P(n) = (n * (3 * n - 1)) / 2 1, 5, 12, 22, 35, ... +Hexagonal H(n) = n * (2 * n - 1) 1, 6, 15, 28, 45, ... +It can be verified that T(285) = P(165) = H(143) = 40755. + +Find the next triangle number that is also pentagonal and hexagonal. +All triangle numbers are hexagonal numbers. +T(2n-1) = n * (2 * n - 1) = H(n) +So we shall check only for hexagonal numbers which are also pentagonal. +""" + + +def hexagonal_num(n: int) -> int: + """ + Returns nth hexagonal number + >>> hexagonal_num(143) + 40755 + >>> hexagonal_num(21) + 861 + >>> hexagonal_num(10) + 190 + """ + return n * (2 * n - 1) + + +def is_pentagonal(n: int) -> bool: + """ + Returns True if n is pentagonal, False otherwise. + >>> is_pentagonal(330) + True + >>> is_pentagonal(7683) + False + >>> is_pentagonal(2380) + True + """ + root = (1 + 24 * n) ** 0.5 + return ((1 + root) / 6) % 1 == 0 + + +def solution(start: int = 144) -> int: + """ + Returns the next number which is triangular, pentagonal and hexagonal. + >>> solution(144) + 1533776805 + """ + n = start + num = hexagonal_num(n) + while not is_pentagonal(num): + n += 1 + num = hexagonal_num(n) + return num + + +if __name__ == "__main__": + print(f"{solution()} = ")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_045/sol1.py
Add inline docstrings for readability
def is_pentagonal(n: int) -> bool: root = (1 + 24 * n) ** 0.5 return ((1 + root) / 6) % 1 == 0 def solution(limit: int = 5000) -> int: pentagonal_nums = [(i * (3 * i - 1)) // 2 for i in range(1, limit)] for i, pentagonal_i in enumerate(pentagonal_nums): for j in range(i, len(pentagonal_nums)): pentagonal_j = pentagonal_nums[j] a = pentagonal_i + pentagonal_j b = pentagonal_j - pentagonal_i if is_pentagonal(a) and is_pentagonal(b): return b return -1 if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,22 +1,49 @@- - -def is_pentagonal(n: int) -> bool: - root = (1 + 24 * n) ** 0.5 - return ((1 + root) / 6) % 1 == 0 - - -def solution(limit: int = 5000) -> int: - pentagonal_nums = [(i * (3 * i - 1)) // 2 for i in range(1, limit)] - for i, pentagonal_i in enumerate(pentagonal_nums): - for j in range(i, len(pentagonal_nums)): - pentagonal_j = pentagonal_nums[j] - a = pentagonal_i + pentagonal_j - b = pentagonal_j - pentagonal_i - if is_pentagonal(a) and is_pentagonal(b): - return b - - return -1 - - -if __name__ == "__main__": - print(f"{solution() = }")+""" +Problem 44: https://projecteuler.net/problem=44 + +Pentagonal numbers are generated by the formula, Pn=n(3n-1)/2. The first ten +pentagonal numbers are: +1, 5, 12, 22, 35, 51, 70, 92, 117, 145, ... +It can be seen that P4 + P7 = 22 + 70 = 92 = P8. However, their difference, +70 - 22 = 48, is not pentagonal. + +Find the pair of pentagonal numbers, Pj and Pk, for which their sum and difference +are pentagonal and D = |Pk - Pj| is minimised; what is the value of D? +""" + + +def is_pentagonal(n: int) -> bool: + """ + Returns True if n is pentagonal, False otherwise. + >>> is_pentagonal(330) + True + >>> is_pentagonal(7683) + False + >>> is_pentagonal(2380) + True + """ + root = (1 + 24 * n) ** 0.5 + return ((1 + root) / 6) % 1 == 0 + + +def solution(limit: int = 5000) -> int: + """ + Returns the minimum difference of two pentagonal numbers P1 and P2 such that + P1 + P2 is pentagonal and P2 - P1 is pentagonal. + >>> solution(5000) + 5482660 + """ + pentagonal_nums = [(i * (3 * i - 1)) // 2 for i in range(1, limit)] + for i, pentagonal_i in enumerate(pentagonal_nums): + for j in range(i, len(pentagonal_nums)): + pentagonal_j = pentagonal_nums[j] + a = pentagonal_i + pentagonal_j + b = pentagonal_j - pentagonal_i + if is_pentagonal(a) and is_pentagonal(b): + return b + + return -1 + + +if __name__ == "__main__": + print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_044/sol1.py
Auto-generate documentation strings for this file
import math from itertools import permutations def is_prime(number: int) -> bool: if 1 < number < 4: # 2 and 3 are primes return True elif number < 2 or number % 2 == 0 or number % 3 == 0: # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes return False # All primes number are in format of 6k +/- 1 for i in range(5, int(math.sqrt(number) + 1), 6): if number % i == 0 or number % (i + 2) == 0: return False return True def search(target: int, prime_list: list) -> bool: left, right = 0, len(prime_list) - 1 while left <= right: middle = (left + right) // 2 if prime_list[middle] == target: return True elif prime_list[middle] < target: left = middle + 1 else: right = middle - 1 return False def solution(): prime_list = [n for n in range(1001, 10000, 2) if is_prime(n)] candidates = [] for number in prime_list: tmp_numbers = [] for prime_member in permutations(list(str(number))): prime = int("".join(prime_member)) if prime % 2 == 0: continue if search(prime, prime_list): tmp_numbers.append(prime) tmp_numbers.sort() if len(tmp_numbers) >= 3: candidates.append(tmp_numbers) passed = [] for candidate in candidates: length = len(candidate) found = False for i in range(length): for j in range(i + 1, length): for k in range(j + 1, length): if ( abs(candidate[i] - candidate[j]) == abs(candidate[j] - candidate[k]) and len({candidate[i], candidate[j], candidate[k]}) == 3 ): passed.append( sorted([candidate[i], candidate[j], candidate[k]]) ) found = True if found: break if found: break if found: break answer = set() for seq in passed: answer.add("".join([str(i) for i in seq])) return max(int(x) for x in answer) if __name__ == "__main__": print(solution())
--- +++ @@ -1,9 +1,58 @@+""" +Prime permutations + +Problem 49 + +The arithmetic sequence, 1487, 4817, 8147, in which each of +the terms increases by 3330, is unusual in two ways: +(i) each of the three terms are prime, +(ii) each of the 4-digit numbers are permutations of one another. + +There are no arithmetic sequences made up of three 1-, 2-, or 3-digit primes, +exhibiting this property, but there is one other 4-digit increasing sequence. + +What 12-digit number do you form by concatenating the three terms in this sequence? + +Solution: + +First, we need to generate all 4 digits prime numbers. Then greedy +all of them and use permutation to form new numbers. Use binary search +to check if the permutated numbers is in our prime list and include +them in a candidate list. + +After that, bruteforce all passed candidates sequences using +3 nested loops since we know the answer will be 12 digits. +The bruteforce of this solution will be about 1 sec. +""" import math from itertools import permutations def is_prime(number: int) -> bool: + """Checks to see if a number is a prime in O(sqrt(n)). + + A number is prime if it has exactly two factors: 1 and itself. + + >>> is_prime(0) + False + >>> is_prime(1) + False + >>> is_prime(2) + True + >>> is_prime(3) + True + >>> is_prime(27) + False + >>> is_prime(87) + False + >>> is_prime(563) + True + >>> is_prime(2999) + True + >>> is_prime(67483) + False + """ if 1 < number < 4: # 2 and 3 are primes @@ -20,6 +69,15 @@ def search(target: int, prime_list: list) -> bool: + """ + function to search a number in a list using Binary Search. + >>> search(3, [1, 2, 3]) + True + >>> search(4, [1, 2, 3]) + False + >>> search(101, list(range(-100, 100))) + False + """ left, right = 0, len(prime_list) - 1 while left <= right: @@ -35,6 +93,11 @@ def solution(): + """ + Return the solution of the problem. + >>> solution() + 296962999629 + """ prime_list = [n for n in range(1001, 10000, 2) if is_prime(n)] candidates = [] @@ -87,4 +150,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_049/sol1.py
Generate missing documentation strings
from itertools import permutations def is_substring_divisible(num: tuple) -> bool: if num[3] % 2 != 0: return False if (num[2] + num[3] + num[4]) % 3 != 0: return False if num[5] % 5 != 0: return False tests = [7, 11, 13, 17] for i, test in enumerate(tests): if (num[i + 4] * 100 + num[i + 5] * 10 + num[i + 6]) % test != 0: return False return True def solution(n: int = 10) -> int: return sum( int("".join(map(str, num))) for num in permutations(range(n)) if is_substring_divisible(num) ) if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,31 +1,66 @@- -from itertools import permutations - - -def is_substring_divisible(num: tuple) -> bool: - if num[3] % 2 != 0: - return False - - if (num[2] + num[3] + num[4]) % 3 != 0: - return False - - if num[5] % 5 != 0: - return False - - tests = [7, 11, 13, 17] - for i, test in enumerate(tests): - if (num[i + 4] * 100 + num[i + 5] * 10 + num[i + 6]) % test != 0: - return False - return True - - -def solution(n: int = 10) -> int: - return sum( - int("".join(map(str, num))) - for num in permutations(range(n)) - if is_substring_divisible(num) - ) - - -if __name__ == "__main__": - print(f"{solution() = }")+""" +Problem 43: https://projecteuler.net/problem=43 + +The number, 1406357289, is a 0 to 9 pandigital number because it is made up of +each of the digits 0 to 9 in some order, but it also has a rather interesting +sub-string divisibility property. + +Let d1 be the 1st digit, d2 be the 2nd digit, and so on. In this way, we note +the following: + +d2d3d4=406 is divisible by 2 +d3d4d5=063 is divisible by 3 +d4d5d6=635 is divisible by 5 +d5d6d7=357 is divisible by 7 +d6d7d8=572 is divisible by 11 +d7d8d9=728 is divisible by 13 +d8d9d10=289 is divisible by 17 +Find the sum of all 0 to 9 pandigital numbers with this property. +""" + +from itertools import permutations + + +def is_substring_divisible(num: tuple) -> bool: + """ + Returns True if the pandigital number passes + all the divisibility tests. + >>> is_substring_divisible((0, 1, 2, 4, 6, 5, 7, 3, 8, 9)) + False + >>> is_substring_divisible((5, 1, 2, 4, 6, 0, 7, 8, 3, 9)) + False + >>> is_substring_divisible((1, 4, 0, 6, 3, 5, 7, 2, 8, 9)) + True + """ + if num[3] % 2 != 0: + return False + + if (num[2] + num[3] + num[4]) % 3 != 0: + return False + + if num[5] % 5 != 0: + return False + + tests = [7, 11, 13, 17] + for i, test in enumerate(tests): + if (num[i + 4] * 100 + num[i + 5] * 10 + num[i + 6]) % test != 0: + return False + return True + + +def solution(n: int = 10) -> int: + """ + Returns the sum of all pandigital numbers which pass the + divisibility tests. + >>> solution(10) + 16695334890 + """ + return sum( + int("".join(map(str, num))) + for num in permutations(range(n)) + if is_substring_divisible(num) + ) + + +if __name__ == "__main__": + print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_043/sol1.py
Add docstrings that explain inputs and outputs
from __future__ import annotations import math def is_prime(number: int) -> bool: if 1 < number < 4: # 2 and 3 are primes return True elif number < 2 or number % 2 == 0 or number % 3 == 0: # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes return False # All primes number are in format of 6k +/- 1 for i in range(5, int(math.sqrt(number) + 1), 6): if number % i == 0 or number % (i + 2) == 0: return False return True odd_composites = [num for num in range(3, 100001, 2) if not is_prime(num)] def compute_nums(n: int) -> list[int]: if not isinstance(n, int): raise ValueError("n must be an integer") if n <= 0: raise ValueError("n must be >= 0") list_nums = [] for num in range(len(odd_composites)): i = 0 while 2 * i * i <= odd_composites[num]: rem = odd_composites[num] - 2 * i * i if is_prime(rem): break i += 1 else: list_nums.append(odd_composites[num]) if len(list_nums) == n: return list_nums return [] def solution() -> int: return compute_nums(1)[0] if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,53 +1,116 @@- -from __future__ import annotations - -import math - - -def is_prime(number: int) -> bool: - - if 1 < number < 4: - # 2 and 3 are primes - return True - elif number < 2 or number % 2 == 0 or number % 3 == 0: - # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes - return False - - # All primes number are in format of 6k +/- 1 - for i in range(5, int(math.sqrt(number) + 1), 6): - if number % i == 0 or number % (i + 2) == 0: - return False - return True - - -odd_composites = [num for num in range(3, 100001, 2) if not is_prime(num)] - - -def compute_nums(n: int) -> list[int]: - if not isinstance(n, int): - raise ValueError("n must be an integer") - if n <= 0: - raise ValueError("n must be >= 0") - - list_nums = [] - for num in range(len(odd_composites)): - i = 0 - while 2 * i * i <= odd_composites[num]: - rem = odd_composites[num] - 2 * i * i - if is_prime(rem): - break - i += 1 - else: - list_nums.append(odd_composites[num]) - if len(list_nums) == n: - return list_nums - - return [] - - -def solution() -> int: - return compute_nums(1)[0] - - -if __name__ == "__main__": - print(f"{solution() = }")+""" +Problem 46: https://projecteuler.net/problem=46 + +It was proposed by Christian Goldbach that every odd composite number can be +written as the sum of a prime and twice a square. + +9 = 7 + 2 x 12 +15 = 7 + 2 x 22 +21 = 3 + 2 x 32 +25 = 7 + 2 x 32 +27 = 19 + 2 x 22 +33 = 31 + 2 x 12 + +It turns out that the conjecture was false. + +What is the smallest odd composite that cannot be written as the sum of a +prime and twice a square? +""" + +from __future__ import annotations + +import math + + +def is_prime(number: int) -> bool: + """Checks to see if a number is a prime in O(sqrt(n)). + + A number is prime if it has exactly two factors: 1 and itself. + + >>> is_prime(0) + False + >>> is_prime(1) + False + >>> is_prime(2) + True + >>> is_prime(3) + True + >>> is_prime(27) + False + >>> is_prime(87) + False + >>> is_prime(563) + True + >>> is_prime(2999) + True + >>> is_prime(67483) + False + """ + + if 1 < number < 4: + # 2 and 3 are primes + return True + elif number < 2 or number % 2 == 0 or number % 3 == 0: + # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes + return False + + # All primes number are in format of 6k +/- 1 + for i in range(5, int(math.sqrt(number) + 1), 6): + if number % i == 0 or number % (i + 2) == 0: + return False + return True + + +odd_composites = [num for num in range(3, 100001, 2) if not is_prime(num)] + + +def compute_nums(n: int) -> list[int]: + """ + Returns a list of first n odd composite numbers which do + not follow the conjecture. + >>> compute_nums(1) + [5777] + >>> compute_nums(2) + [5777, 5993] + >>> compute_nums(0) + Traceback (most recent call last): + ... + ValueError: n must be >= 0 + >>> compute_nums("a") + Traceback (most recent call last): + ... + ValueError: n must be an integer + >>> compute_nums(1.1) + Traceback (most recent call last): + ... + ValueError: n must be an integer + + """ + if not isinstance(n, int): + raise ValueError("n must be an integer") + if n <= 0: + raise ValueError("n must be >= 0") + + list_nums = [] + for num in range(len(odd_composites)): + i = 0 + while 2 * i * i <= odd_composites[num]: + rem = odd_composites[num] - 2 * i * i + if is_prime(rem): + break + i += 1 + else: + list_nums.append(odd_composites[num]) + if len(list_nums) == n: + return list_nums + + return [] + + +def solution() -> int: + """Return the solution to the problem""" + return compute_nums(1)[0] + + +if __name__ == "__main__": + print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_046/sol1.py
Add structured docstrings to improve clarity
from __future__ import annotations def prime_sieve(limit: int) -> list[int]: is_prime = [True] * limit is_prime[0] = False is_prime[1] = False is_prime[2] = True for i in range(3, int(limit**0.5 + 1), 2): index = i * 2 while index < limit: is_prime[index] = False index = index + i primes = [2] for i in range(3, limit, 2): if is_prime[i]: primes.append(i) return primes def solution(ceiling: int = 1_000_000) -> int: primes = prime_sieve(ceiling) length = 0 largest = 0 for i in range(len(primes)): for j in range(i + length, len(primes)): sol = sum(primes[i:j]) if sol >= ceiling: break if sol in primes: length = j - i largest = sol return largest if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,8 +1,36 @@+""" +Project Euler Problem 50: https://projecteuler.net/problem=50 + +Consecutive prime sum + +The prime 41, can be written as the sum of six consecutive primes: +41 = 2 + 3 + 5 + 7 + 11 + 13 + +This is the longest sum of consecutive primes that adds to a prime below +one-hundred. + +The longest sum of consecutive primes below one-thousand that adds to a prime, +contains 21 terms, and is equal to 953. + +Which prime, below one-million, can be written as the sum of the most +consecutive primes? +""" from __future__ import annotations def prime_sieve(limit: int) -> list[int]: + """ + Sieve of Erotosthenes + Function to return all the prime numbers up to a number 'limit' + https://en.wikipedia.org/wiki/Sieve_of_Eratosthenes + + >>> prime_sieve(3) + [2] + + >>> prime_sieve(50) + [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47] + """ is_prime = [True] * limit is_prime[0] = False is_prime[1] = False @@ -24,6 +52,19 @@ def solution(ceiling: int = 1_000_000) -> int: + """ + Returns the biggest prime, below the celing, that can be written as the sum + of consecutive the most consecutive primes. + + >>> solution(500) + 499 + + >>> solution(1_000) + 953 + + >>> solution(10_000) + 9521 + """ primes = prime_sieve(ceiling) length = 0 largest = 0 @@ -42,4 +83,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_050/sol1.py
Add detailed documentation for each class
from __future__ import annotations from collections import Counter def prime_sieve(n: int) -> list[int]: is_prime = [True] * n is_prime[0] = False is_prime[1] = False is_prime[2] = True for i in range(3, int(n**0.5 + 1), 2): index = i * 2 while index < n: is_prime[index] = False index = index + i primes = [2] for i in range(3, n, 2): if is_prime[i]: primes.append(i) return primes def digit_replacements(number: int) -> list[list[int]]: number_str = str(number) replacements = [] digits = ["0", "1", "2", "3", "4", "5", "6", "7", "8", "9"] for duplicate in Counter(number_str) - Counter(set(number_str)): family = [int(number_str.replace(duplicate, digit)) for digit in digits] replacements.append(family) return replacements def solution(family_length: int = 8) -> int: numbers_checked = set() # Filter primes with less than 3 replaceable digits primes = { x for x in set(prime_sieve(1_000_000)) if len(str(x)) - len(set(str(x))) >= 3 } for prime in primes: if prime in numbers_checked: continue replacements = digit_replacements(prime) for family in replacements: numbers_checked.update(family) primes_in_family = primes.intersection(family) if len(primes_in_family) != family_length: continue return min(primes_in_family) return -1 if __name__ == "__main__": print(solution())
--- +++ @@ -1,3 +1,20 @@+""" +https://projecteuler.net/problem=51 +Prime digit replacements +Problem 51 + +By replacing the 1st digit of the 2-digit number *3, it turns out that six of +the nine possible values: 13, 23, 43, 53, 73, and 83, are all prime. + +By replacing the 3rd and 4th digits of 56**3 with the same digit, this 5-digit +number is the first example having seven primes among the ten generated numbers, +yielding the family: 56003, 56113, 56333, 56443, 56663, 56773, and 56993. +Consequently 56003, being the first member of this family, is the smallest prime +with this property. + +Find the smallest prime which, by replacing part of the number (not necessarily +adjacent digits) with the same digit, is part of an eight prime value family. +""" from __future__ import annotations @@ -5,6 +22,17 @@ def prime_sieve(n: int) -> list[int]: + """ + Sieve of Erotosthenes + Function to return all the prime numbers up to a certain number + https://en.wikipedia.org/wiki/Sieve_of_Eratosthenes + + >>> prime_sieve(3) + [2] + + >>> prime_sieve(50) + [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47] + """ is_prime = [True] * n is_prime[0] = False is_prime[1] = False @@ -26,6 +54,16 @@ def digit_replacements(number: int) -> list[list[int]]: + """ + Returns all the possible families of digit replacements in a number which + contains at least one repeating digit + + >>> digit_replacements(544) + [[500, 511, 522, 533, 544, 555, 566, 577, 588, 599]] + + >>> digit_replacements(3112) + [[3002, 3112, 3222, 3332, 3442, 3552, 3662, 3772, 3882, 3992]] + """ number_str = str(number) replacements = [] digits = ["0", "1", "2", "3", "4", "5", "6", "7", "8", "9"] @@ -38,6 +76,15 @@ def solution(family_length: int = 8) -> int: + """ + Returns the solution of the problem + + >>> solution(2) + 229399 + + >>> solution(3) + 221311 + """ numbers_checked = set() # Filter primes with less than 3 replaceable digits @@ -64,4 +111,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_051/sol1.py
Create structured documentation for my script
from math import factorial def combinations(n, r): return factorial(n) / (factorial(r) * factorial(n - r)) def solution(): total = 0 for i in range(1, 101): for j in range(1, i + 1): if combinations(i, j) > 1e6: total += 1 return total if __name__ == "__main__": print(solution())
--- +++ @@ -1,3 +1,21 @@+""" +Combinatoric selections +Problem 53 + +There are exactly ten ways of selecting three from five, 12345: + + 123, 124, 125, 134, 135, 145, 234, 235, 245, and 345 + +In combinatorics, we use the notation, 5C3 = 10. + +In general, + +nCr = n!/(r!(n-r)!),where r ≤ n, n! = nx(n-1)x...x3x2x1, and 0! = 1. +It is not until n = 23, that a value exceeds one-million: 23C10 = 1144066. + +How many, not necessarily distinct, values of nCr, for 1 ≤ n ≤ 100, are greater +than one-million? +""" from math import factorial @@ -7,6 +25,12 @@ def solution(): + """Returns the number of values of nCr, for 1 ≤ n ≤ 100, are greater than + one-million + + >>> solution() + 4075 + """ total = 0 for i in range(1, 101): @@ -17,4 +41,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_053/sol1.py
Replace inline comments with docstrings
def is_palindrome(n: int) -> bool: return str(n) == str(n)[::-1] def sum_reverse(n: int) -> int: return int(n) + int(str(n)[::-1]) def solution(limit: int = 10000) -> int: lychrel_nums = [] for num in range(1, limit): iterations = 0 a = num while iterations < 50: num = sum_reverse(num) iterations += 1 if is_palindrome(num): break else: lychrel_nums.append(a) return len(lychrel_nums) if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,27 +1,81 @@- - -def is_palindrome(n: int) -> bool: - return str(n) == str(n)[::-1] - - -def sum_reverse(n: int) -> int: - return int(n) + int(str(n)[::-1]) - - -def solution(limit: int = 10000) -> int: - lychrel_nums = [] - for num in range(1, limit): - iterations = 0 - a = num - while iterations < 50: - num = sum_reverse(num) - iterations += 1 - if is_palindrome(num): - break - else: - lychrel_nums.append(a) - return len(lychrel_nums) - - -if __name__ == "__main__": - print(f"{solution() = }")+""" +Lychrel numbers +Problem 55: https://projecteuler.net/problem=55 + +If we take 47, reverse and add, 47 + 74 = 121, which is palindromic. + +Not all numbers produce palindromes so quickly. For example, +349 + 943 = 1292, +1292 + 2921 = 4213 +4213 + 3124 = 7337 +That is, 349 took three iterations to arrive at a palindrome. + +Although no one has proved it yet, it is thought that some numbers, like 196, +never produce a palindrome. A number that never forms a palindrome through the +reverse and add process is called a Lychrel number. Due to the theoretical nature +of these numbers, and for the purpose of this problem, we shall assume that a number +is Lychrel until proven otherwise. In addition you are given that for every number +below ten-thousand, it will either (i) become a palindrome in less than fifty +iterations, or, (ii) no one, with all the computing power that exists, has managed +so far to map it to a palindrome. In fact, 10677 is the first number to be shown +to require over fifty iterations before producing a palindrome: +4668731596684224866951378664 (53 iterations, 28-digits). + +Surprisingly, there are palindromic numbers that are themselves Lychrel numbers; +the first example is 4994. +How many Lychrel numbers are there below ten-thousand? +""" + + +def is_palindrome(n: int) -> bool: + """ + Returns True if a number is palindrome. + >>> is_palindrome(12567321) + False + >>> is_palindrome(1221) + True + >>> is_palindrome(9876789) + True + """ + return str(n) == str(n)[::-1] + + +def sum_reverse(n: int) -> int: + """ + Returns the sum of n and reverse of n. + >>> sum_reverse(123) + 444 + >>> sum_reverse(3478) + 12221 + >>> sum_reverse(12) + 33 + """ + return int(n) + int(str(n)[::-1]) + + +def solution(limit: int = 10000) -> int: + """ + Returns the count of all lychrel numbers below limit. + >>> solution(10000) + 249 + >>> solution(5000) + 76 + >>> solution(1000) + 13 + """ + lychrel_nums = [] + for num in range(1, limit): + iterations = 0 + a = num + while iterations < 50: + num = sum_reverse(num) + iterations += 1 + if is_palindrome(num): + break + else: + lychrel_nums.append(a) + return len(lychrel_nums) + + +if __name__ == "__main__": + print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_055/sol1.py
Help me add docstrings to my project
from collections import defaultdict def solution(max_base: int = 5) -> int: freqs = defaultdict(list) num = 0 while True: digits = get_digits(num) freqs[digits].append(num) if len(freqs[digits]) == max_base: base = freqs[digits][0] ** 3 return base num += 1 def get_digits(num: int) -> str: return "".join(sorted(str(num**3))) if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,8 +1,35 @@+""" +Project Euler 62 +https://projecteuler.net/problem=62 + +The cube, 41063625 (345^3), can be permuted to produce two other cubes: +56623104 (384^3) and 66430125 (405^3). In fact, 41063625 is the smallest cube +which has exactly three permutations of its digits which are also cube. + +Find the smallest cube for which exactly five permutations of its digits are +cube. +""" from collections import defaultdict def solution(max_base: int = 5) -> int: + """ + Iterate through every possible cube and sort the cube's digits in + ascending order. Sorting maintains an ordering of the digits that allows + you to compare permutations. Store each sorted sequence of digits in a + dictionary, whose key is the sequence of digits and value is a list of + numbers that are the base of the cube. + + Once you find 5 numbers that produce the same sequence of digits, return + the smallest one, which is at index 0 since we insert each base number in + ascending order. + + >>> solution(2) + 125 + >>> solution(3) + 41063625 + """ freqs = defaultdict(list) num = 0 @@ -18,8 +45,18 @@ def get_digits(num: int) -> str: + """ + Computes the sorted sequence of digits of the cube of num. + + >>> get_digits(3) + '27' + >>> get_digits(99) + '027999' + >>> get_digits(123) + '0166788' + """ return "".join(sorted(str(num**3))) if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_062/sol1.py
Document this module using docstrings
def solution(): i = 1 while True: if ( sorted(str(i)) == sorted(str(2 * i)) == sorted(str(3 * i)) == sorted(str(4 * i)) == sorted(str(5 * i)) == sorted(str(6 * i)) ): return i i += 1 if __name__ == "__main__": print(solution())
--- +++ @@ -1,6 +1,22 @@+""" +Permuted multiples +Problem 52 + +It can be seen that the number, 125874, and its double, 251748, contain exactly +the same digits, but in a different order. + +Find the smallest positive integer, x, such that 2x, 3x, 4x, 5x, and 6x, +contain the same digits. +""" def solution(): + """Returns the smallest positive integer, x, such that 2x, 3x, 4x, 5x, and + 6x, contain the same digits. + + >>> solution() + 142857 + """ i = 1 while True: @@ -18,4 +34,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_052/sol1.py
Provide docstrings following PEP 257
import math def is_prime(number: int) -> bool: if 1 < number < 4: # 2 and 3 are primes return True elif number < 2 or number % 2 == 0 or number % 3 == 0: # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes return False # All primes number are in format of 6k +/- 1 for i in range(5, int(math.sqrt(number) + 1), 6): if number % i == 0 or number % (i + 2) == 0: return False return True def solution(ratio: float = 0.1) -> int: j = 3 primes = 3 while primes / (2 * j - 1) >= ratio: for i in range(j * j + j + 1, (j + 2) * (j + 2), j + 1): primes += is_prime(i) j += 2 return j if __name__ == "__main__": import doctest doctest.testmod()
--- +++ @@ -1,8 +1,66 @@+""" +Project Euler Problem 58:https://projecteuler.net/problem=58 + + +Starting with 1 and spiralling anticlockwise in the following way, +a square spiral with side length 7 is formed. + +37 36 35 34 33 32 31 +38 17 16 15 14 13 30 +39 18 5 4 3 12 29 +40 19 6 1 2 11 28 +41 20 7 8 9 10 27 +42 21 22 23 24 25 26 +43 44 45 46 47 48 49 + +It is interesting to note that the odd squares lie along the bottom right +diagonal ,but what is more interesting is that 8 out of the 13 numbers +lying along both diagonals are prime; that is, a ratio of 8/13 ≈ 62%. + +If one complete new layer is wrapped around the spiral above, +a square spiral with side length 9 will be formed. +If this process is continued, +what is the side length of the square spiral for which +the ratio of primes along both diagonals first falls below 10%? + +Solution: We have to find an odd length side for which square falls below +10%. With every layer we add 4 elements are being added to the diagonals +,lets say we have a square spiral of odd length with side length j, +then if we move from j to j+2, we are adding j*j+j+1,j*j+2*(j+1),j*j+3*(j+1) +j*j+4*(j+1). Out of these 4 only the first three can become prime +because last one reduces to (j+2)*(j+2). +So we check individually each one of these before incrementing our +count of current primes. + +""" import math def is_prime(number: int) -> bool: + """Checks to see if a number is a prime in O(sqrt(n)). + + A number is prime if it has exactly two factors: 1 and itself. + + >>> is_prime(0) + False + >>> is_prime(1) + False + >>> is_prime(2) + True + >>> is_prime(3) + True + >>> is_prime(27) + False + >>> is_prime(87) + False + >>> is_prime(563) + True + >>> is_prime(2999) + True + >>> is_prime(67483) + False + """ if 1 < number < 4: # 2 and 3 are primes @@ -19,6 +77,17 @@ def solution(ratio: float = 0.1) -> int: + """ + Returns the side length of the square spiral of odd length greater + than 1 for which the ratio of primes along both diagonals + first falls below the given ratio. + >>> solution(.5) + 11 + >>> solution(.2) + 309 + >>> solution(.111) + 11317 + """ j = 3 primes = 3 @@ -33,4 +102,4 @@ if __name__ == "__main__": import doctest - doctest.testmod()+ doctest.testmod()
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_058/sol1.py
Replace inline comments with docstrings
def solution(): total = 0 for i in range(1, 1001): total += i**i return str(total)[-10:] if __name__ == "__main__": print(solution())
--- +++ @@ -1,6 +1,20 @@+""" +Self Powers +Problem 48 + +The series, 1^1 + 2^2 + 3^3 + ... + 10^10 = 10405071317. + +Find the last ten digits of the series, 1^1 + 2^2 + 3^3 + ... + 1000^1000. +""" def solution(): + """ + Returns the last 10 digits of the series, 1^1 + 2^2 + 3^3 + ... + 1000^1000. + + >>> solution() + '9110846700' + """ total = 0 for i in range(1, 1001): total += i**i @@ -8,4 +22,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_048/sol1.py
Add standardized docstrings across the file
def solution(n: int = 1000) -> int: prev_numerator, prev_denominator = 1, 1 result = [] for i in range(1, n + 1): numerator = prev_numerator + 2 * prev_denominator denominator = prev_numerator + prev_denominator if len(str(numerator)) > len(str(denominator)): result.append(i) prev_numerator = numerator prev_denominator = denominator return len(result) if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,36 @@+""" +Project Euler Problem 57: https://projecteuler.net/problem=57 +It is possible to show that the square root of two can be expressed as an infinite +continued fraction. + +sqrt(2) = 1 + 1 / (2 + 1 / (2 + 1 / (2 + ...))) + +By expanding this for the first four iterations, we get: +1 + 1 / 2 = 3 / 2 = 1.5 +1 + 1 / (2 + 1 / 2} = 7 / 5 = 1.4 +1 + 1 / (2 + 1 / (2 + 1 / 2)) = 17 / 12 = 1.41666... +1 + 1 / (2 + 1 / (2 + 1 / (2 + 1 / 2))) = 41/ 29 = 1.41379... + +The next three expansions are 99/70, 239/169, and 577/408, but the eighth expansion, +1393/985, is the first example where the number of digits in the numerator exceeds +the number of digits in the denominator. + +In the first one-thousand expansions, how many fractions contain a numerator with +more digits than the denominator? +""" def solution(n: int = 1000) -> int: + """ + returns number of fractions containing a numerator with more digits than + the denominator in the first n expansions. + >>> solution(14) + 2 + >>> solution(100) + 15 + >>> solution(10000) + 1508 + """ prev_numerator, prev_denominator = 1, 1 result = [] for i in range(1, n + 1): @@ -15,4 +45,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_057/sol1.py
Add concise docstrings to each method
from __future__ import annotations import os class PokerHand: _HAND_NAME = ( "High card", "One pair", "Two pairs", "Three of a kind", "Straight", "Flush", "Full house", "Four of a kind", "Straight flush", "Royal flush", ) _CARD_NAME = ( "", # placeholder as tuples are zero-indexed "One", "Two", "Three", "Four", "Five", "Six", "Seven", "Eight", "Nine", "Ten", "Jack", "Queen", "King", "Ace", ) def __init__(self, hand: str) -> None: if not isinstance(hand, str): msg = f"Hand should be of type 'str': {hand!r}" raise TypeError(msg) # split removes duplicate whitespaces so no need of strip if len(hand.split(" ")) != 5: msg = f"Hand should contain only 5 cards: {hand!r}" raise ValueError(msg) self._hand = hand self._first_pair = 0 self._second_pair = 0 self._card_values, self._card_suit = self._internal_state() self._hand_type = self._get_hand_type() self._high_card = self._card_values[0] @property def hand(self): return self._hand def compare_with(self, other: PokerHand) -> str: # Breaking the tie works on the following order of precedence: # 1. First pair (default 0) # 2. Second pair (default 0) # 3. Compare all cards in reverse order because they are sorted. # First pair and second pair will only be a non-zero value if the card # type is either from the following: # 21: Four of a kind # 20: Full house # 17: Three of a kind # 16: Two pairs # 15: One pair if self._hand_type > other._hand_type: return "Win" elif self._hand_type < other._hand_type: return "Loss" elif self._first_pair == other._first_pair: if self._second_pair == other._second_pair: return self._compare_cards(other) else: return "Win" if self._second_pair > other._second_pair else "Loss" return "Win" if self._first_pair > other._first_pair else "Loss" # This function is not part of the problem, I did it just for fun def hand_name(self) -> str: name = PokerHand._HAND_NAME[self._hand_type - 14] high = PokerHand._CARD_NAME[self._high_card] pair1 = PokerHand._CARD_NAME[self._first_pair] pair2 = PokerHand._CARD_NAME[self._second_pair] if self._hand_type in [22, 19, 18]: return name + f", {high}-high" elif self._hand_type in [21, 17, 15]: return name + f", {pair1}s" elif self._hand_type in [20, 16]: join = "over" if self._hand_type == 20 else "and" return name + f", {pair1}s {join} {pair2}s" elif self._hand_type == 23: return name else: return name + f", {high}" def _compare_cards(self, other: PokerHand) -> str: # Enumerate gives us the index as well as the element of a list for index, card_value in enumerate(self._card_values): if card_value != other._card_values[index]: return "Win" if card_value > other._card_values[index] else "Loss" return "Tie" def _get_hand_type(self) -> int: # Number representing the type of hand internally: # 23: Royal flush # 22: Straight flush # 21: Four of a kind # 20: Full house # 19: Flush # 18: Straight # 17: Three of a kind # 16: Two pairs # 15: One pair # 14: High card if self._is_flush(): if self._is_five_high_straight() or self._is_straight(): return 23 if sum(self._card_values) == 60 else 22 return 19 elif self._is_five_high_straight() or self._is_straight(): return 18 return 14 + self._is_same_kind() def _is_flush(self) -> bool: return len(self._card_suit) == 1 def _is_five_high_straight(self) -> bool: # If a card is a five high straight (low ace) change the location of # ace from the start of the list to the end. Check whether the first # element is ace or not. (Don't want to change again) # Five high straight (low ace): AH 2H 3S 4C 5D # Why use sorted here? One call to this function will mutate the list to # [5, 4, 3, 2, 14] and so for subsequent calls (which will be rare) we # need to compare the sorted version. # Refer test_multiple_calls_five_high_straight in test_poker_hand.py if sorted(self._card_values) == [2, 3, 4, 5, 14]: if self._card_values[0] == 14: # Remember, our list is sorted in reverse order ace_card = self._card_values.pop(0) self._card_values.append(ace_card) return True return False def _is_straight(self) -> bool: for i in range(4): if self._card_values[i] - self._card_values[i + 1] != 1: return False return True def _is_same_kind(self) -> int: # Kind Values for internal use: # 7: Four of a kind # 6: Full house # 3: Three of a kind # 2: Two pairs # 1: One pair # 0: False kind = val1 = val2 = 0 for i in range(4): # Compare two cards at a time, if they are same increase 'kind', # add the value of the card to val1, if it is repeating again we # will add 2 to 'kind' as there are now 3 cards with same value. # If we get card of different value than val1, we will do the same # thing with val2 if self._card_values[i] == self._card_values[i + 1]: if not val1: val1 = self._card_values[i] kind += 1 elif val1 == self._card_values[i]: kind += 2 elif not val2: val2 = self._card_values[i] kind += 1 elif val2 == self._card_values[i]: kind += 2 # For consistency in hand type (look at note in _get_hand_type function) kind = kind + 2 if kind in [4, 5] else kind # first meaning first pair to compare in 'compare_with' first = max(val1, val2) second = min(val1, val2) # If it's full house (three count pair + two count pair), make sure # first pair is three count and if not then switch them both. if kind == 6 and self._card_values.count(first) != 3: first, second = second, first self._first_pair = first self._second_pair = second return kind def _internal_state(self) -> tuple[list[int], set[str]]: # Internal representation of hand as a list of card values and # a set of card suit trans: dict = {"T": "10", "J": "11", "Q": "12", "K": "13", "A": "14"} new_hand = self._hand.translate(str.maketrans(trans)).split() card_values = [int(card[:-1]) for card in new_hand] card_suit = {card[-1] for card in new_hand} return sorted(card_values, reverse=True), card_suit def __repr__(self): return f'{self.__class__}("{self._hand}")' def __str__(self): return self._hand # Rich comparison operators (used in list.sort() and sorted() builtin functions) # Note that this is not part of the problem but another extra feature where # if you have a list of PokerHand objects, you can sort them just through # the builtin functions. def __eq__(self, other): if isinstance(other, PokerHand): return self.compare_with(other) == "Tie" return NotImplemented def __lt__(self, other): if isinstance(other, PokerHand): return self.compare_with(other) == "Loss" return NotImplemented def __le__(self, other): if isinstance(other, PokerHand): return self < other or self == other return NotImplemented def __gt__(self, other): if isinstance(other, PokerHand): return not self < other and self != other return NotImplemented def __ge__(self, other): if isinstance(other, PokerHand): return not self < other return NotImplemented def __hash__(self): return object.__hash__(self) def solution() -> int: # Solution for problem number 54 from Project Euler # Input from poker_hands.txt file answer = 0 script_dir = os.path.abspath(os.path.dirname(__file__)) poker_hands = os.path.join(script_dir, "poker_hands.txt") with open(poker_hands) as file_hand: for line in file_hand: player_hand = line[:14].strip() opponent_hand = line[15:].strip() player, opponent = PokerHand(player_hand), PokerHand(opponent_hand) output = player.compare_with(opponent) if output == "Win": answer += 1 return answer if __name__ == "__main__": solution()
--- +++ @@ -1,3 +1,45 @@+""" +Problem: https://projecteuler.net/problem=54 + +In the card game poker, a hand consists of five cards and are ranked, +from lowest to highest, in the following way: + +High Card: Highest value card. +One Pair: Two cards of the same value. +Two Pairs: Two different pairs. +Three of a Kind: Three cards of the same value. +Straight: All cards are consecutive values. +Flush: All cards of the same suit. +Full House: Three of a kind and a pair. +Four of a Kind: Four cards of the same value. +Straight Flush: All cards are consecutive values of same suit. +Royal Flush: Ten, Jack, Queen, King, Ace, in same suit. + +The cards are valued in the order: +2, 3, 4, 5, 6, 7, 8, 9, 10, Jack, Queen, King, Ace. + +If two players have the same ranked hands then the rank made up of the highest +value wins; for example, a pair of eights beats a pair of fives. +But if two ranks tie, for example, both players have a pair of queens, then highest +cards in each hand are compared; if the highest cards tie then the next highest +cards are compared, and so on. + +The file, poker.txt, contains one-thousand random hands dealt to two players. +Each line of the file contains ten cards (separated by a single space): the +first five are Player 1's cards and the last five are Player 2's cards. +You can assume that all hands are valid (no invalid characters or repeated cards), +each player's hand is in no specific order, and in each hand there is a clear winner. + +How many hands does Player 1 win? + +Resources used: +https://en.wikipedia.org/wiki/Texas_hold_%27em +https://en.wikipedia.org/wiki/List_of_poker_hands + +Similar problem on codewars: +https://www.codewars.com/kata/ranking-poker-hands +https://www.codewars.com/kata/sortable-poker-hands +""" from __future__ import annotations @@ -5,6 +47,29 @@ class PokerHand: + """Create an object representing a Poker Hand based on an input of a + string which represents the best 5-card combination from the player's hand + and board cards. + + Attributes: (read-only) + hand: a string representing the hand consisting of five cards + + Methods: + compare_with(opponent): takes in player's hand (self) and + opponent's hand (opponent) and compares both hands according to + the rules of Texas Hold'em. + Returns one of 3 strings (Win, Loss, Tie) based on whether + player's hand is better than the opponent's hand. + + hand_name(): Returns a string made up of two parts: hand name + and high card. + + Supported operators: + Rich comparison operators: <, >, <=, >=, ==, != + + Supported built-in methods and functions: + list.sort(), sorted() + """ _HAND_NAME = ( "High card", @@ -38,6 +103,22 @@ ) def __init__(self, hand: str) -> None: + """ + Initialize hand. + Hand should of type str and should contain only five cards each + separated by a space. + + The cards should be of the following format: + [card value][card suit] + + The first character is the value of the card: + 2, 3, 4, 5, 6, 7, 8, 9, T(en), J(ack), Q(ueen), K(ing), A(ce) + + The second character represents the suit: + S(pades), H(earts), D(iamonds), C(lubs) + + For example: "6S 4C KC AS TH" + """ if not isinstance(hand, str): msg = f"Hand should be of type 'str': {hand!r}" raise TypeError(msg) @@ -54,9 +135,31 @@ @property def hand(self): + """Returns the self hand""" return self._hand def compare_with(self, other: PokerHand) -> str: + """ + Determines the outcome of comparing self hand with other hand. + Returns the output as 'Win', 'Loss', 'Tie' according to the rules of + Texas Hold'em. + + Here are some examples: + >>> player = PokerHand("2H 3H 4H 5H 6H") # Stright flush + >>> opponent = PokerHand("KS AS TS QS JS") # Royal flush + >>> player.compare_with(opponent) + 'Loss' + + >>> player = PokerHand("2S AH 2H AS AC") # Full house + >>> opponent = PokerHand("2H 3H 5H 6H 7H") # Flush + >>> player.compare_with(opponent) + 'Win' + + >>> player = PokerHand("2S AH 4H 5S 6C") # High card + >>> opponent = PokerHand("AD 4C 5H 6H 2C") # High card + >>> player.compare_with(opponent) + 'Tie' + """ # Breaking the tie works on the following order of precedence: # 1. First pair (default 0) # 2. Second pair (default 0) @@ -82,6 +185,28 @@ # This function is not part of the problem, I did it just for fun def hand_name(self) -> str: + """ + Return the name of the hand in the following format: + 'hand name, high card' + + Here are some examples: + >>> PokerHand("KS AS TS QS JS").hand_name() + 'Royal flush' + + >>> PokerHand("2D 6D 3D 4D 5D").hand_name() + 'Straight flush, Six-high' + + >>> PokerHand("JC 6H JS JD JH").hand_name() + 'Four of a kind, Jacks' + + >>> PokerHand("3D 2H 3H 2C 2D").hand_name() + 'Full house, Twos over Threes' + + >>> PokerHand("2H 4D 3C AS 5S").hand_name() # Low ace + 'Straight, Five-high' + + Source: https://en.wikipedia.org/wiki/List_of_poker_hands + """ name = PokerHand._HAND_NAME[self._hand_type - 14] high = PokerHand._CARD_NAME[self._high_card] pair1 = PokerHand._CARD_NAME[self._first_pair] @@ -256,4 +381,4 @@ if __name__ == "__main__": - solution()+ solution()
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_054/sol1.py
Add docstrings for better understanding
def solution(a: int = 100, b: int = 100) -> int: # RETURN the MAXIMUM from the list of SUMs of the list of INT converted from STR of # BASE raised to the POWER return max( sum(int(x) for x in str(base**power)) for base in range(a) for power in range(b) ) # Tests if __name__ == "__main__": import doctest doctest.testmod()
--- +++ @@ -1,6 +1,31 @@+""" +Project Euler Problem 56: https://projecteuler.net/problem=56 + +A googol (10^100) is a massive number: one followed by one-hundred zeros; +100^100 is almost unimaginably large: one followed by two-hundred zeros. +Despite their size, the sum of the digits in each number is only 1. + +Considering natural numbers of the form, ab, where a, b < 100, +what is the maximum digital sum? +""" def solution(a: int = 100, b: int = 100) -> int: + """ + Considering natural numbers of the form, a**b, where a, b < 100, + what is the maximum digital sum? + :param a: + :param b: + :return: + >>> solution(10,10) + 45 + + >>> solution(100,100) + 972 + + >>> solution(100,200) + 1872 + """ # RETURN the MAXIMUM from the list of SUMs of the list of INT converted from STR of # BASE raised to the POWER @@ -13,4 +38,4 @@ if __name__ == "__main__": import doctest - doctest.testmod()+ doctest.testmod()
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_056/sol1.py
Create docstrings for reusable components
from __future__ import annotations import string from itertools import cycle, product from pathlib import Path VALID_CHARS: str = ( string.ascii_letters + string.digits + string.punctuation + string.whitespace ) LOWERCASE_INTS: list[int] = [ord(letter) for letter in string.ascii_lowercase] VALID_INTS: set[int] = {ord(char) for char in VALID_CHARS} COMMON_WORDS: list[str] = ["the", "be", "to", "of", "and", "in", "that", "have"] def try_key(ciphertext: list[int], key: tuple[int, ...]) -> str | None: decoded: str = "" keychar: int cipherchar: int decodedchar: int for keychar, cipherchar in zip(cycle(key), ciphertext): decodedchar = cipherchar ^ keychar if decodedchar not in VALID_INTS: return None decoded += chr(decodedchar) return decoded def filter_valid_chars(ciphertext: list[int]) -> list[str]: possibles: list[str] = [] for key in product(LOWERCASE_INTS, repeat=3): encoded = try_key(ciphertext, key) if encoded is not None: possibles.append(encoded) return possibles def filter_common_word(possibles: list[str], common_word: str) -> list[str]: return [possible for possible in possibles if common_word in possible.lower()] def solution(filename: str = "p059_cipher.txt") -> int: ciphertext: list[int] possibles: list[str] common_word: str decoded_text: str data: str = Path(__file__).parent.joinpath(filename).read_text(encoding="utf-8") ciphertext = [int(number) for number in data.strip().split(",")] possibles = filter_valid_chars(ciphertext) for common_word in COMMON_WORDS: possibles = filter_common_word(possibles, common_word) if len(possibles) == 1: break decoded_text = possibles[0] return sum(ord(char) for char in decoded_text) if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,3 +1,30 @@+""" +Each character on a computer is assigned a unique code and the preferred standard is +ASCII (American Standard Code for Information Interchange). +For example, uppercase A = 65, asterisk (*) = 42, and lowercase k = 107. + +A modern encryption method is to take a text file, convert the bytes to ASCII, then +XOR each byte with a given value, taken from a secret key. The advantage with the +XOR function is that using the same encryption key on the cipher text, restores +the plain text; for example, 65 XOR 42 = 107, then 107 XOR 42 = 65. + +For unbreakable encryption, the key is the same length as the plain text message, and +the key is made up of random bytes. The user would keep the encrypted message and the +encryption key in different locations, and without both "halves", it is impossible to +decrypt the message. + +Unfortunately, this method is impractical for most users, so the modified method is +to use a password as a key. If the password is shorter than the message, which is +likely, the key is repeated cyclically throughout the message. The balance for this +method is using a sufficiently long password key for security, but short enough to +be memorable. + +Your task has been made easy, as the encryption key consists of three lower case +characters. Using p059_cipher.txt (right click and 'Save Link/Target As...'), a +file containing the encrypted ASCII codes, and the knowledge that the plain text +must contain common English words, decrypt the message and find the sum of the ASCII +values in the original text. +""" from __future__ import annotations @@ -15,6 +42,16 @@ def try_key(ciphertext: list[int], key: tuple[int, ...]) -> str | None: + """ + Given an encrypted message and a possible 3-character key, decrypt the message. + If the decrypted message contains a invalid character, i.e. not an ASCII letter, + a digit, punctuation or whitespace, then we know the key is incorrect, so return + None. + >>> try_key([0, 17, 20, 4, 27], (104, 116, 120)) + 'hello' + >>> try_key([68, 10, 300, 4, 27], (104, 116, 120)) is None + True + """ decoded: str = "" keychar: int cipherchar: int @@ -30,6 +67,16 @@ def filter_valid_chars(ciphertext: list[int]) -> list[str]: + """ + Given an encrypted message, test all 3-character strings to try and find the + key. Return a list of the possible decrypted messages. + >>> from itertools import cycle + >>> text = "The enemy's gate is down" + >>> key = "end" + >>> encoded = [ord(k) ^ ord(c) for k,c in zip(cycle(key), text)] + >>> text in filter_valid_chars(encoded) + True + """ possibles: list[str] = [] for key in product(LOWERCASE_INTS, repeat=3): encoded = try_key(ciphertext, key) @@ -39,10 +86,26 @@ def filter_common_word(possibles: list[str], common_word: str) -> list[str]: + """ + Given a list of possible decoded messages, narrow down the possibilities + for checking for the presence of a specified common word. Only decoded messages + containing common_word will be returned. + >>> filter_common_word(['asfla adf', 'I am here', ' !?! #a'], 'am') + ['I am here'] + >>> filter_common_word(['athla amf', 'I am here', ' !?! #a'], 'am') + ['athla amf', 'I am here'] + """ return [possible for possible in possibles if common_word in possible.lower()] def solution(filename: str = "p059_cipher.txt") -> int: + """ + Test the ciphertext against all possible 3-character keys, then narrow down the + possibilities by filtering using common words until there's only one possible + decoded message. + >>> solution("test_cipher.txt") + 3000 + """ ciphertext: list[int] possibles: list[str] common_word: str @@ -62,4 +125,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_059/sol1.py
Create docstrings for reusable components
from functools import lru_cache def unique_prime_factors(n: int) -> set: i = 2 factors = set() while i * i <= n: if n % i: i += 1 else: n //= i factors.add(i) if n > 1: factors.add(n) return factors @lru_cache def upf_len(num: int) -> int: return len(unique_prime_factors(num)) def equality(iterable: list) -> bool: return len(set(iterable)) in (0, 1) def run(n: int) -> list[int]: # Incrementor variable for our group list comprehension. # This is the first number in each list of values # to test. base = 2 while True: # Increment each value of a generated range group = [base + i for i in range(n)] # Run elements through the unique_prime_factors function # Append our target number to the end. checker = [upf_len(x) for x in group] checker.append(n) # If all numbers in the list are equal, return the group variable. if equality(checker): return group # Increment our base variable by 1 base += 1 def solution(n: int = 4) -> int | None: results = run(n) return results[0] if len(results) else None if __name__ == "__main__": print(solution())
--- +++ @@ -1,8 +1,38 @@+""" +Combinatoric selections + +Problem 47 + +The first two consecutive numbers to have two distinct prime factors are: + +14 = 2 x 7 +15 = 3 x 5 + +The first three consecutive numbers to have three distinct prime factors are: + +644 = 2² x 7 x 23 +645 = 3 x 5 x 43 +646 = 2 x 17 x 19. + +Find the first four consecutive integers to have four distinct prime factors each. +What is the first of these numbers? +""" from functools import lru_cache def unique_prime_factors(n: int) -> set: + """ + Find unique prime factors of an integer. + Tests include sorting because only the set matters, + not the order in which it is produced. + >>> sorted(set(unique_prime_factors(14))) + [2, 7] + >>> sorted(set(unique_prime_factors(644))) + [2, 7, 23] + >>> sorted(set(unique_prime_factors(646))) + [2, 17, 19] + """ i = 2 factors = set() while i * i <= n: @@ -18,14 +48,33 @@ @lru_cache def upf_len(num: int) -> int: + """ + Memoize upf() length results for a given value. + >>> upf_len(14) + 2 + """ return len(unique_prime_factors(num)) def equality(iterable: list) -> bool: + """ + Check the equality of ALL elements in an iterable + >>> equality([1, 2, 3, 4]) + False + >>> equality([2, 2, 2, 2]) + True + >>> equality([1, 2, 3, 2, 1]) + False + """ return len(set(iterable)) in (0, 1) def run(n: int) -> list[int]: + """ + Runs core process to find problem solution. + >>> run(3) + [644, 645, 646] + """ # Incrementor variable for our group list comprehension. # This is the first number in each list of values @@ -50,9 +99,14 @@ def solution(n: int = 4) -> int | None: + """Return the first value of the first four consecutive integers to have four + distinct prime factors each. + >>> solution() + 134043 + """ results = run(n) return results[0] if len(results) else None if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_047/sol1.py
Add professional docstrings to my codebase
""" The maximum base can be 9 because all n-digit numbers < 10^n. Now 9**23 has 22 digits so the maximum power can be 22. Using these conclusions, we will calculate the result. """ def solution(max_base: int = 10, max_power: int = 22) -> int: bases = range(1, max_base) powers = range(1, max_power) return sum( 1 for power in powers for base in bases if len(str(base**power)) == power ) if __name__ == "__main__": print(f"{solution(10, 22) = }")
--- +++ @@ -1,18 +1,34 @@- -""" -The maximum base can be 9 because all n-digit numbers < 10^n. -Now 9**23 has 22 digits so the maximum power can be 22. -Using these conclusions, we will calculate the result. -""" - - -def solution(max_base: int = 10, max_power: int = 22) -> int: - bases = range(1, max_base) - powers = range(1, max_power) - return sum( - 1 for power in powers for base in bases if len(str(base**power)) == power - ) - - -if __name__ == "__main__": - print(f"{solution(10, 22) = }")+""" +The 5-digit number, 16807=75, is also a fifth power. Similarly, the 9-digit number, +134217728=89, is a ninth power. +How many n-digit positive integers exist which are also an nth power? +""" + +""" +The maximum base can be 9 because all n-digit numbers < 10^n. +Now 9**23 has 22 digits so the maximum power can be 22. +Using these conclusions, we will calculate the result. +""" + + +def solution(max_base: int = 10, max_power: int = 22) -> int: + """ + Returns the count of all n-digit numbers which are nth power + >>> solution(10, 22) + 49 + >>> solution(0, 0) + 0 + >>> solution(1, 1) + 0 + >>> solution(-1, -1) + 0 + """ + bases = range(1, max_base) + powers = range(1, max_power) + return sum( + 1 for power in powers for base in bases if len(str(base**power)) == power + ) + + +if __name__ == "__main__": + print(f"{solution(10, 22) = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_063/sol1.py
Generate docstrings for this script
import os def solution(): script_dir = os.path.dirname(os.path.realpath(__file__)) triangle = os.path.join(script_dir, "triangle.txt") with open(triangle) as f: triangle = f.readlines() a = [] for line in triangle: numbers_from_line = [] for number in line.strip().split(" "): numbers_from_line.append(int(number)) a.append(numbers_from_line) for i in range(1, len(a)): for j in range(len(a[i])): number1 = a[i - 1][j] if j != len(a[i - 1]) else 0 number2 = a[i - 1][j - 1] if j > 0 else 0 a[i][j] += max(number1, number2) return max(a[-1]) if __name__ == "__main__": print(solution())
--- +++ @@ -1,8 +1,28 @@+""" +Problem Statement: +By starting at the top of the triangle below and moving to adjacent numbers on +the row below, the maximum total from top to bottom is 23. +3 +7 4 +2 4 6 +8 5 9 3 +That is, 3 + 7 + 4 + 9 = 23. +Find the maximum total from top to bottom in triangle.txt (right click and +'Save Link/Target As...'), a 15K text file containing a triangle with +one-hundred rows. +""" import os def solution(): + """ + Finds the maximum total in a triangle as described by the problem statement + above. + + >>> solution() + 7273 + """ script_dir = os.path.dirname(os.path.realpath(__file__)) triangle = os.path.join(script_dir, "triangle.txt") @@ -25,4 +45,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_067/sol1.py
Create docstrings for reusable components
from math import floor, sqrt def continuous_fraction_period(n: int) -> int: numerator = 0.0 denominator = 1.0 root = int(sqrt(n)) integer_part = root period = 0 while integer_part != 2 * root: numerator = denominator * integer_part - numerator denominator = (n - numerator**2) / denominator integer_part = int((root + numerator) / denominator) period += 1 return period def solution(n: int = 10000) -> int: count_odd_periods = 0 for i in range(2, n + 1): sr = sqrt(i) if sr - floor(sr) != 0 and continuous_fraction_period(i) % 2 == 1: count_odd_periods += 1 return count_odd_periods if __name__ == "__main__": print(f"{solution(int(input().strip()))}")
--- +++ @@ -1,8 +1,36 @@+""" +Project Euler Problem 64: https://projecteuler.net/problem=64 + +All square roots are periodic when written as continued fractions. +For example, let us consider sqrt(23). +It can be seen that the sequence is repeating. +For conciseness, we use the notation sqrt(23)=[4;(1,3,1,8)], +to indicate that the block (1,3,1,8) repeats indefinitely. +Exactly four continued fractions, for N<=13, have an odd period. +How many continued fractions for N<=10000 have an odd period? + +References: +- https://en.wikipedia.org/wiki/Continued_fraction +""" from math import floor, sqrt def continuous_fraction_period(n: int) -> int: + """ + Returns the continued fraction period of a number n. + + >>> continuous_fraction_period(2) + 1 + >>> continuous_fraction_period(5) + 1 + >>> continuous_fraction_period(7) + 4 + >>> continuous_fraction_period(11) + 2 + >>> continuous_fraction_period(13) + 5 + """ numerator = 0.0 denominator = 1.0 root = int(sqrt(n)) @@ -17,6 +45,25 @@ def solution(n: int = 10000) -> int: + """ + Returns the count of numbers <= 10000 with odd periods. + This function calls continuous_fraction_period for numbers which are + not perfect squares. + This is checked in if sr - floor(sr) != 0 statement. + If an odd period is returned by continuous_fraction_period, + count_odd_periods is increased by 1. + + >>> solution(2) + 1 + >>> solution(5) + 2 + >>> solution(7) + 2 + >>> solution(11) + 3 + >>> solution(13) + 4 + """ count_odd_periods = 0 for i in range(2, n + 1): sr = sqrt(i) @@ -26,4 +73,4 @@ if __name__ == "__main__": - print(f"{solution(int(input().strip()))}")+ print(f"{solution(int(input().strip()))}")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_064/sol1.py
Generate documentation strings for clarity
from itertools import permutations def solution(gon_side: int = 5) -> int: if gon_side < 3 or gon_side > 5: raise ValueError("gon_side must be in the range [3, 5]") # Since it's 16, we know 10 is on the outer ring # Put the big numbers at the end so that they are never the first number small_numbers = list(range(gon_side + 1, 0, -1)) big_numbers = list(range(gon_side + 2, gon_side * 2 + 1)) for perm in permutations(small_numbers + big_numbers): numbers = generate_gon_ring(gon_side, list(perm)) if is_magic_gon(numbers): return int("".join(str(n) for n in numbers)) msg = f"Magic {gon_side}-gon ring is impossible" raise ValueError(msg) def generate_gon_ring(gon_side: int, perm: list[int]) -> list[int]: result = [0] * (gon_side * 3) result[0:3] = perm[0:3] perm.append(perm[1]) magic_number = 1 if gon_side < 5 else 2 for i in range(1, len(perm) // 3 + magic_number): result[3 * i] = perm[2 * i + 1] result[3 * i + 1] = result[3 * i - 1] result[3 * i + 2] = perm[2 * i + 2] return result def is_magic_gon(numbers: list[int]) -> bool: if len(numbers) % 3 != 0: raise ValueError("a gon ring should have a length that is a multiple of 3") if min(numbers[::3]) != numbers[0]: return False total = sum(numbers[:3]) return all(sum(numbers[i : i + 3]) == total for i in range(3, len(numbers), 3)) if __name__ == "__main__": print(solution())
--- +++ @@ -1,8 +1,65 @@+""" +Project Euler Problem 68: https://projecteuler.net/problem=68 + +Magic 5-gon ring + +Problem Statement: +Consider the following "magic" 3-gon ring, +filled with the numbers 1 to 6, and each line adding to nine. + + 4 + \ + 3 + / \ + 1 - 2 - 6 + / + 5 + +Working clockwise, and starting from the group of three +with the numerically lowest external node (4,3,2 in this example), +each solution can be described uniquely. +For example, the above solution can be described by the set: 4,3,2; 6,2,1; 5,1,3. + +It is possible to complete the ring with four different totals: 9, 10, 11, and 12. +There are eight solutions in total. +Total Solution Set +9 4,2,3; 5,3,1; 6,1,2 +9 4,3,2; 6,2,1; 5,1,3 +10 2,3,5; 4,5,1; 6,1,3 +10 2,5,3; 6,3,1; 4,1,5 +11 1,4,6; 3,6,2; 5,2,4 +11 1,6,4; 5,4,2; 3,2,6 +12 1,5,6; 2,6,4; 3,4,5 +12 1,6,5; 3,5,4; 2,4,6 + +By concatenating each group it is possible to form 9-digit strings; +the maximum string for a 3-gon ring is 432621513. + +Using the numbers 1 to 10, and depending on arrangements, +it is possible to form 16- and 17-digit strings. +What is the maximum 16-digit string for a "magic" 5-gon ring? +""" from itertools import permutations def solution(gon_side: int = 5) -> int: + """ + Find the maximum number for a "magic" gon_side-gon ring + + The gon_side parameter should be in the range [3, 5], + other side numbers aren't tested + + >>> solution(3) + 432621513 + >>> solution(4) + 426561813732 + >>> solution() + 6531031914842725 + >>> solution(6) + Traceback (most recent call last): + ValueError: gon_side must be in the range [3, 5] + """ if gon_side < 3 or gon_side > 5: raise ValueError("gon_side must be in the range [3, 5]") @@ -21,6 +78,15 @@ def generate_gon_ring(gon_side: int, perm: list[int]) -> list[int]: + """ + Generate a gon_side-gon ring from a permutation state + The permutation state is the ring, but every duplicate is removed + + >>> generate_gon_ring(3, [4, 2, 3, 5, 1, 6]) + [4, 2, 3, 5, 3, 1, 6, 1, 2] + >>> generate_gon_ring(5, [6, 5, 4, 3, 2, 1, 7, 8, 9, 10]) + [6, 5, 4, 3, 4, 2, 1, 2, 7, 8, 7, 9, 10, 9, 5] + """ result = [0] * (gon_side * 3) result[0:3] = perm[0:3] perm.append(perm[1]) @@ -36,6 +102,23 @@ def is_magic_gon(numbers: list[int]) -> bool: + """ + Check if the solution set is a magic n-gon ring + Check that the first number is the smallest number on the outer ring + Take a list, and check if the sum of each 3 numbers chunk is equal to the same total + + >>> is_magic_gon([4, 2, 3, 5, 3, 1, 6, 1, 2]) + True + >>> is_magic_gon([4, 3, 2, 6, 2, 1, 5, 1, 3]) + True + >>> is_magic_gon([2, 3, 5, 4, 5, 1, 6, 1, 3]) + True + >>> is_magic_gon([1, 2, 3, 4, 5, 6, 7, 8, 9]) + False + >>> is_magic_gon([1]) + Traceback (most recent call last): + ValueError: a gon ring should have a length that is a multiple of 3 + """ if len(numbers) % 3 != 0: raise ValueError("a gon ring should have a length that is a multiple of 3") @@ -48,4 +131,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_068/sol1.py
Add structured docstrings to improve clarity
def solution(n: int = 10**6) -> int: if n <= 0: raise ValueError("Please enter an integer greater than 0") phi = list(range(n + 1)) for number in range(2, n + 1): if phi[number] == number: phi[number] -= 1 for multiple in range(number * 2, n + 1, number): phi[multiple] = (phi[multiple] // number) * (number - 1) answer = 1 for number in range(1, n + 1): if (answer / phi[answer]) < (number / phi[number]): answer = number return answer if __name__ == "__main__": print(solution())
--- +++ @@ -1,6 +1,48 @@+""" +Totient maximum +Problem 69: https://projecteuler.net/problem=69 + +Euler's Totient function, φ(n) [sometimes called the phi function], +is used to determine the number of numbers less than n which are relatively prime to n. +For example, as 1, 2, 4, 5, 7, and 8, +are all less than nine and relatively prime to nine, φ(9)=6. + +n Relatively Prime φ(n) n/φ(n) +2 1 1 2 +3 1,2 2 1.5 +4 1,3 2 2 +5 1,2,3,4 4 1.25 +6 1,5 2 3 +7 1,2,3,4,5,6 6 1.1666... +8 1,3,5,7 4 2 +9 1,2,4,5,7,8 6 1.5 +10 1,3,7,9 4 2.5 + +It can be seen that n=6 produces a maximum n/φ(n) for n ≤ 10. + +Find the value of n ≤ 1,000,000 for which n/φ(n) is a maximum. +""" def solution(n: int = 10**6) -> int: + """ + Returns solution to problem. + Algorithm: + 1. Precompute φ(k) for all natural k, k <= n using product formula (wikilink below) + https://en.wikipedia.org/wiki/Euler%27s_totient_function#Euler's_product_formula + + 2. Find k/φ(k) for all k ≤ n and return the k that attains maximum + + >>> solution(10) + 6 + + >>> solution(100) + 30 + + >>> solution(9973) + 2310 + + """ if n <= 0: raise ValueError("Please enter an integer greater than 0") @@ -21,4 +63,4 @@ if __name__ == "__main__": - print(solution())+ print(solution())
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_069/sol1.py
Write beginner-friendly docstrings
def sum_digits(num: int) -> int: digit_sum = 0 while num > 0: digit_sum += num % 10 num //= 10 return digit_sum def solution(max_n: int = 100) -> int: pre_numerator = 1 cur_numerator = 2 for i in range(2, max_n + 1): temp = pre_numerator e_cont = 2 * i // 3 if i % 3 == 0 else 1 pre_numerator = cur_numerator cur_numerator = e_cont * pre_numerator + temp return sum_digits(cur_numerator) if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,6 +1,69 @@+""" +Project Euler Problem 65: https://projecteuler.net/problem=65 + +The square root of 2 can be written as an infinite continued fraction. + +sqrt(2) = 1 + 1 / (2 + 1 / (2 + 1 / (2 + 1 / (2 + ...)))) + +The infinite continued fraction can be written, sqrt(2) = [1;(2)], (2) +indicates that 2 repeats ad infinitum. In a similar way, sqrt(23) = +[4;(1,3,1,8)]. + +It turns out that the sequence of partial values of continued +fractions for square roots provide the best rational approximations. +Let us consider the convergents for sqrt(2). + +1 + 1 / 2 = 3/2 +1 + 1 / (2 + 1 / 2) = 7/5 +1 + 1 / (2 + 1 / (2 + 1 / 2)) = 17/12 +1 + 1 / (2 + 1 / (2 + 1 / (2 + 1 / 2))) = 41/29 + +Hence the sequence of the first ten convergents for sqrt(2) are: +1, 3/2, 7/5, 17/12, 41/29, 99/70, 239/169, 577/408, 1393/985, 3363/2378, ... + +What is most surprising is that the important mathematical constant, +e = [2;1,2,1,1,4,1,1,6,1,...,1,2k,1,...]. + +The first ten terms in the sequence of convergents for e are: +2, 3, 8/3, 11/4, 19/7, 87/32, 106/39, 193/71, 1264/465, 1457/536, ... + +The sum of digits in the numerator of the 10th convergent is +1 + 4 + 5 + 7 = 17. + +Find the sum of the digits in the numerator of the 100th convergent +of the continued fraction for e. + +----- + +The solution mostly comes down to finding an equation that will generate +the numerator of the continued fraction. For the i-th numerator, the +pattern is: + +n_i = m_i * n_(i-1) + n_(i-2) + +for m_i = the i-th index of the continued fraction representation of e, +n_0 = 1, and n_1 = 2 as the first 2 numbers of the representation. + +For example: +n_9 = 6 * 193 + 106 = 1264 +1 + 2 + 6 + 4 = 13 + +n_10 = 1 * 193 + 1264 = 1457 +1 + 4 + 5 + 7 = 17 +""" def sum_digits(num: int) -> int: + """ + Returns the sum of every digit in num. + + >>> sum_digits(1) + 1 + >>> sum_digits(12345) + 15 + >>> sum_digits(999001) + 28 + """ digit_sum = 0 while num > 0: digit_sum += num % 10 @@ -9,6 +72,17 @@ def solution(max_n: int = 100) -> int: + """ + Returns the sum of the digits in the numerator of the max-th convergent of + the continued fraction for e. + + >>> solution(9) + 13 + >>> solution(10) + 17 + >>> solution(50) + 91 + """ pre_numerator = 1 cur_numerator = 2 @@ -22,4 +96,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_065/sol1.py
Generate docstrings for script automation
from __future__ import annotations import numpy as np def get_totients(max_one: int) -> list[int]: totients = np.arange(max_one) for i in range(2, max_one): if totients[i] == i: x = np.arange(i, max_one, i) # array of indexes to select totients[x] -= totients[x] // i return totients.tolist() def has_same_digits(num1: int, num2: int) -> bool: return sorted(str(num1)) == sorted(str(num2)) def solution(max_n: int = 10000000) -> int: min_numerator = 1 # i min_denominator = 0 # φ(i) totients = get_totients(max_n + 1) for i in range(2, max_n + 1): t = totients[i] if i * min_denominator < min_numerator * t and has_same_digits(i, t): min_numerator = i min_denominator = t return min_numerator if __name__ == "__main__": print(f"{solution() = }")
--- +++ @@ -1,3 +1,33 @@+""" +Project Euler Problem 70: https://projecteuler.net/problem=70 + +Euler's Totient function, φ(n) [sometimes called the phi function], is used to +determine the number of positive numbers less than or equal to n which are +relatively prime to n. For example, as 1, 2, 4, 5, 7, and 8, are all less than +nine and relatively prime to nine, φ(9)=6. + +The number 1 is considered to be relatively prime to every positive number, so +φ(1)=1. + +Interestingly, φ(87109)=79180, and it can be seen that 87109 is a permutation +of 79180. + +Find the value of n, 1 < n < 10^7, for which φ(n) is a permutation of n and +the ratio n/φ(n) produces a minimum. + +----- + +This is essentially brute force. Calculate all totients up to 10^7 and +find the minimum ratio of n/φ(n) that way. To minimize the ratio, we want +to minimize n and maximize φ(n) as much as possible, so we can store the +minimum fraction's numerator and denominator and calculate new fractions +with each totient to compare against. To avoid dividing by zero, I opt to +use cross multiplication. + +References: +Finding totients +https://en.wikipedia.org/wiki/Euler's_totient_function#Euler's_product_formula +""" from __future__ import annotations @@ -5,6 +35,16 @@ def get_totients(max_one: int) -> list[int]: + """ + Calculates a list of totients from 0 to max_one exclusive, using the + definition of Euler's product formula. + + >>> get_totients(5) + [0, 1, 1, 2, 2] + + >>> get_totients(10) + [0, 1, 1, 2, 2, 4, 2, 6, 4, 6] + """ totients = np.arange(max_one) for i in range(2, max_one): @@ -16,10 +56,32 @@ def has_same_digits(num1: int, num2: int) -> bool: + """ + Return True if num1 and num2 have the same frequency of every digit, False + otherwise. + + >>> has_same_digits(123456789, 987654321) + True + + >>> has_same_digits(123, 23) + False + + >>> has_same_digits(1234566, 123456) + False + """ return sorted(str(num1)) == sorted(str(num2)) def solution(max_n: int = 10000000) -> int: + """ + Finds the value of n from 1 to max such that n/φ(n) produces a minimum. + + >>> solution(100) + 21 + + >>> solution(10000) + 4435 + """ min_numerator = 1 # i min_denominator = 0 # φ(i) @@ -36,4 +98,4 @@ if __name__ == "__main__": - print(f"{solution() = }")+ print(f"{solution() = }")
https://raw.githubusercontent.com/TheAlgorithms/Python/HEAD/project_euler/problem_070/sol1.py