""" 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 """ def isprime(number: int) -> bool: """ Determines whether the given number is prime or not >>> isprime(2) True >>> isprime(15) False >>> isprime(29) True """ for i in range(2, int(number ** 0.5) + 1): if number % i == 0: return False return True 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) 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 isprime(num): primes.append(num) num += 1 else: num += 1 return primes[len(primes) - 1] if __name__ == "__main__": print(f"{solution() = }")