2019-07-16 23:09:53 +00:00
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"""
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2020-10-08 05:57:47 +00:00
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Problem 7: https://projecteuler.net/problem=7
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2019-07-16 23:09:53 +00:00
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By listing the first six prime numbers:
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2, 3, 5, 7, 11, and 13
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We can see that the 6th prime is 13. What is the Nth prime number?
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"""
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2019-10-05 05:14:13 +00:00
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2020-10-08 05:57:47 +00:00
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def isprime(number: int) -> bool:
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"""Determines whether the given number is prime or not"""
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2019-07-16 23:09:53 +00:00
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for i in range(2, int(number ** 0.5) + 1):
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if number % i == 0:
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return False
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return True
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2020-10-08 05:57:47 +00:00
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def solution(nth: int = 10001) -> int:
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2019-07-16 23:09:53 +00:00
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"""Returns the n-th prime number.
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2019-08-19 13:37:49 +00:00
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2019-07-16 23:09:53 +00:00
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>>> solution(6)
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13
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>>> solution(1)
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2
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>>> solution(3)
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5
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>>> solution(20)
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71
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>>> solution(50)
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229
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>>> solution(100)
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541
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2020-10-08 05:57:47 +00:00
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>>> solution()
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104743
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2019-07-18 17:05:14 +00:00
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>>> solution(3.4)
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5
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>>> solution(0)
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Traceback (most recent call last):
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...
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2020-10-08 05:57:47 +00:00
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ValueError: Parameter nth must be greater or equal to one.
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2019-07-18 17:05:14 +00:00
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>>> solution(-17)
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Traceback (most recent call last):
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...
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2020-10-08 05:57:47 +00:00
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ValueError: Parameter nth must be greater or equal to one.
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2019-07-18 17:05:14 +00:00
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>>> solution([])
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Traceback (most recent call last):
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...
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2020-10-08 05:57:47 +00:00
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TypeError: Parameter nth must be int or passive of cast to int.
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2019-07-18 17:05:14 +00:00
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>>> solution("asd")
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Traceback (most recent call last):
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...
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2020-10-08 05:57:47 +00:00
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TypeError: Parameter nth must be int or passive of cast to int.
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2019-07-16 23:09:53 +00:00
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"""
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2019-07-18 17:05:14 +00:00
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try:
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2020-10-08 05:57:47 +00:00
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nth = int(nth)
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2020-05-22 06:10:11 +00:00
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except (TypeError, ValueError):
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2020-10-08 05:57:47 +00:00
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raise TypeError(
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"Parameter nth must be int or passive of cast to int."
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) from None
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if nth <= 0:
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raise ValueError("Parameter nth must be greater or equal to one.")
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2019-07-16 23:09:53 +00:00
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primes = []
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num = 2
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2020-10-08 05:57:47 +00:00
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while len(primes) < nth:
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2019-07-16 23:09:53 +00:00
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if isprime(num):
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primes.append(num)
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num += 1
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else:
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num += 1
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return primes[len(primes) - 1]
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if __name__ == "__main__":
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2019-08-19 13:37:49 +00:00
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print(solution(int(input().strip())))
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