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#!/usr/bin/env python3
""" Returns the nth prime number By Khalid Anwar
"""
def get_nth_prime_number(nth):
total_number_of_primes = 0
factor = 2
s = (nth * factor)
while total_number_of_primes < nth:
primes = make_prime(s)
total_number_of_primes = sum(primes[2:])
factor += 1
s = (nth * factor)
nth_prime_number = count_primes(primes, nth)
return nth_prime_number
""" using the Sieve of Eratosthenes
"""
def make_prime(k):
prime = bytearray([1]*k)
for i in range(2, k):
if prime[i] == 1:
for j in range(i, k):
if i*j < k:
prime[i*j] = 0
else:
break
return prime
""" Returns the n-th prime
"""
def count_primes(primes, nth):
count = 0
for k in range(2, len(primes)):
count += primes[k]
if count == nth:
return k
def main():
NTH = 10001
nth_prime_number = get_nth_prime_number(NTH)
print("The {}-th prime number is => {}".format(NTH, nth_prime_number))
if __name__ == "__main__":
main()
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