mirror of
https://github.com/TheAlgorithms/Python.git
synced 2024-11-24 05:21:09 +00:00
45 lines
927 B
Python
45 lines
927 B
Python
"""
|
|
Problem Statement:
|
|
The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17.
|
|
|
|
Find the sum of all the primes below two million.
|
|
"""
|
|
import math
|
|
from itertools import takewhile
|
|
|
|
|
|
def primeCheck(number):
|
|
if number % 2 == 0 and number > 2:
|
|
return False
|
|
return all(number % i for i in range(3, int(math.sqrt(number)) + 1, 2))
|
|
|
|
|
|
def prime_generator():
|
|
num = 2
|
|
while True:
|
|
if primeCheck(num):
|
|
yield num
|
|
num += 1
|
|
|
|
|
|
def solution(n):
|
|
"""Returns the sum of all the primes below n.
|
|
|
|
# The code below has been commented due to slow execution affecting Travis.
|
|
# >>> solution(2000000)
|
|
# 142913828922
|
|
>>> 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(solution(int(input().strip())))
|