[LeetCode][Python3] 204. Count Primes

Problem :

https://leetcode.com/problems/count-primes/

My Solution :

class Solution:

def countPrimes(self, n):

"""

:type n: int

:rtype: int

"""

is_prime = [1]*n

for i in range(2, int(n**0.5)+1):

if is_prime[i]:

for j in range(i**2, n, i):

is_prime[j] = 0

return sum(is_prime[2:])

Comment :

에라토스테네스의 체 문제이다.