题解 | 判断质数

import math
n = int(input())
if n == 1:
    print('No')
elif n == 2:
    print('Yes')
elif n % 2 == 0:
    print('No')
else:
    b = int(math.isqrt(n)) + 1
    flag = True
    for i in range(3,b,2):
        if n % i == 0:
            flag = False
    print('Yes'if flag else'No')