题解 | 质数因子

import sys
import math
num = int(sys.stdin.readline())
number = num
ans = []

while num % 2 == 0:
    num = num / 2
    ans.append(2)
i = 3
while i <= math.sqrt(num):
    while num % i == 0:
        num = num / i
        ans.append(i)
    i = i + 2
if num > 2:
    ans.append(int(num))

print(*ans)

要点:

1.搜索到平方根为止

2.要考虑自身是质数的情况