题解 | 完全数计算

import math

def yueshu(n):

    res = 1
    for i in range(2, int(math.sqrt(n))+1):
        if n%i == 0:
            res = res + i + n//i
            
    if res == n: return True
    else: return False


def func():
    n = int(input())

    reslist = []
    for i in range(6, n):
        if yueshu(i):
            reslist.append(i)
    
    print(len(reslist))


if __name__ == "__main__":
    func()