题解 | #完全数计算#

#include <stdio.h>
#include <string.h>

int main() {

    int n;
    scanf("%d", &n);

    int k = 1;
    int sun = 0;
    int num = 0;

    while (k <= n) {
        for (int i = 1; i < k; i++) {
            if (k % i == 0)
                sun += i;
        }
        if (sun == k) {
            num++;
        }
        sun = 0;
        k++;
    }

    printf("%d", num);
    return 0;
}