//实验3.4
#include <iostream>
using namespace std;

int main() {
    int a;
    cout << "请输入一个整数: ";
    cin >> a;

    int b = 0;
    while (a!= 0) {
        b += a % 10;
        a /= 10;
    }

    cout << "各位数字之和为: " << b << endl;
    return 0;
}