题解 | #特殊乘法#

#include<bits/stdc++.h>
using namespace std;

int main() {
    string s1, s2;
    cin >> s1 >> s2;
    int sum = 0;
    for (int i = 0; i < s1.length(); i++) {
        for (int j = 0; j < s2.length(); j++) {
            sum += (s1[i] - '0') * (s2[j] - '0');
        }
    }
    cout << sum;
}