题解 | #特殊乘法#

#include <cstdio>
//讨论区gsnace得思路，太牛了
int main () {
    int a = 0, b = 0;
    char c;
    while (' ' != (c = getchar()))
        a += c - '0';
    while (' ' <= (c = getchar()))
        b += c - '0';
    printf("%d", a * b);
}