#include <stdio.h>
#include <string.h>
#define N 100010
typedef long long LL;
int main() {
    char num1[N] = "";
    char num2[N] = "";
    LL a[N], b[N];
    LL sum = 0, ans = 1;
    scanf("%s", num1);
    scanf("%s", num2);
    for (int i = 0; i < strlen(num1); i ++ )
        a[i] = num1[i] - '0';
    for (int i = 0; i < strlen(num2); i ++ )
        b[i] = num2[i] - '0';
    for (int i = 0; i < strlen(num1); i ++ ) {
        for (int j = 0; j < strlen(num2); j ++ ) {
            ans = a[i] * b[j];
            sum += ans;
        }
    }
    printf("%lld\n", sum);
    return 0;
}