[BaekJoon][1225] 이상한 곱셈

BAEKJOON ONLINE JUDGE

1225 이상한 곱셈

https://www.acmicpc.net/problem/1225

#include <stdio.h>
 
char first[10001], second[10001];
 
int main()
{
    int i, j;
    long long int ans = 0;
 
    scanf("%s %s", first, second);
    
    for (i = 0; first[i] != '\0'; i++) {
        for (j = 0; second[j] != '\0'; j++) {
            ans += (first[i] - '0') * (second[j] - '0');
        }
    }
 
    printf("%lld\n", ans);
 
    return 0;
}