func_code_string: #include <bits/stdc++.h>   #pragma warning(disable : 4996)   using namespace std;   int n, m;   char a[2000000], b[2000000];   int main() {     int i, j, k;     scanf( %s%s , a, b);     n = strlen(a), m = strlen(b);     int now = 0;     for (i = 0; i < m; i++) {       if (b[i] == a[now]) {         now++;         if (now == n) break;       }     }     int c1, c2;     c1 = i;     now = n - 1;     for (i = m - 1; i >= 0; i--) {       if (b[i] == a[now]) {         now--;         if (now == -1) break;       }     }     c2 = i;     printf( %d , max(0, c2 - c1));     return 0;   }   