func_code_string: #include <bits/stdc++.h>   int c[1000001];   char str[1000001];   int len;   int ct;   long long ans;   int main() {     int k;     int i;     scanf( %d , &k);     scanf( %s , str);     len = strlen(str);     if (k == 0) {       for (i = 0; i < len; i++) {         if (str[i] ==  0 )           ct++;         else {           ans += (long long)ct * (long long)(ct + 1) / 2;           ct = 0;         }       }       ans += (long long)ct * (long long)(ct + 1) / 2;     } else if (k > 0) {       for (i = 0; i < len; i++) {         if (str[i] ==  1 ) ct++;         c[ct]++;       }       ans = c[k];       for (i = k; i <= len; i++) ans += (long long)c[i] * (long long)c[i - k];     }     printf( %I64d n , ans);     scanf(   );   }   