func_code_string: #include <bits/stdc++.h>   using namespace std;   int main(int argc, char **argv) {     int n;     unsigned long long ans;     string str;     cin >> n >> str;     map<int, vector<int> > myMap;     myMap[0].push_back(0);     int cur = 0;     ans = 0;     for (int i = 0; i < str.size(); i++) {       if (str[i] ==  0 ) {       } else {         cur++;       }       if (cur >= n && myMap.count(cur - n) != 0) {         ans += myMap[cur - n].size();       }       myMap[cur].push_back(i);     }     cout << ans << endl;     return 0;   }   