func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     vector<pair<int, int> > v;     int n, i, c = 1, ans = 0;     vector<pair<int, int> >::iterator it;     cin >> n;     for (i = 0; i < n; i++) {       int x, y;       cin >> x >> y;       v.push_back(make_pair(y, x));     }     sort(v.begin(), v.end());     for (i = n - 1; i >= 0; i--) {       if (c == 0) {         break;       }       c = c - 1 + v[i].first;       ans = ans + v[i].second;     }     cout << ans << endl;   }   