func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n, i, t, piles = 1;     bool flag = true;     cin >> n;     vector<int> s1, s2;     vector<int>::iterator it;     for (i = 0; i < n; i++) {       cin >> t;       s1.push_back(t);     }     sort(s1.begin(), s1.end());     while (flag) {       flag = false;       for (it = s1.begin(), i = 0; it != s1.end();) {         if ((*it) < i) {           flag = true;           s2.push_back(*it);           s1.erase(it);         } else {           it++;           i++;         }       }       if (flag) {         piles += 1;         s1.clear();         s1 = s2;         s2.clear();       }     }     cout << piles;     return 0;   }   