func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     std::ios::sync_with_stdio(false);     int T;     cin >> T;     while (T--) {       long long int n;       string second;       cin >> n;       cin >> second;       vector<char> v, v1;       int first = 0;       int f1 = 0;       int f2 = 0;       for (int i = n - 1; i >= 0; i--) {         if (first == 0 && second[i] ==  1 ) {           v.emplace_back(second[i]);         }         if (first == 0 && second[i] ==  0 ) {           v.emplace_back(second[i]);           first = 1;           f1 = i;           break;         }       }       for (int i = 0; i < n; i++) {         if (second[i] ==  0  && i < f1) {           v.emplace_back(second[i]);         }         if (second[i] ==  1 ) {           break;         }       }       reverse(v.begin(), v.end());       for (int i = 0; i < v.size(); i++) {         cout << v[i];       }       cout <<   n ;     }     return 0;   }   