func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int t;     cin >> t;     while (t--) {       int n;       cin >> n;       string s;       cin >> s;       string w;       for (int i = 0; i <= 2 * n - 2; i = i + 2) {         w = w + s[i];       }       cout << w << endl;     }   }   