func_code_string: #include <bits/stdc++.h>   using namespace std;   map<long long int, long long int> m;   int main() {     long long int t;     cin >> t;     while (t--) {       long long int n;       cin >> n;       long long int a[n];       for (long long int i = 0; i < n; i++) cin >> a[i];       sort(a, a + n);       long long int x = 0, y = n - 1, iff = 1;       vector<long long int> v;       for (long long int i = 0; i < n; i++) {         if (iff) {           v.push_back(a[y]);           y--;           iff = 0;         } else {           v.push_back(a[x]);           x++;           iff = 1;         }       }       for (long long int i = n - 1; i >= 0; i--) cout << v[i] <<    ;       cout << endl;     }   }   