#include <bits/stdc++.h>
using namespace std;

void solve() {
     int n; cin >> n;
     vector<int> v(n);
     for(auto &x : v) cin >> x;
     sort(v.begin(), v.end());
     int ans = 0;
     for(int i = 0; i < n; i+=3) {
         ans += v[i] + v[i+1] + v[i+2];
     }
     
     cout << ans << "\n";
}

int main() {
    ios::sync_with_stdio(false);    
    cin.tie(nullptr);cout.tie(nullptr);

    int t; cin >> t;
    while(t--)
        solve();
    return 0;
}