#include<iostream>
#include<algorithm>
#include<cstdio>
using namespace std;
bool cmp(int a,int b){
    return a>b;
}
int main(){
    int t,n,a[20005];
    scanf("%d",&t);
    while(t--){
        scanf("%d",&n);
        for(int i=0;i<n;i++)
            scanf("%d",&a[i]);
        sort(a,a+n,cmp);
//        for(int i=0;i<n;i++)
//            cout<<a[i]<<endl;
        int sum = 0;
        for(int i=2;i<n;i+=3)
            sum += a[i];
        printf("%d\n",sum); 
    }
    return 0;
}