zoj2883

#include<iostream>#include<algorithm>using namespace std;int cost[20010];int main(){    int ncase,num,i,expend;    cin>>ncase;    while(ncase--)    {    expend=0;    cin>>num;    for(i=0;i<num;i++)    {    cin>>cost[i];    }    sort(cost,cost+num);    if(num<3)expend=0;    else    {    if(num%3==0)    {    for(i=0;i<num;i=i+3)    expend+=cost[i];    }    if(num%3==1)    {    for(i=1;i<num;i=i+3)    expend+=cost[i];    }    if(num%3==2)    {    for(i=2;i<num;i=i+3)    expend+=cost[i];    }    }    cout<<expend;    if(ncase)cout<<endl;    }    return 0;}