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

int T,n,m,a[410],res;

bool cmp(int a,int b){
	return a>b;
}

int main(){
	freopen("happygameT1.in","r",stdin);
	freopen("happygameT1.out","w",stdout);
	
	scanf("%d",&T);
	for (int x=1;x<=T;x++){
		res=0;
		scanf("%d %d",&n,&m);
		for (int i=1;i<=n*m;i++) scanf("%d",&a[i]);
		sort(a+1,a+n*m+1,cmp);
		for (int i=1;i<=n;i++) res+=a[i];
		printf("%d\n",res);
	}
	
	return 0;
}