#include <stdio.h>
#include<math.h>
#include<bits/stdc++.h>
    int  main ()
    {

        int ion, i,n,testCase, sum=0;
       scanf("%d", &testCase);
       ion=1;
       while (ion<=testCase)
        {
        scanf("%d", &n);
        int number[n];
        for (i = 0; i < n; ++i)
	        {scanf("%d", &number[i]);}
        sort(number,number+n);

      for (i=0; i<n; i+=2){
        sum=sum+number[i];
        }
      printf("%d\n", sum);
      sum=0;
      i++;
    }
    }