#include <cstdio>

#include <cmath>

#include <cstring>

#include <iostream>

#include <algorithm>

#include <queue>

#include <vector>

#include <map>



using namespace std;



typedef long long LL;


int T;
LL bit[50];
LL a[50];
int n;
LL dq1,dq2,ans,ans1,ans2,dq;

int main()

{
    scanf("%d",&T);
    bit[0]=1;
    for (int i=1;i<=30;++i) bit[i]=bit[i-1]*2;
    while (T--)
    {
        scanf("%d",&n);
        ans1=0;ans2=0;
        for (int i=1;i<=n;++i) scanf("%I64d",&a[i]);
        sort(a+1,a+n+1);
        for (int i=1;i<=n;++i)
        {
            dq=n-i;
            if (dq==0)
            {
                dq1=1;dq2=0;
            }
            else
            {
                dq1=bit[dq-1];dq2=bit[dq-1];
            }
            ans1+=dq1*a[i];
            ans2+=dq2*a[i];
        }
        ans=ans1-ans2;
        if (ans<0) ans=-ans;
        printf("%I64d\n",ans);
    }

    return 0;

}