#include <iostream>
#include <stdio.h>
#include <algorithm>
#include <math.h>

using namespace std;

int t , n , a[40];
long long ans , c[40][40];

inline long long cal( int x , int y )
{
    return c[x][y];
}

int main()
{
    cin >> t;
    c[0][0] = 1;
    for( register int i = 1 ; i <= 30 ; i++ )
    {
        c[i][0] = 1;
        for( register int j = 1 ; j <= 30 ; j++ )
            c[i][j] = c[i - 1][j] + c[i - 1][j - 1];
    }
    while( t-- )
    {
        cin >> n;
        for( register int i = 1 ; i <= n ; i++ ) cin >> a[i];
        sort( a + 1 , a + n + 1 );
        ans = 0;
        for( register int i = 1 ; i <= n ; i++ )
            for( register int j = 1 ; j <= n ; j++ )
            {
                int t = n - j;
                if( t < i ) continue;
                if( i & 1 ) ans += cal( t , i ) * a[j];
                else ans -= cal( t , i ) * a[j];
            }
        for( register int i = 1 ; i <= n ; i++ )
            ans -= a[i];
        cout << abs( ans ) << endl;
    }
    return 0;
}