Game Of Strengths

#include <iostream>
#include <bits/stdc++.h>
using namespace std;
 
int main() {
     ios_base::sync_with_stdio(false);
    cin.tie(NULL);
 int num;
 cin >> num;          // Reading input from STDIN
 while(num--)
 {
   
     int n;
     cin>>n;
     int A[n];
     int ma=0;
     long long sum=0;
     for(int i=0;i<n;++i)
     {
     cin>>A[i];
     if(ma<A[i])
     ma=A[i];
     sum=sum+A[i];
     }
     sort(A,A+n);
     long long res=0;
     for(int i=0;i<n-1;++i)
     {
         for(int j=i+1;j<n;++j)
         {
             res=res+abs(A[i]-A[j]);
         }
       
     }
     res=res*ma;
     cout<<res%1000000007<<"\n";
 }
}