  /*  Karmanye vadhikaraste Ma Phaleshu Kadachana | Ma Karmaphalaheturbhurma Te Sangostvakarmani ||*/
//----------------------------------------------------------------------------------------------------------------//

/* this is begining have to survive more and go through long journey*/ 
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define vi vector<int>
#define vii vector<vi>
#define vll vector<long long>
#define mx(v) *max_element(v.begin(),v.end())
#define mn(v) *min_element(v.begin(),v.end())
#define st(v) sort(v.begin(),v.end())
#define bg .begin()
#define ed .end()
#define fi first
#define sc second
#define fr(i,l,u) for(i=l;i<u;i++)
#define rfr(i,l,u) for(i=l;i>u;i--)
#define ll long long int
#define lld long long double
#define uld unsigned long long int
#define pii pair<int,int>
#define flash ios_base::sync_with_stdio(0);cin.tie(NULL);
#define mod 1000000007
 
 void solve()
{
    ll n,i,x,sum=0,rem=0;
    cin>>n;
    vi v;
    fr(i,0,n)
    {
        cin>>x;
        sum+=x;
    }
    rem=sum%n;
    cout<<(n-rem)*rem<<endl;
    
    
}      
int main()
{
     int t;
   cin>>t;
   while(t--) solve();

}