#include<bits/stdc++.h>
using namespace std;
#define il inline
#define rg register
#define int long long
il int read()
{
    int re=0,k=1;char ch=getchar();
    while(ch>'9'||ch<'0'){if(ch=='-')k=-1;ch=getchar();}
    while(ch<='9'&&ch>='0'){re=re*10+ch-48;ch=getchar();}
    return re*k;
}

il void write(int x)
{
    if(x<0)return putchar('-'),write(-x),void();
    if(x<10)return putchar(x+48),void();
    return write(x/10),write(x%10),void();
}
int n,a[100005],s[100005],sum,ans;
signed main()
{
    int T=read();
    while(T--)
    {
        ans=0;
        int n=read();
        for(int i=1;i<=n;i++)
            sum+=a[i]=read();
        sort(a+1,a+n+1);
        for(int i=1;i<=n;i++)
        {
            ans+=sum-a[i]*(n-i+1);
            sum-=a[i];
        }
        write(ans);puts("");
    }
}