> #include<iostream>
> #include<string>
> #include<fstream>
> #include<iomanip>
> 
> using namespace std;
> int main()
> {
>    //ifstream cin("0000.txt");
>    int n,aa[10000];
>    cin>>n;
>    for(int i=0;i<n;i++)
>    cin>>aa[i];
>    sort(aa,aa+n);
>    unsigned long long sum=0,temp;
>    for(int i=n-2;i>=0;i--)
>    {temp=(aa[i+1]-aa[i]);
>        sum+=temp*(n-i-1)*(i+1);        
>    }
>    cout<<sum*2<<endl;
>    //system("pause");
>    return 0;
> }