#27469: _CPP
11030067@mail.hpsh.tp.edu.tw
(和平110級鄧雨珊)
int main(){
int t;
cin >> t;
while (t--){
int n, x, mx=0, mn=100;
cin >> n;
for (int i=0; i<n; i++){
cin >> x;
mx=max(mx, x);
mn=min(mn, x);
}
cout << (mx-mn)*2 <<endl;
}
}