25pts求调

#onclude<bits/stdc++.h>
using namespace std;
int main() {
    int T;
    cin >> T;
    while (T--) {
        int n;
        cin >> n;
        vector<int> vel(n);
        for (int &v : vel) {
            cin >> v;
        }
        sort(vel.begin(), vel.end());
        long long max_ = 0;
        for (int i = 1; i < n; ++i) {
            max_ += i;
        }
        
        cout << max_;
    }
    return 0;
}