#include <bits/stdc++.h>
using namespace std;

void solve() {
    int N;
    cin >> N;
    vector<int64_t> A(N);
    for (int i = 0; i < N; ++i) {
        cin >> A[i];
    }
    sort(begin(A), end(A));
    vector<int64_t> cumA(N + 1, 0);
    for (int i = 0; i < N; ++i) {
        cumA[i + 1] = A[i] * (i % 2 == 0 ? 1 : -1) + cumA[i];
    }
    int64_t ans = 0;
    for (int l = 0, r = N; l < r; ++l, --r) {
        ans = max(ans, abs(cumA[r] - cumA[l]));
    }
    cout << ans << endl;
}

int main() {
    int T;
    cin >> T;
    for (int i = 0; i < T; ++i) {
        solve();
    }
}