#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define nl '\n'
 
void fastio() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
}
 
void solve() {
    int n; cin >> n;
    vector<int> v(n);
    for(int i = 0; i < n; i++) cin >> v[i];
 
 
    for (int i = 0; i < n - 1; i++) {
        if (v[i] <= 0 && v[i + 1] <= 0) {
            v[i] = abs(v[i]);
            v[i + 1] = abs(v[i + 1]);
        }
    }
 
    ll sum = accumulate(v.begin(), v.end(), 0LL);
    cout << sum << nl;
}
 
int main() {
    fastio();
    int t = 1;
    cin >> t;
    while (t--) {
        solve();
    }
    return 0;
}
 

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5
3
-1 -1 -1
5
1 5 -5 0 2
3
1 2 3
6
-1 10 9 8 7 6
2
-1 -1