#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int t;
  cin >> t;
  while (t--) {
    int n;
    cin >> n;
    int arr[n];
    for (int i = 0; i < n; i++) cin >> arr[i];
    long long tar = arr[0], sum = 0;
    int pos = (arr[0] > 0 ? 1 : -1);
    for (int i = 1; i < n; i++) {
      if (arr[i] * pos < 0) {
        sum += tar;
        tar = arr[i];
      }
      pos = (arr[i] > 0 ? 1 : -1);
      if (arr[i] > tar) tar = arr[i];
    }
    sum += tar;
    cout << sum << endl;
  }
}
