#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using P = pair<int, int>;
const long long MOD = 1000000007;
const long long INF = 1LL << 60;
const int INT_INF = 1000000000;
int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
void solve() {
  int n;
  cin >> n;
  vector<ll> a(n);
  for (auto &ai : a) cin >> ai;
  bool positive;
  if (a[0] < 0)
    positive = false;
  else
    positive = true;
  ll sum = 0;
  ll tmp = a[0];
  for (int i = 1; i < n; i++) {
    if (positive) {
      if (a[i] > 0) {
        tmp = max(tmp, a[i]);
      } else {
        sum += tmp;
        tmp = a[i];
        positive = false;
      }
    } else {
      if (a[i] > 0) {
        sum += tmp;
        tmp = a[i];
        positive = true;
      } else {
        tmp = max(tmp, a[i]);
      }
    }
  }
  sum += tmp;
  cout << sum << endl;
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  int t;
  cin >> t;
  for (int i = 0; i < t; i++) solve();
  return 0;
}
