#include <bits/stdc++.h>

using namespace std;

#include "debug.h"

void solve() {
        int n;
        cin >> n;

        map<int, int> cnt;
        for (int i = 0; i < n; ++i) {
                int x;
                cin >> x;
                ++cnt[x];
        }

        int a1 = min(cnt[1], cnt[-1] / 2);
        cnt[1] -= a1;
        cnt[-1] -= 2 * a1;

        int a2 = cnt[1] / 3;
        cnt[1] -= 3 * a2;

        int a3 = min(cnt[-1], cnt[0]);
        cnt[-1] -= min(cnt[-1], 2 * a3);

        int a4 = cnt[-1] / 3;
        cnt[-1] -= 3 * a4;

        cout << a1 + a2 - (a4 + cnt[-1]) << '\n';
}

int32_t main() {
        ios_base::sync_with_stdio(false);
        cin.tie(0);

        int tc = 1;
        cin >> tc;

        while (tc--) {
                solve();
        }
}