#include<bits/stdc++.h>
#define ll long long
#define endl "\n"
using namespace std;

int main() {
    ios_base::sync_with_stdio(0);cin.tie(0);
    int t,a,b,x;   cin >> t; 
    while(t--){
        cin >> a;
        map<int,int>m;
        while(a--){
            cin >> x;
            m[x]++;
        }
        if(m[0] || m[1]==3 && m[-1]==3)    cout << 0 << endl;
        else{
            if(m[-1]%2!=0 && m[-1]<=(a/3*2+1))   cout << a/3 - 1 << endl;
            else if(m[-1]%2!=0 && m[-1]>(a/3*2-1))   cout << a - m[-1] << endl;
            else if(m[-1]%2==0 && m[1]!=0)    cout << a/3 << endl;
            else    cout << -a/3 << endl;
        }
    }
  return 0;
}