// Pratiyush Mishra

#include <bits/stdc++.h>
#define ll long long int
using namespace std;


void mainSolve()
{
    ll n;
    cin >> n;
    vector<ll> v(n);
    for (int i = 0; i < n; i++)
        cin >> v[i];
    ll x = 0;
    for (int i = 0; i < n; i++)
    {
        ll val;
        if (i % 2 == 0)
            val = v[i] % 2;
        else
            val = v[i] / 2;
        x ^= val;
    }
    if (x)
        cout << "CHEF\n";
    else
        cout << "CHEFINA\n";
}

int main()
{
#ifndef ONLINE_JUDGE
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
    int t;
    cin >> t;
    while (t--)
    {
        mainSolve();
    }
    return 0;
}