#ifdef DEBUG
#define _GLIBCXX_DEBUG
#endif
//#pragma GCC optimize("O3")
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;

#define X first
#define Y second



void solve()
{
    ll n;
    cin >> n;
    ll n2 = (1LL<<n);
    vector<ll> a(n2);
    for (ll i=1;i<n2;i++) cin >> a[i];
    sort(a.begin(),a.end());
    vector<ll> A;
    for (ll p=0;p<n;p++)
    {
        ll x = a[1];
        A.push_back(x);
        vector<ll> b;
        for (ll i=0;i<(1<<(n-p));i++)
        {
            if (x==0 and i%2!=0) continue;
            if (x!=0 and (x^a[i])<a[i]) continue;
            b.push_back(a[i]);
            //b.push_back(a[i]^x);
        }
        if (b.size()!=(1<<(n-p-1)))
        {
            cout << -1 << "\n";
            return;
        }
        vector<ll> c = b;
        sort(a.begin(),a.end());
        for (ll i=0;i<(1<<(n-p-1));i++)
        {
            b.push_back(b[i]^x);
        }
        sort(b.begin(),b.end());
        for (ll i=0;i<(1<<(n-p));i++)
        {
            if (a[i]!=b[i])
            {
                cout << -1 << "\n";
                return;
            }
        }
        a = c;
    }
    for (ll x: A) cout << x << " ";
    cout << "\n";
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
//#ifdef DEBUG
//    freopen("input.txt", "r", stdin);
//#endif
    ll T = 1;
    cin >> T;
    while (T--) solve();
    return 0;
}