#include<iostream>
#include <bits/stdc++.h>

#define ld long double
#define ll long long
#define IO ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
using namespace std;
const int N = 30, mod = 998244353;
int basis[N];

bool add(int mask) {
    for (int i = 0; i < N; i++) {
        if ((mask & 1 << i) == 0)continue;
        if (!basis[i]) {
            basis[i] = mask;
            return true;
        }
        mask ^= basis[i];
    }
    return false;
}

vector<int> query(vector<int> &ans) {
    vector<int> res;
    int n = ans.size();
    for (int mask = 0; mask < (1 << n); mask++) {
        int cur = 0;
        for (int i = 0; i < n; i++) {
            if ((mask & 1 << i) != 0) {
                cur ^= ans[i];
            }
        }
        res.push_back(cur);
    }
    sort(res.begin(), res.end());
    return res;
}

void doWork() {
    memset(basis, 0, sizeof basis);
    int n;
    cin >> n;
    int cnt = 0;
    vector<int> a(1 << n, 0);
    for (int i = 1; i < (1 << n); i++) {
        cin >> a[i];
    }
    sort(a.begin(), a.end());
    for (auto i: a) {
        cnt += add(i);
    }

    if (cnt > n) {
        cout << -1 << "\n";
        return;
    }
    vector<int> ans(n - cnt, 0);
    for (int i = 0; i < N; i++) {
        if (basis[i]) {
            ans.push_back(basis[i]);
        }
    }
    if (a != query(ans)) {
        cout << "-1\n";
        return;
    }
    sort(ans.begin(), ans.end());
    for (auto i: ans)cout << i << " ";
    cout << "\n";
}

int main() {
    IO
    int t = 1;
    cin >> t;
    for (int i = 1; i <= t; i++) {
        //  cout << "Case #" << i << ": ";
        doWork();
    }
}