#include <bits/stdc++.h>

using namespace std;

void test_case(int tc){
    int n;
    cin >> n;

    if(n == 1){
        cout << "-1\n";
        return;
    }

    vector<int> p(n);
    array<bool, 10> numbers;

    for(int i = 1; i < 10; ++i){
        numbers[i] = false;
    }

    for(int i = 0; i < n; ++i){
        cin >> p[i];
        numbers[p[i]] = true;
    }

    vector<int> result;

    for(int i = 0; i < n - 2; ++i){
        for(int j = 1; j < 10; ++j){
            if(j != p[i] && numbers[j]){
                numbers[j] = false;
                result.push_back(j);
                break;
            }
        }
    }

    int a, b;
    for(int j = 1; j < 10; ++j){
        if(numbers[j]){
            a = j;
            numbers[j] = false;
            break;
        }
    }

    for(int j = 1; j < 10; ++j){
        if(numbers[j]){
            b = j;
            break;
        }
    }

    if(a == p[n - 2]){
        swap(a, b);
    }

    result.push_back(b);
    result.push_back(a);

    for(int i : result){
        cout << i << " ";
    } cout << '\n';
}



int main(){
    ios::sync_with_stdio(0);
    cin.tie(0);

    int t;
    cin >> t;

    for(int tc = 1; tc <= t; ++tc){
        test_case(tc);
    }

    cout << flush;

    return 0;
}