B

#include <bits/stdc++.h>
using namespace std;

int main()
{
    int t;
    cin>>t;

    while(t--)
    {
        int n;
        cin >> n;
        int a[n], b[n];
        for(int i = 0; i < n; i++) {
            cin >> a[i];
        }
        for(int i = 0; i < n; i++) {
            cin >> b[i];
        }

        sort(a, a+n);
        sort(b, b+n, greater<int>());

        int prev = a[0] + b[0], f=1;
        for(int i = 1; i < n && f; i++) {
            if(prev != a[i] + b[i]) {
                cout << -1 << endl;
                f=0;
            }
        }
        for(int i = 0; i < n && f; i++) {
            cout << a[i] << " ";
        }
        cout << endl;
        for(int i = 0; i < n && f; i++) {
            cout << b[i] << " ";
        }
        cout << endl;
    }
}