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

signed main(){
	int n;
	cin >> n;
	vector<string> a(n);
	for(int i = 0; i < n; i++)cin >> a[i];

	int m;
	cin >> m;
	vector<string> b(m);
	for(int i = 0; i < m; i++)cin >> b[i];

	vector<int> tmp(n), tmp1(m);

	for(int i = 0; i < n; i++)tmp[i] = i;
	for(int i = 0; i < m; i++)tmp1[i] = i;
	string s, s1;
	
	vector<string> ans;
	do{
		if(ans.size() > 1)break;
		s = "";
		for(int i = 0; i < n; i++)s += a[tmp[i]];	
		do{
			s1 = "";
			for(int j = 0; j < m; j++)s1 += b[tmp1[j]];
			if(s == s1){
				ans.push_back(s);
			}
		}while(next_permutation(tmp1.begin(), tmp1.end()));
	}while(next_permutation(tmp.begin(), tmp.end()));

	if(ans.size() == 1)cout << ans[0] << endl;
	else cout << -1 << endl;
}