#include <iostream>
#include <string>
#include <vector>

using namespace std;

#define rep(i, a) for(int i=0;i<(a);i++)

int main(){
    int N,M; cin >> N;
    vector<string> A,B;
    for(int i=0;i<N;i++){
        string tmp; cin >> tmp;
        A.push_back(tmp);
    }
    cin >> M;
    for(int i=0;i<M;i++){
        string tmp; cin >> tmp;
        B.push_back(tmp);
    }
    for(int i=0;i<M;i++) cin >> B[i];

    for(int i=0;i<A.size();i++){
        for(int j=0;j<A[i].length()-1;j++){
            for(int k=0;k<B.size()-1;k++){
                for(int l=0;l<B.size();l++){
                    if(k==l) continue;
                    if(B[l].back() == A[i][j] && B[k].front() == A[i][j+1]){
                        string tmp = B[l] + B[k];
                        B[k] = tmp;
                        B.erase(B.begin()+l);
                    }else if(B[k].back() == A[i][j] && B[l].front() == A[i][j+1]){
                        string tmp = B[k] + B[l];
                        B[k] = tmp;
                        B.erase(B.begin()+l);
                    }
                }
            }
        }
    }

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