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

namespace
{
int N;
int M;
char A[ 27 ][ 27 ];
char B[ 27 ][ 27 ];
char S[ 300 ];

int SearchA( int &iPos, const char C )
{
int i;

	for( i = 0; i < N; i++  )
	{
		iPos = 0;
		while( A[ i ][ iPos ] != '\0' )
		{
			if( A[ i ][ iPos ] == C )
			{
				return i;
			}

			iPos++;
		}
	}

	return - 1;
}

int SearchB( int &iPos, const char C )
{
int i;

	for( i = 0; i < M; i++  )
	{
		iPos = 0;
		while( B[ i ][ iPos ] != '\0' )
		{
			if( B[ i ][ iPos ] == C )
			{
				return i;
			}

			iPos++;
		}
	}

	return - 1;
}

int SetSet( char *X, const char *Y )
{
int i;

	i = 0;
	while( Y[ i ] != 0 )
	{
		X[ i ] = Y[ i ];
		i++;
	}

	return i;
}

}		// namespace

int main( int argc, char *argv[] )
{

int i;
int j;
int k;
int iStart;
int iEnd;
int iLen;
int iNum;
int iPos;
int iFlag;

	ios::sync_with_stdio( false );
	cin.tie( 0 );

	cin >> N;
	iLen = 0;
	for( i = 0; i < N; i++ )
	{
		cin >> A[ i ];
		iLen += strlen( A[ i ] );
	}

	cin >> M;
	j = 0;
	for( i = 0; i < M; i++ )
	{
		cin >> B[ i ];
		j += strlen( B[ i ] );
	}

	// Debug
	if( j != iLen )
	{
		cout << "Err" << endl;

		return 0;
	}

	iFlag = 0;
	iNum = 0;
	iStart = 100;
	iEnd = 100 + strlen( A[ iNum ] );
	strcpy( S + iStart, A[ iNum ] );
	j = SearchB( iPos, S[ iStart ] );
	while( j >= 0 && iPos > 0 )
	{
		iStart -= iPos;
		SetSet( S + iStart, B[ j ] );

		j = SearchA( iPos, S[ iStart ] );
		if( j < 0 || iPos <= 0 ) break;

		iStart -= iPos;
		SetSet( S + iStart, A[ j ] );
		j = SearchB( iPos, S[ iStart ] );
	}

	j = SearchB( iPos, S[ iEnd - 1 ] );
	while( j >= 0 )
	{
		k = strlen( B[ j ] );
		if( k <= 1 || iPos >= k - 1 ) break;

		strcpy( S + iEnd - iPos - 1, B[ j ] );
		iEnd += k - iPos - 1;
		j = SearchA( iPos, S[ iEnd - 1 ] );
		k = strlen( A[ j ] );
		if( j < 0 || k <= 1 || iPos >= k - 1 ) break;

		strcpy( S + iEnd - iPos - 1, A[ j ] );
		iEnd += k - iPos - 1;
		j = SearchB( iPos, S[ iEnd - 1 ] );
	}

	S[ iEnd ] = '\0';
	if( iEnd - iStart == iLen )
		cout << S + iStart << endl;
	else
		cout << - 1 << endl;

	return 0;
}