import sys
from itertools import accumulate
from collections import Counter

def solve():
    n = int(input())

    cnt = 0
    words = []

    for i in range(n):
        s = input()
        cnt += len(s)
        words.append(s)

    if len(words) == 1:
        print(words[0])
        return

    nxt = [-1]*cnt
    cor = dict()
    rev = dict()
    num = 0

    for word in words:
        for i, ch in enumerate(word):
            cor[ch] = num
            rev[num] = ch

            if i + 1 < len(word):
                nxt[num] = (num + 1) % cnt

            num += 1

    m = int(input())

    for i in range(m):
        s = input()

        for i, ch in enumerate(s[:-1]):
            nxt[cor[ch]] = cor[s[i + 1]] % cnt

    # print(nxt)

    if nxt.count(-1) > 1:
        print(-1)
    else:
        for i in range(cnt):
            ans = dfs(nxt, rev, i, cnt, '')

            if ans:
                print(ans)
                return

def dfs(nxt, rev, i, cnt, ans):
    if i == -1:
        if len(ans) == cnt:
            return ans
        else:
            return False

    return dfs(nxt, rev, nxt[i], cnt, ans + rev[i])

if __name__ == '__main__':
    solve()