while True:
    try:
        num1 = int(input())
        arr1 = list(map(int, input().split()))
        num2 = int(input())
        arr2 = list(map(int, input().split()))
        arr = arr1+arr2
        list_arr = sorted(set(arr))
        res = ''.join(list(map(str,list_arr)))
        print(res)

    except:
        break