while True:
    try:
        n = int(input())
        if n == 0:break
        a = input().split()
        b = []
        for n in a:
            n = list(n)
            n.sort()
            n = "".join(n)
            b.append(n)
        c = []
        for i in range(len(a)):
            if b.count(b[i]) == 1:
                c.append(int(a[i]))
        if len(c) == 0:
            print("None")
        else:
            c.sort()
            for n in c:
                print(n,end=" ")
            print("")

    except EOFError:
        break