from itertools import *
while True:
    n = input()
    if n == 0:
        break
    a = [int(x) for x in raw_input().split(' ')]
    vis = [0 for x in range(1000)]
    for num in a:
        for x in set(permutations(str(num))):
            num_x = int("".join(x))
            vis[num_x] = vis[num_x] + 1
    ans = []
    for num in a:
        if(vis[num]==1):
            ans.append(num)
    ans.sort()
    first = 1
    ans_out = ""
    for num in ans:
        if first == 0:
            ans_out += " "
        if first == 1:
            first = 0
        ans_out += str(num)
    if ans_out == "":
        print "None"
    else:
        print ans_out