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;