The input consists of one or more sets of strings, followed by a final line containing only the value 00. Each set starts with a line containing an integer, nn, which is the number of strings in the set, followed by nn strings, one per line, sorted in nondescending order by length. None of the strings contain spaces. There is at least one and no more than 1515 strings per set. Each string is at most 2525 characters long.