Time Limit: 2 Seconds
Memory Limit: 65536 KB
You are given a number of case-sensitive strings of alphabetic characters,
find the largest string X, such that either X, or its inverse can be found as
a substring of any of the given strings.
The first line of the input file contains a single integer t (1 <= t <=
10), the number of test cases, followed by the input data for each test case.
The first line of each test case contains a single integer n (1 <= n <=
100), the number of given strings, followed by n lines, each representing one
string of minimum length 1 and maximum length 100. There is no extra white space
before and after a string.
There should be one line per test case containing the length of the largest
Source: Asia 2002, Tehran (Iran), Preliminary