You are given a string input. You are to find the longest substring of input such that the reversal of the
substring is also a substring of input. In case of a tie, return the string that occurs earliest in input.
Note well: The substring and its reversal may overlap partially or completely. The entire original string
is itself a valid substring .
The best we can do is find a one character substring, so we implement the tiebreaker rule of taking the
earliest one first.
The first line of input gives a single integer, 1 ≤ N ≤ 10, the number of test cases. Then follow, for each
test case, a line containing between 1 and 50 characters, inclusive. Each character of input will be an
uppercase letter ('A'-'Z').
Output for each test case the longest substring of input such that the reversal of the substring is also a
substring of input
3 ABCABA XYZ XCVCX
ABA X XCVCX