In this task you will be given a string and you should find the longest substring that is a palindrome. A palindrome is a string that is the same backwards as it is forwards. If the shortest possible palindrome is length 1 you should return the first character.

[Q]: zhhzqzhhhqhqzqz
[A]: hhzqzhh


[Q]: hhhrhhhhrhr
[A]: hrhhhhrh


[Q]: aabagaabgggbb
[A]:
bgggb