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]: txxttppxpxtttxt
[A]: xtttx


[Q]: ddnndgnddngdd
[A]: dgnddngd


[Q]: llbklklkblkb
[A]:
lbklklkbl