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]: ppuppuuupuppupp
[A]: puppup


[Q]: kjjkkkkkkkk
[A]: kkkkkkkk


[Q]: xwwqqwwxwqqqq
[A]:
xwwqqwwx