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]: ppzggzzzzpggzz
[A]: zggz


[Q]: ppidipiddpp
[A]: pidip


[Q]: gabagbgbbb
[A]:
gabag