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: xnnxxxxnxx

A: nxxxxn
****
Q: zzaqzqzqaz

A: zaqzqzqaz
****
Q: gthhhggtthtght

A:
hhh
****