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: oxoxoaoxaaxxoaa

A: oxoxo
****
Q: zhhzqzhhhqhqzqz

A: hhzqzhh
****
Q: ykknknyknkynkky

A:
knyknkynk
****