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: pppptttptpppp

A: ptttp
****
Q: vnanvavnan

A: nanvavnan
****
Q: hkkkyhhkkyk

A:
kkk
****