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: qjqjjjjwqjqj

A: jjjj
****
Q: wfwtfwttttf

A: tttt
****
Q: vwbbwvvbwvv

A:
vwbbwv
****
