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.

[EX Q]: iiddididijjiijd
[EX A]: didid

[EX Q]: vvvddvtvvvtd
[EX A]: tvvvt

[EX Q]: xbqqxxxbqxqxx
[EX A]:
xxx