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]: yyiikiiikiyy
[EX A]: ikiiiki

[EX Q]: iwvivviivwvwiw
[EX A]: ivvi

[EX Q]: ggggnnngxngggg
[EX A]:
gnnng