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: yyunyuynuny

A: unyuynu
****
Q: uvvvnnuunnvuu

A: vnnuunnv
****
Q: cgyccyycgcgc

A:
cgcgc
****