TASK DEFINITION: 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.
PROBLEM: ddnndgnddngdd

SOLUTION: dgnddngd

PROBLEM: accatatacta

SOLUTION: catatac

PROBLEM: vmkkmkkvmm

SOLUTION:
kkmkk