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]: wwnwdddwwdnn
[A]: wdddw


[Q]: jmmmzjzjjzmmm
[A]: zjjz


[Q]: rukkrrkkrrkkkru
[A]:
kkrrkkrrkk