The longest palindromic substring is the problem of finding a maximum-length contiguous substring of a given string that is also a palindrome. For example, the longest palindromic substring of "bananas" is "anana". The longest palindromic substring is not guaranteed to be unique; for example, in the string "abracadabra", there is no palindromic substring with length greater than three, but there are two palindromic substrings with length three, namely. "aca" and "ada. Write an efficient function that takes as its input a string (or an array of characters) and find the longest substring which is palindrome. You may assume the array is non-NULL and non-empty (i.e., it contains at least one element). Credit for this problem will be based in part on how efficient your solution is (in terms of big-oh runtime). Hint: You can use dynamic programming to efficiently implement your function. The function signature is: int longest PalSubstr(char *str);