[Leetcode] Longest Palindromic Substring [Unsolved]

Given a string S, find the longest palindromic substring in S. You may assume that the maximum length of S is 1000, and there exists one unique longest palindromic substring.

This problem is an implementation of Manacher's Algorithm.

Reference:

Chinese: http://www.felix021.com/blog/read.php?2040

English: http://leetcode.com/2011/11/longest-palindromic-substring-part-ii.html

代码参考：http://blog.youkuaiyun.com/tingmei/article/details/8053521