leetcode3

题目链接：https://leetcode-cn.com/problems/longest-palindromic-substring/

代码：

class Solution(object):
    def longestPalindrome(self, s):
        """
        :type s: str
        :rtype: str
        """
        n = len(s)

        m,l,r = 0,0,0

        for i in range(n):
            # odd case
            for j in range(min(i+1,n-i)):
                if s[i-j] != s[i+j]:
                    break
                if 2*j + 1 > m :
                    m = 2 * j + 1
                    l = i-j
                    r = i+j


            if i+1 < n and s[i] == s[i+1]:
                for j in range(min(i+1,n-i-1)):
                    if s[i-j] != s[i+j+1]:
                        break
                    if 2 * j + 2 > m :
                        m = 2*j +2
                        l = i-j
                        r = i+j+1
        return s[l:r+1]