(python)leetcode刷题笔记05 Longest Palindromic Substring

5. Longest Palindromic Substring

Given a string s, find the longest palindromic substring in s. You may assume that the maximum length of s is 1000.

Example:

Input: "babad"

Output: "bab"

Note: "aba" is also a valid answer.

Example:

Input: "cbbd"

Output: "bb"

 class Solution:
     def solve(self,s,l,r):
         while r<len(s) and l>= and s[l]==s[r]:
             l-=
             r+=
         return s[l+:r]
     def longestPalindrome(self,s):
         if len(s) == :
             return
         max_string=''
         for i in range(len(s)):
             #奇数长度回文串如ababa
             tmp=self.solve(s,i,i)
             if len(tmp)>len(max_string):
                 max_string=tmp
             #偶数回文串如abba

             tmp=self.solve(s,i,i+)
             if len(tmp)>len(max_string):
                 max_string=tmp

         return max_string

Code

 def solve(s,l,r):
     while r<len(s) and l>= and s[l]==s[r]:
         l-=
         r+=
     return s[l+:r]
 def longestPalindrome(s):
     if len(s) == :
         return
     max_string=''
     for i in range(len(s)):
         #奇数长度回文串如ababa
         tmp=solve(s,i,i)
         if len(tmp)>len(max_string):
             max_string=tmp
         #偶数回文串如abba

         tmp=solve(s,i,i+)
         if len(tmp)>len(max_string):
             max_string=tmp

     return max_string

 print(longestPalindrome('ababa'))

Debug Code