Leetcode5：Longest Palindromic Substring@Python

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"

动态规划法：以"ababae"为例：
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" alt="" width="548" height="207" />

 class Solution(object):
     def longestPalindrome(self, s):
         """
         :type s: str
         :rtype: str
         """
         sLength=len(s)
         begin=0
         length=0
         table=[]
         for i in range(sLength):
             tem=[]
             for j in range(sLength):
                 tem.append(0)
             table.append(tem)

         for i in range(sLength):
             table[i][i]=1

         for i in range(sLength-1):
             if s[i]==s[i+1]:
                 table[i][i+1]=1
                 begin=i
                 length=1

         for tem in range(1,sLength):
             for i in range(sLength-tem):
                 j=i+tem
                 if (s[i]==s[j] and table[i+1][j-1])==1:
                     table[i][j]=1
                     length=tem
                     begin=i

         return s[begin:begin+length+1]