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Longest Palindromic Substring - Python - Leetcode 5

 Given a string s, return the longest palindromic substring in s.

 

Example 1:

Input: s = "babad"
Output: "bab"
Explanation: "aba" is also a valid answer.

Example 2:

Input: s = "cbbd"
Output: "bb"


class Solution:

    def longestPalindrome(self, s: str) -> str:

        p = ""

        plen = 0

        

        for i in range(len(s)):

            #odd check

            l,r = i,i

            while l>=0 and r<len(s) and s[l]==s[r]:

                if (r-l+1)>plen:

                    p = s[l:r+1]

                    plen=r-l+1  

                l-=1

                r+=1

                

            #even check

            l,r = i,i+1

            while l>=0 and r<len(s) and s[l]==s[r]:

                if (r-l+1)>plen:

                    p = s[l:r+1]

                    plen=r-l+1  

                l-=1

                r+=1

        return p

            

            

    Explaination :















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