5. Longest Palindromic Substring

5. Longest Palindromic Substring

class Solution:
    def longestPalindrome(self, s: str) -> str:
        if len(s)<=1:return s
        ansl=1
        anss=s[0]

        dp=[[False for i in range(len(s))] for j in range(len(s))]
        for i in range(len(s)):
            dp[i][i]=True
            for j in range(i):
                if s[i]==s[j] and (i-j<=2 or dp[j+1][i-1]):
                    dp[j][i]=True
                    if i+1-j>ansl:
                        ansl=i+1-j
                        anss=s[j:i+1]
        return anss
                


    

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