Without ``` if s == s[::-1]: return len(s)```, my following codes got TLE

  • 0
    class Solution(object):
        def longestPalindromeSubseq(self, s):
            :type s: str
            :rtype: int
            if s == s[::-1]:
                return len(s)
            N = len(s)
            dp = [[0 for _ in range(N)] for __ in range(N)]
            for i in range(N):
                dp[i][i] = 1
            for i in range(N-1):
                dp[i][i+1] = 2 if s[i]==s[i+1] else 1
            for dis in range(2, N):
                for i in range(0, N-dis):
                    j = i+dis
                    if s[i]==s[j]:
                        dp[i][j] = dp[i+1][j-1]+2
                        dp[i][j] = max( dp[i+1][j], dp[i][j-1] )
            return dp[0][N-1]

    My above codes did from bottom to top. if s == s[::-1]: return len(s) seems only to address the test case with lots of same chars, such as 1000 d's. It is unfair.

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