leetcode-680-验证回文字符串Ⅱ

 

 提交：O(N) O(1)

class Solution:
    def validPalindrome(self, s: str) -> bool:
        def helper(s):
            if s == s[::-1]:
                return True
            return False
        l,r = 0,len(s) - 1
        while l < r :
            if s[l] == s[r]:
                l += 1
                r -= 1
            else:
                if helper(s[l+1:r+1]) or helper(s[l:r]):
                    return True
                return False
        return True