valid

"""
判断字符串是否回文
https://leetcode.com/problems/valid-palindrome/
"""
class :
    def isPalindrome(self, s: str) -> bool:
        if len(s) <= 1:
            return True
        start = 0
        end = len(s) - 1
        s = s.lower()
        while start < end:
            if not s[start].isalnum():
                start += 1
            elif not s[end].isalnum():
                end -= 1
            else:
                if s[start] != s[end]:
                    return False
                start += 1
                end -= 1
        return True


if __name__ == '__main__':
    s = Solution()
    assert s.isPalindrome("A man, a plan, a canal: Panama") == True
    assert s.isPalindrome("race a car") == False