class Solution: def getLongestPalindrome(self, A: str) -> int: n = len(A) if n < 2: return n max_length = 1 def expandAroundCenter(left: int, right: int) -> int: while left >= 0 and right < n and A[left] == A[right]: left -= 1 right += 1 return right - left - 1 for i in range(n): len1 = expandAroundCenter(i, i) # 单字符作为中心 len2 = expandAroundCenter(i, i + 1) # 两个字符之间的空隙作为中心(针对偶数长度的回文子串) max_length = max(max_length, len1, len2) return max_length