题目:
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题解:
python
class Solution:
def isPalindrome(self, s: str) -> bool:
n = len(s)
left, right = 0, n - 1
while left < right:
while left < right and not s[left].isalnum():
left += 1
while left < right and not s[right].isalnum():
right -= 1
if left < right:
if s[left].lower() != s[right].lower():
return False
left, right = left + 1, right - 1
return True