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A phrase is a palindrome if, after converting all uppercase letters into lowercase letters and removing all non-alphanumeric characters, it reads the same forward and backward. Alphanumeric characters include letters and numbers.
Given a string s, return true if it is a palindrome, or false otherwise.
Example 1:
Input: s = "A man, a plan, a canal: Panama" Output: true Explanation: "amanaplanacanalpanama" is a palindrome.
Example 2:
Input: s = "race a car" Output: false Explanation: "raceacar" is not a palindrome.
Example 3:
Input: s = " " Output: true Explanation: s is an empty string "" after removing non-alphanumeric characters. Since an empty string reads the same forward and backward, it is a palindrome
Constraints:
1 <= s.length <= 2 * 105sconsists only of printable ASCII characters.
Python
from typing import List
class Solution:
def maxArea(self, height: List[int]) -> int:
maxSum = 0
left, right = 0, len(height) - 1
while left < right:
maxSum = max(maxSum, (right - left) *
min(height[left], height[right]))
if height[left] < height[right]:
left += 1
else:
right -= 1
return maxSum
Height = [1, 8, 6, 2, 5, 4, 8, 3, 7]
print(Solution().maxArea(Height))
![[Leetcode] 0020. Valid Parentheses](https://hogantechs.com/wp-content/uploads/2025/02/1-1024x577.jpg)
