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Valid Palindrome (easy)

Problem Statement

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: sentence = "A man, a plan, a canal, Panama!"
Output: true
Explanation: "amanaplanacanalpanama" is a palindrome.

Example 2:

Input: sentence = "Was it a car or a cat I saw?"
Output: true
Explanation: Explanation: "wasitacaroracatisaw" is a palindrome.

Constraints:

  • 1 <= s.length <= 2 * 10<sup>5</sup>
  • s consists only of printable ASCII characters.

Try it yourself

Try solving this question here:

Python3
Python3
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