125.valid-palindrome.ts

// @lc code=start
function isPalindrome(s: string): boolean {
	s = s.replace(/[^a-zA-Z0-9]/g, "").toLowerCase();

	let left = 0;
	let right = s.length - 1;

	while (left < right) {
		if (s[left] !== s[right]) return false;

		left++;
		right--;
	}

	return true;
}
// @lc code=end

console.log(isPalindrome("A man, a plan, a canal: Panama")); // true
console.log(isPalindrome("Not a palindrome")); // false
console.log(isPalindrome("Was it a car or a cat I saw?")); // true
console.log(isPalindrome("No 'x' in Nixon")); // true
console.log(isPalindrome("0P")); // false

/*
 * @lc app=leetcode id=125 lang=typescript
 *
 * [125] Valid Palindrome
 *
 * https://leetcode.com/problems/valid-palindrome/description/
 *
 * algorithms
 * Easy (50.67%)
 * Likes:    10285
 * Dislikes: 8541
 * Total Accepted:    4.2M
 * Total Submissions: 8.2M
 * Testcase Example:  '"A man, a plan, a canal: Panama"'
 *
 * 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 * 10^5
 * s consists only of printable ASCII characters.
 *
 *
 */