Solution (leetcode-in-java 1.21 API)

java.lang.Object
- g0101_0200.s0125_valid_palindrome.Solution

```
public class Solution
extends Object
```
125 - Valid Palindrome.
Easy

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 * 10⁵
- s consists only of printable ASCII characters.

- Constructor Summary
  
  Constructors
  Constructor Description
  
  Solution()
- Method Summary
  
  All Methods Instance Methods Concrete Methods
  Modifier and Type Method Description
  
  boolean isPalindrome(String s)
  - Methods inherited from class java.lang.Object
    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail
- Solution
```
public Solution()
```

Method Detail

isPalindrome

public boolean isPalindrome(String s)