Problem: Valid Palindrome
Understand how to verify if a given string is a palindrome by converting characters to lowercase and ignoring non-alphanumeric symbols. Learn to implement a two-pointer approach that compares characters from both ends toward the center without extra space. This lesson teaches efficient string traversal and character comparison techniques for palindrome validation in Java, emphasizing in-place operations and linear time complexity.
We'll cover the following...
Statement
A phrase is considered a palindrome if, after converting all uppercase letters to lowercase and stripping all non-alphanumeric characters, it reads the same forward and backward. Alphanumeric characters include both letters and numbers.
Given a string s, return true if it qualifies as a palindrome after the transformations described above, or false otherwise.
Note: An empty string (which may result after removing all non-alphanumeric characters) is considered a palindrome.
Constraints:
s.length...