warmup12 min

Valid Palindrome

Given a string s, return true if it reads the same forwards and backwards considering only alphanumeric characters and ignoring case. Spaces, punctuation, and case are all ignored.

The two-pointer approach walks in from both ends, skipping non-alphanumeric characters.

isPalindrome("A man, a plan, a canal: Panama"); // true
isPalindrome("race a car");                      // false
isPalindrome(" ");                               // true (no alphanumerics)

Your code

Results

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javascript.data-structures