Check if String is Palindrome

JavaScript

Technical Specification

Check whether a given string reads the same forwards and backwards. Ignore case and non-alphanumeric characters.

Input/Output Samples

Input:"madam"

Output:true

Input:"A man, a plan, a canal: Panama"

Output:true

Input:"hello"

Output:false

Optimal Logic Path

function isPalindrome(str) {
  const cleaned = str.toLowerCase().replace(/[^a-z0-9]/g, "");
  const reversed = cleaned.split("").reverse().join("");
  return cleaned === reversed;
}

Architectural Deep-Dive

By cleaning the string we ignore spaces and punctuation. Then we reverse and compare to check if it’s a palindrome.