How to check if string is Palindrome in Javascript

Here is how to check if a given string is a palindrome (same when reversed) in Javascript

function isPalindrome(str) {
  // We remove all non-alphanumeric characters, convert to lower case and trim spaces
  str = str.replace(/[\W_]/g, '').toLowerCase();

  // We compare the original string with its reverse
  return (str == str.split('').reverse().join(''));
}

console.log(isPalindrome("A man, a plan, a canal: Panama"));  // Should print: true
console.log(isPalindrome("not a palindrome"));  // Should print: false

Idea: turn in intro array, reverse the array and join it back. Then compare with original

• We remove all non-alphanumeric characters (including spaces) using a regular expression
• We convert the string to lower case.
• Then split the string into an array of characters
• Reverse the array, and join it back into a string.
• If the resulting string is equal to the original string, then it is a palindrome.

What is a palindrome

A palindrome is a word, phrase, number, or other sequences of characters that reads the same forward and backward, ignoring spaces, punctuation, and capitalization. In other words, it’s symmetrical along its center.

Examples of palindromic words include “radar”, “level”, “rotor”, “madam”, and “racecar”. An example of a palindromic phrase could be “Able was I ere I saw Elba”. This phrase remains the same when read backward if you ignore spaces, punctuation, and capitalization.

In the context of programming, a common problem is to determine whether a given string is a palindrome or not. This is typically done by comparing the string to its reverse and checking if they are equal.