How to write palindrome in JavaScript

Question

I wonder how to write palindrome in javascript, where I input different words and program shows if word is palindrome or not. For example word noon is palindrome, while bad

Answer 1

I think following function with time complexity of o(log n) will be better.

    function palindrom(s){
    s = s.toString();
    var f = true; l = s.length/2, len = s.length -1;
    for(var i=0; i < l; i++){
            if(s[i] != s[len - i]){
                    f = false; 
                    break;
            }
    }
    return f;

    }

console.log(palindrom(12321));