kaprekar.js

kaprekar.js

var num = "174";
kaprekar(num);

function kaprekar(num){

    s1 = parseInt(num.split("").sort().join(""));
    s2 = parseInt(num.split("").sort(function(a,b){return b-a}).join(""));
    n = (s1 > s2) ? s1 -s2 : s2 - s1;
    (s1 > s2) ? console.log(s1 + " - " + s2 + " = " + n) : console.log(s2 + " - " + s1 + " = " + " = " + n);
    if(n === parseInt(num)){
        return n;
    } else {
        console.log(n);
        return kaprekar(new String(n));
    }
}