Codewars - Descending Order

Salutations.

I'm posting Codewars challenges and my thought process in this series. I'm using JS and Node 18 whenever possible. Just for the sake of clarity, I'm making fair use of them.

Onto the next challenge from Codewars. In this one, we are tasked with developing a function that takes any integer as input. We have to order the digits from highest to lowest.

I start with this thought:

"Ok, I'll need to split the digits somehow. Maybe I should turn the integer to string first. Then split digits. Then order, then concatenate all, then revert to integer"

And so, it starts with a template:

function descendingOrder(n){

 // stringify
  number = n.toString();

 // split digits
  array = new Array(number.length);
  // code that fills array with digits {}

 //sort
  array.sort()

 // concatenate digits
  reverse = array.join('');

 // back to integer
  n = Number.parseInt(reverse);

  return n;
}

Much letters, such bore. And still not functional. So, what else do we need? Well, a loop that places the digits in the array for starters:

 // split digits
  array = new Array(number.length);
  for(i=0 ; i<number.length ; i++){
    array[i] = number.at(i);
  }

That should do it. Right?

GIF

Nope. One tiny little detail. The devil is in the details. And so are bugs. The sort function orders in ascending fashion by default. We need to "revert polarity". In essence, we need this. The default behavior is like this:

(a, b) => a - b

And we need:

(a, b) => b - a

All the ingredients combined:

function descendingOrder(n){
  number = n.toString();
  array = new Array(number.length);
  for(i=0;i<number.length;i++){
    array[i] = number.at(i);
  }
  array.sort((a,b)=>b-a)
  reverse = array.join('');
  n = Number.parseInt(reverse);
  return n;
}

Not the best, nor the simplest solution. But it does the job.

Cya. Drink water 💧💧💧.

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