Sorting numbers in descending order but with `0`s at the start

Question

I have a challenge in JavaScript that I’m trying to figure out for a while already.

Consider this array:

let arr = [0, 1, 0, 2, 0, 3, 0, 4, 0, 5]; 

I have to output this result:

arr = [0, 0, 0, 0, 0, 5, 4, 3, 2, 1] 

I’m following this line of logic to position the zeros in front, adjusting the index value:

arr.sort((x, y) => {     if (x !== 0) {         return 1;     }      if (x === 0) {         return -1;     }      return y - x; }); 

But I’m stuck at this result:

arr = [0, 0, 0, 0, 0, 1, 2, 3, 4, 5] 

Does anyone have any tips on how to solve this?

Answer 1

You could sort by the delta of b and a (for descending sorting) and take Number.MAX_VALUE, for falsy values like zero.

This:

Number.MAX_VALUE - Number.MAX_VALUE 

is equal to zero.

let array = [0, 1, 0, 2, 0, 3, 0, 4, 0, 5];    array.sort((a, b) => (b || Number.MAX_VALUE) - (a || Number.MAX_VALUE));    console.log(...array);