given array of numbers, return array of numbers that tells how many numbers to the right are smaller than current value

smaller-than-me.js

function smaller(nums) {
  /** developer comment:
    - we have to return the amount of numbers that are smaller than arr[i] to the right.
    - example: smaller([5, 4, 3, 2, 1]) === [4, 3, 2, 1, 0] or smaller([1, 2, 0]) === [1, 1, 0]
    - go over each elemt
    - cut with slice base on current index
    - filter which one is smaller then current value
    - use lenght to count how smaller than me?
  **/
  let res = nums.map((value, index, array) => {
    return array.slice(index).filter(currentValue => currentValue < value).length;
  });
  
  return res;
}