Exercise: Quicksort (Partition)

quickSort.js

function quickSort(arr) {
  if (arr.length === 0) return [];
  const pivot = arr[0];
  const left  = arr.filter((num, i) => i !== 0 && num < pivot);
  const equal = arr.filter(num => num === pivot);
  const right = arr.filter((num, i) => i !== 0 && num > pivot);
  return [...left, ...equal, ...right];
}