function quickSort (inputArr) {
  function swap (arr, a, b) {
    [arr[a], arr[b]] = [arr[b], arr[a]]
  }

  function partition (arr, left, right) {
    let partitionPoint = left
    const pivot = arr[right]
    for (let i = left; i < right; i++) {
      if (arr[i] < pivot) {
        swap(arr, i, partitionPoint)
        partitionPoint++
      }
    }
    swap(arr, partitionPoint, right)

    return partitionPoint
  }

  function sort (arr, left, right) {
    if (left > right) return
    const boundary = partition(arr, left, right)
    sort(arr, left, boundary - 1)
    sort(arr, boundary + 1, right)
  }
  sort(inputArr, 0, inputArr.length - 1)
  return inputArr
}