quicksort.js

const quicksort = arr => {
  if(arr.length <= 1) return arr;
  const pivotIndex = arr.length / 2;
  const pivot = arr.splice(pivotIndex, 1)[0];
  const left = [];
  const right = [];
  for(var i = 0; i < arr.length; i++){
    if(arr[i] < pivot){
      left.push(arr[i]);
    }else{
      right.push(arr[i]);
    }
  }
  return quicksort(left).concat([ pivot ], quicksort(right));
};

console.log(quicksort([ 22, 35, 27, 11, 9, 48, 16, 99, 2 ]));