adds quick sort

Author: kyleshevlin

quickSort/index.js

@@ -0,0 +1,23 @@
+const { printArray } = require('../utils')
+
+function quickSort(array) {
+  printArray(array)
+
+  if (array.length < 2) {
+    return array
+  }
+
+  const pivotIndex = array.length - 1
+  const pivot = array[pivotIndex]
+  const left = []
+  const right = []
+
+  for (let i = 0; i < pivotIndex; i++) {
+    const item = array[i]
+    item < pivot ? left.push(item) : right.push(item)
+  }
+
+  return [...quickSort(left), pivot, ...quickSort(right)]
+}
+
+exports.quickSort = quickSort

quickSort/index.test.js

@@ -0,0 +1,6 @@
+const { quickSort } = require('./index')
+
+test('Quick Sort', () => {
+  const nums = [10, 8, 4, 3, 6, 2, 1, 9, 7, 5]
+  expect(quickSort(nums)).toEqual([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])
+})