<pre class="shiki github-dark shaku"><code>/** * @param {number[]} arr */function quickSort(arr, start, end) { const pivot = end || arr.length - 1 let pointer = start || 0 if (start &gt;= end || arr.length &lt;= 1) return; // only one item, array is sorted already for (let i = pointer; i &lt; pivot; i++) { if (arr[i] &lt;= arr[pivot]) { if (i !== pointer) { [arr[i], arr[pointer]] = [arr[pointer], arr[i]] } pointer++; } } // put pointer beetwen sorted parts [arr[pivot], arr[pointer]] = [arr[pointer], arr[pivot]] // recursive case quickSort(arr, 0, pointer - 1) quickSort(arr, pointer + 1, pivot)}</code></pre>

Simple in-place solution with Lomuto partition scheme. Worst case O(n^2), average O( n log n)

Even for Front-End Engineer, it is a must to understand how basic sorting algorithms work. Now you are asked to implement Quick Sort, which sorts an i…