@@ -822,6 +822,52 @@ function reverse(head) {
 
 ![](https://i.imgur.com/wozvfAe.png)
 
+<div class="codepen" data-height="300" data-theme-id="dark" data-default-tab="js" data-slug-hash="WNjegBp" data-user="roopkt" data-prefill='{"title":"Merge Sort Algorithm","tags":[],"scripts":[],"stylesheets":[]}'>
+<pre data-lang="js">// O(n log(n)) time | O(1) space where n = length of the array.
+function mergeSort(array) {
+const length = array.length;
+if (length &lt; 2) {
+return;
+}
+const mid = length / 2;
+const left = array.slice(0, mid);
+const right = array.slice(mid, length);
+mergeSort(left);
+mergeSort(right);
+stitch(left, right, array);
+}
+
+function stitch(left, right, array) {
+let leftIdx = 0;
+let rightIdx = 0;
+let arrayIdx = 0;
+let leftLength = left.length;
+let rightLength = right.length;
+
+while (leftIdx &lt; leftLength && rightIdx &lt; rightLength) {
+if (left[leftIdx] &lt;= right[rightIdx]) {
+array[arrayIdx] = left[leftIdx];
+leftIdx++;
+} else {
+array[arrayIdx] = right[rightIdx];
+rightIdx++;
+}
+arrayIdx++;
+}
+
+while (leftIdx &lt; leftLength) {
+array[arrayIdx] = left[leftIdx];
+leftIdx++;
+arrayIdx++;
+}
+while (rightIdx &lt; rightLength) {
+array[arrayIdx] = right[rightIdx];
+rightIdx++;
+arrayIdx++;
+}
+}</pre></div>
+
+
 
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