Add CountingSort in Javscript

Author: kelvins

README.md

@@ -2943,8 +2943,8 @@ In order to achieve greater coverage and encourage more people to contribute to
   </a>
   </td>
   <td> <!-- JavaScript -->
-  <a href="./CONTRIBUTING.md">
-  <img align="center" height="25" src="./logos/github.svg" />
+  <a href="./src/javascript/CountingSort.js">
+  <img align="center" height="25" src="./logos/javascript.svg" />
   </a>
   </td>
   <td> <!-- Swift -->

src/javascript/CountingSort.js

@@ -0,0 +1,31 @@
+function countingSort(arr) {
+ // Find the maximum element in the array to determine the range
+ let max = Math.max(...arr);
+
+ // Create a count array to store the count of each element
+ let count = new Array(max + 1).fill(0);
+
+ // Count the occurrences of each element in the input array
+ for (let i = 0; i < arr.length; i++) {
+ count[arr[i]]++;
+ }
+
+ // Modify the count array to store the actual position of each element
+ for (let i = 1; i <= max; i++) {
+ count[i] += count[i - 1];
+ }
+
+ // Create a new output array and store the elements in their sorted order
+ let output = new Array(arr.length);
+ for (let i = arr.length - 1; i >= 0; i--) {
+ output[count[arr[i]] - 1] = arr[i];
+ count[arr[i]]--;
+ }
+
+ return output;
+}
+
+const arr = [4, 2, 2, 8, 3, 3, 1];
+const sortedArr = countingSort(arr);
+console.log("Original array:", arr);
+console.log("Sorted array:", sortedArr);