Added Shell Sort [Javascript] (iiitv#312)

* Added Shell Sort [Javascript]

* Added Shell Sort [Javascript]

* Auto stash before rebase of "origin/master"
Fix spaces

* Added param comment

* Renamed

* Fixed temp declaration

README.md

@@ -37,7 +37,7 @@ Community (college) maintained list of Algorithms and Data Structures implementa
 | [Quick Select](https://en.wikipedia.org/wiki/Quickselect) | [:white_check_mark:](quick_select/quick_select.c) | | [:white_check_mark:](quick_select/QuickSelect.java) | [:white_check_mark:](quick_select/quick_select.py) | | |
 | [Quicksort](https://en.wikipedia.org/wiki/Quicksort) | [:white_check_mark:](quicksort/quicksort.c) | | [:white_check_mark:](quicksort/QuickSort.java) | [:white_check_mark:](quicksort/quick_sort.py) | [:white_check_mark:](quicksort/quick_sort.go) | |
 | [Rod Cutting Problem](http://www.geeksforgeeks.org/dynamic-programming-set-13-cutting-a-rod/) | [:white_check_mark:](rod_cutting_problem/rod_cutting.c) | | [:white_check_mark:](rod_cutting_problem/RodCutting.java) | [:white_check_mark:](rod_cutting_problem/rod_cutting.py) | [:white_check_mark:](rod_cutting_problem/rod_cutting.go) | |
-| [Shell Sort](https://en.wikipedia.org/wiki/Shellsort) | | [:white_check_mark:](shell_sort/ShellSort.cpp) | | [:white_check_mark:](/shell_sort/shell_sort.py) | [:white_check_mark:](shell_sort/shell_sort.go) | |
+| [Shell Sort](https://en.wikipedia.org/wiki/Shellsort) | | [:white_check_mark:](shell_sort/ShellSort.cpp) | | [:white_check_mark:](/shell_sort/shell_sort.py) | [:white_check_mark:](shell_sort/shell_sort.go) | [:white_check_mark:](shell_sort/shellSort.js) |
 | [Sieve of Eratosthenes](https://en.wikipedia.org/wiki/Sieve_of_Eratosthenes) | [:white_check_mark:](sieve_of_eratosthenes/sieveOfEratosthenes.c) | | [:white_check_mark:](sieve_of_eratosthenes/SieveOfEratosthenes.java) | [:white_check_mark:](sieve_of_eratosthenes/sieve_of_eratosthenes.py) | [:white_check_mark:](sieve_of_eratosthenes/sieve_of_eratosthenes.go) | |
 | [Sleep Sort](http://www.geeksforgeeks.org/sleep-sort-king-laziness-sorting-sleeping/) | | | | [:white_check_mark:](sleep_sort/sleep_sort.py) | | |
 

shell_sort/shellSort.js

@@ -0,0 +1,30 @@
+/*
+ * Worst case time complexity = O(n^2)
+ * Best case complexity = O(nlog(n))
+ * @param {Array} data
+ * returns sorted data
+ */
+function shellSort (data) {
+	let temp;
+	for (let i = Math.floor(data.length / 2); i > 0; i = Math.floor(i / 2)) {
+		for (let j = i; j < data.length; j++) {
+			for (let k = j - i; k >= 0; k -= i) {
+				if (data[k + i] >= data[k]) {
+					break;
+				} else {
+					temp = data[k];
+					data[k] = data[k + i];
+					data[k + i] = temp;
+				}
+			}
+		}
+	}
+	return data;
+}
+
+function main () {
+	let data = [1000, 45, -45, 121, 47, 45, 65, 121, -1, 103, 45, 34];
+	console.log(shellSort(data));
+}
+
+main();