Merge pull request #545 from marsonya/doctests/cocktail-shaker-sort

Improved CocktailShakerSort and added Doctests

Author: marsonya

Sorts/CocktailShakerSort.js

@@ -1,40 +1,55 @@
 /*
- * Cocktail shaker sort is a sort algorithm that is a bidirectional bubble sort
- * more information: https://en.wikipedia.org/wiki/Cocktail_shaker_sort
- * more information: https://en.wikipedia.org/wiki/Bubble_sort
+ * Cocktail Shaker Sort is an algorithm that is a Bidirectional Bubble Sort.
+ * The algorithm extends bubble sort by operating in two directions.
+ * While it improves on bubble sort by more quickly moving items to the beginning of the list,
+ * it provides only marginal performance improvements.
  *
+ * Wikipedia (Cocktail Shaker Sort): https://en.wikipedia.org/wiki/Cocktail_shaker_sort
+ * Wikipedia (Bubble Sort): https://en.wikipedia.org/wiki/Bubble_sort
+ *
+ */
+
+/**
+ * Doctests
+ *
+ * > cocktailShakerSort([5, 4, 1, 2, 3])
+ * [1, 2, 3, 4, 5]
+ * > cocktailShakerSort([])
+ * []
+ * > cocktailShakerSort([1, 2, 3])
+ * [1, 2, 3]
  */
+
 function cocktailShakerSort (items) {
   for (let i = items.length - 1; i > 0; i--) {
-    let swapped = false
     let j
 
-    // backwards
+    // Backwards
     for (j = items.length - 1; j > i; j--) {
       if (items[j] < items[j - 1]) {
         [items[j], items[j - 1]] = [items[j - 1], items[j]]
-        swapped = true
       }
     }
 
-    // forwards
+    // Forwards
     for (j = 0; j < i; j++) {
       if (items[j] > items[j + 1]) {
         [items[j], items[j + 1]] = [items[j + 1], items[j]]
-        swapped = true
       }
     }
-    if (!swapped) {
-      return
-    }
   }
-}
 
-// Implementation of cocktailShakerSort
+  return items
+}
 
-var ar = [5, 6, 7, 8, 1, 2, 12, 14]
-// Array before Sort
-console.log(ar)
-cocktailShakerSort(ar)
-// Array after sort
-console.log(ar)
+/**
+* Implementation of Cocktail Shaker Sort
+*/
+const array = [5, 6, 7, 8, 1, 2, 12, 14]
+// Before Sort
+console.log('\n- Before Sort | Implementation of Cocktail Shaker Sort -')
+console.log(array)
+// After Sort
+console.log('- After Sort | Implementation of Cocktail Shaker Sort -')
+console.log(cocktailShakerSort(array))
+console.log('\n')