Merge pull request kodecocodes#824 from JulioBBL/bubble-sort

Add convenience method to Bubble Sort

Author: richard-ash

Bubble Sort/MyPlayground.playground/Contents.swift

@@ -3,4 +3,6 @@ import Foundation
 var array = [4,2,1,3]
 
 print("before:",array)
-print("after:",BubbleSort(array))
+print("after:", bubbleSort(array))
+print("after:", bubbleSort(array, <))
+print("after:", bubbleSort(array, >))

Bubble Sort/MyPlayground.playground/Sources/BubbleSort.swift

@@ -23,14 +23,18 @@ import Foundation
 
 /// Performs the bubble sort algorithm in the array
 ///
-/// - Parameter elements: the array to be sorted
+/// - Parameter elements: a array of elements that implement the Comparable protocol
 /// - Returns: an array with the same elements but in order
-public func BubbleSort<T> (_ elements: [T]) -> [T] where T: Comparable {
+public func bubbleSort<T> (_ elements: [T]) -> [T] where T: Comparable {
+  return bubbleSort(elements, <)
+}
+
+public func bubbleSort<T> (_ elements: [T], _ comparison: (T,T) -> Bool) -> [T]  {
   var array = elements
 
   for i in 0..<array.count {
     for j in 1..<array.count-i {
-      if array[j] < array[j-1] {
+      if comparison(array[j], array[j-1]) {
         let tmp = array[j-1]
         array[j-1] = array[j]
         array[j] = tmp