Merge pull request #384 from AdrianBinDC/patch-2

Update CountingSort.swift to Swift 3.0 syntax

Author: kelvinlauKL

Counting Sort/CountingSort.swift

@@ -6,39 +6,41 @@
 //  Copyright © 2016 Ali Hafizji. All rights reserved.
 //
 
-enum CountingSortError: ErrorType {
-  case arrayEmpty
+import Foundation
+
+enum CountingSortError: Error {
+    case arrayEmpty
 }
 
 func countingSort(array: [Int]) throws -> [Int] {
-  guard array.count > 0 else {
-    throw CountingSortError.arrayEmpty
-  }
-
-  // Step 1
-  // Create an array to store the count of each element
-  let maxElement = array.maxElement() ?? 0
-
-  var countArray = [Int](count: Int(maxElement + 1), repeatedValue: 0)
-  for element in array {
-    countArray[element] += 1
-  }
-
-  // Step 2
-  // Set each value to be the sum of the previous two values
-  for index in 1 ..< countArray.count {
-    let sum = countArray[index] + countArray[index - 1]
-    countArray[index] = sum
-  }
-
-  print(countArray)
-
-  // Step 3
-  // Place the element in the final array as per the number of elements before it
-  var sortedArray = [Int](count: array.count, repeatedValue: 0)
-  for element in array {
-    countArray[element] -= 1
-    sortedArray[countArray[element]] = element
-  }
-  return sortedArray
+    guard array.count > 0 else {
+        throw CountingSortError.arrayEmpty
+    }
+    
+    // Step 1
+    // Create an array to store the count of each element
+    let maxElement = array.max() ?? 0
+    
+    var countArray = [Int](repeating: 0, count: Int(maxElement + 1))
+    for element in array {
+        countArray[element] += 1
+    }
+    
+    // Step 2
+    // Set each value to be the sum of the previous two values
+    for index in 1 ..< countArray.count {
+        let sum = countArray[index] + countArray[index - 1]
+        countArray[index] = sum
+    }
+    
+    print(countArray)
+    
+    // Step 3
+    // Place the element in the final array as per the number of elements before it
+    var sortedArray = [Int](repeating: 0, count: array.count)
+    for element in array {
+        countArray[element] -= 1
+        sortedArray[countArray[element]] = element
+    }
+    return sortedArray
 }