Merge pull request #530 from remlostime/merge-sort-swift

[Swift 4] Update Merge Sort

Author: kelvinlauKL

Merge Sort/MergeSort.playground/Contents.swift

@@ -1,5 +1,10 @@
 /* Top-down recursive version */
 
+// last checked with Xcode 9.0b4
+#if swift(>=4.0)
+print("Hello, Swift 4!")
+#endif
+
 func mergeSort<T: Comparable>(_ array: [T]) -> [T] {
   guard array.count > 1 else { return array }
   let middleIndex = array.count / 2