Merge pull request kodecocodes#847 from ciccioska/swift-4.2-count-occurences

[Swift 4.2] Count occurrences

Author: richard-ash

Count Occurrences/CountOccurrences.playground/Contents.swift

@@ -1,7 +1,3 @@
-// last checked with Xcode 9.0b4
-#if swift(>=4.0)
-  print("Hello, Swift 4!")
-#endif
 
 func countOccurrencesOfKey(_ key: Int, inArray a: [Int]) -> Int {
   func leftBoundary() -> Int {