Merge pull request kodecocodes#857 from mdavison/3sum-4sum

[Swift 4.2 Migration] 3Sum and 4Sum

Author: richard-ash

3Sum and 4Sum/3Sum.playground/Contents.swift

@@ -1,3 +1,7 @@
+// last checked with Xcode 10.1
+#if swift(>=4.2)
+print("Hello, Swift 4.2!")
+#endif
 
 extension Collection where Element: Equatable {
 

3Sum and 4Sum/3Sum.playground/playground.xcworkspace/contents.xcworkspacedata

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>IDEDidComputeMac32BitWarning</key>
+	<true/>
+</dict>
+</plist>

3Sum and 4Sum/3Sum.playground/playground.xcworkspace/xcshareddata/IDEWorkspaceChecks.plist

@@ -1,3 +1,8 @@
+// last checked with Xcode 10.1
+#if swift(>=4.2)
+print("Hello, Swift 4.2!")
+#endif
+
 extension Collection where Element: Equatable {
 
   /// In a sorted collection, replaces the given index with a successor mapping to a unique element.

3Sum and 4Sum/4Sum.playground/Contents.swift

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>IDEDidComputeMac32BitWarning</key>
+	<true/>
+</dict>
+</plist>