Add invert a binary tree.

xspyhack · xspyhack · commit 6fcd572a1a2d · 2016-04-11T16:33:09.000+08:00
diff --git a/Binary Tree/BinaryTree.swift b/Binary Tree/BinaryTree.swift
@@ -53,3 +53,13 @@ extension BinaryTree {
     }
   }
 }
+
+extension BinaryTree {
+  func invert() -> BinaryTree {
+    if case let .Node(left, value, right) = self {
+      return .Node(right.invert(), value, left.invert())
+    } else {
+      return .Empty
+    }
+  }
+}

Original file line number	Diff line number	Diff line change
`@@ -53,3 +53,13 @@ extension BinaryTree {`
`53`	`53`	`}`
`54`	`54`	`}`
`55`	`55`	`}`
	`56`	`+`
	`57`	`+extension BinaryTree {`
	`58`	`+ func invert() -> BinaryTree {`
	`59`	`+ if case let .Node(left, value, right) = self {`
	`60`	`+ return .Node(right.invert(), value, left.invert())`
	`61`	`+ } else {`
	`62`	`+ return .Empty`
	`63`	`+ }`
	`64`	`+ }`
	`65`	`+}`