Fixed playgrounds for Swift 3.

Author: Kelvin Lau

Depth-First Search/DepthFirstSearch.playground/Pages/Simple Example.xcplaygroundpage/Contents.swift

@@ -1,10 +1,12 @@
+
+
 func depthFirstSearch(graph: Graph, source: Node) -> [String] {
   var nodesExplored = [source.label]
   source.visited = true
 
   for edge in source.neighbors {
     if !edge.neighbor.visited {
-      nodesExplored += depthFirstSearch(graph, source: edge.neighbor)
+      nodesExplored += depthFirstSearch(graph: graph, source: edge.neighbor)
     }
   }
   return nodesExplored
@@ -14,24 +16,24 @@ func depthFirstSearch(graph: Graph, source: Node) -> [String] {
 
 let graph = Graph()
 
-let nodeA = graph.addNode("a")
-let nodeB = graph.addNode("b")
-let nodeC = graph.addNode("c")
-let nodeD = graph.addNode("d")
-let nodeE = graph.addNode("e")
-let nodeF = graph.addNode("f")
-let nodeG = graph.addNode("g")
-let nodeH = graph.addNode("h")
-
-graph.addEdge(nodeA, neighbor: nodeB)
-graph.addEdge(nodeA, neighbor: nodeC)
-graph.addEdge(nodeB, neighbor: nodeD)
-graph.addEdge(nodeB, neighbor: nodeE)
-graph.addEdge(nodeC, neighbor: nodeF)
-graph.addEdge(nodeC, neighbor: nodeG)
-graph.addEdge(nodeE, neighbor: nodeH)
-graph.addEdge(nodeE, neighbor: nodeF)
-graph.addEdge(nodeF, neighbor: nodeG)
-
-let nodesExplored = depthFirstSearch(graph, source: nodeA)
+let nodeA = graph.addNode(label: "a")
+let nodeB = graph.addNode(label: "b")
+let nodeC = graph.addNode(label: "c")
+let nodeD = graph.addNode(label: "d")
+let nodeE = graph.addNode(label: "e")
+let nodeF = graph.addNode(label: "f")
+let nodeG = graph.addNode(label: "g")
+let nodeH = graph.addNode(label: "h")
+
+graph.addEdge(source: nodeA, neighbor: nodeB)
+graph.addEdge(source: nodeA, neighbor: nodeC)
+graph.addEdge(source: nodeB, neighbor: nodeD)
+graph.addEdge(source: nodeB, neighbor: nodeE)
+graph.addEdge(source: nodeC, neighbor: nodeF)
+graph.addEdge(source: nodeC, neighbor: nodeG)
+graph.addEdge(source: nodeE, neighbor: nodeH)
+graph.addEdge(source: nodeE, neighbor: nodeF)
+graph.addEdge(source: nodeF, neighbor: nodeG)
+
+let nodesExplored = depthFirstSearch(graph: graph, source: nodeA)
 print(nodesExplored)

Depth-First Search/DepthFirstSearch.playground/Pages/Simple Example.xcplaygroundpage/timeline.xctimeline

@@ -5,7 +5,7 @@ public class Graph: CustomStringConvertible, Equatable {
     self.nodes = []
   }
 
-  public func addNode(label: String) -> Node {
+  @discardableResult public func addNode(label: String) -> Node {
     let node = Node(label: label)
     nodes.append(node)
     return node
@@ -35,14 +35,14 @@ public class Graph: CustomStringConvertible, Equatable {
     let duplicated = Graph()
 
     for node in nodes {
-      duplicated.addNode(node.label)
+      duplicated.addNode(label: node.label)
     }
 
     for node in nodes {
       for edge in node.neighbors {
-        let source = duplicated.findNodeWithLabel(node.label)
-        let neighbour = duplicated.findNodeWithLabel(edge.neighbor.label)
-        duplicated.addEdge(source, neighbor: neighbour)
+        let source = duplicated.findNodeWithLabel(label: node.label)
+        let neighbour = duplicated.findNodeWithLabel(label: edge.neighbor.label)
+        duplicated.addEdge(source: source, neighbor: neighbour)
       }
     }
 

Depth-First Search/DepthFirstSearch.playground/Sources/Graph.swift

@@ -1,3 +1,4 @@
+
 public class Node: CustomStringConvertible, Equatable {
   public var neighbors: [Edge]
 
@@ -23,7 +24,7 @@ public class Node: CustomStringConvertible, Equatable {
   }
 
   public func remove(edge: Edge) {
-    neighbors.removeAtIndex(neighbors.indexOf { $0 === edge }!)
+    neighbors.remove(at: neighbors.index { $0 === edge }!)
   }
 }