Improve performance for constructors

Sources/SwiftGraph/Union.swift

@@ -37,7 +37,7 @@ public extension UniqueElementsGraph {
 
         // We know vertices in lhs are unique, so we call Graph.addVertex to avoid the uniqueness check of UniqueElementsGraph.addVertex.
         for vertex in firstGraph.vertices {
-            _ = super.addVertex(vertex)
+            _ = addVertex(vertex)
         }
 
         // When vertices are removed from Graph, edges might mutate,

Sources/SwiftGraph/UniqueElementsGraph.swift

@@ -17,15 +17,15 @@
 //  limitations under the License.
 
 /// A subclass of UnweightedGraph that ensures there are no pairs of equal vertices and no repeated edges.
-open class UniqueElementsGraph<V: Equatable>: UnweightedGraph<V> {
+open class UniqueElementsGraph<V: Equatable>: Graph {
+    public var vertices: [V] = [V]()
+    public var edges: [[UnweightedEdge]] = [[UnweightedEdge]]() //adjacency lists
 
-    public override init() {
-        super.init()
+    public init() {
     }
 
     /// Init the Graph with vertices, but removes duplicates. O(n^2)
-    public override init(vertices: [V]) {
-        super.init()
+    public init(vertices: [V]) {
         for vertex in vertices {
             _ = self.addVertex(vertex) // make sure to call our version
         }
@@ -39,13 +39,15 @@ open class UniqueElementsGraph<V: Equatable>: UnweightedGraph<V> {
         if let equalVertexIndex = indexOfVertex(v) {
             return equalVertexIndex
         }
-        return super.addVertex(v)
+        vertices.append(v)
+        edges.append([E]())
+        return vertices.count - 1
     }
 
     /// Only allow the edge to be added once
     ///
     /// - parameter e: The edge to add.
-    public func addEdge(_ e: E) {
+    public func addEdge(_ e: UnweightedEdge) {
         if !edgeExists(from: e.u, to: e.v) {
             edges[e.u].append(e)
         }
@@ -56,7 +58,7 @@ open class UniqueElementsGraph<V: Equatable>: UnweightedGraph<V> {
     /// - parameter from: The starting vertex's index.
     /// - parameter to: The ending vertex's index.
     /// - parameter directed: Is the edge directed? (default `false`)
-    public override func addEdge(fromIndex u: Int, toIndex v: Int, directed: Bool = false) {
+    public func addEdge(fromIndex u: Int, toIndex v: Int, directed: Bool = false) {
         if !edgeExists(from: u, to: v) {
             addEdge(UnweightedEdge(u: u, v: v))
             if !directed && !edgeExists(from: v, to: u) {
@@ -70,9 +72,127 @@ open class UniqueElementsGraph<V: Equatable>: UnweightedGraph<V> {
     /// - parameter from: The starting vertex.
     /// - parameter to: The ending vertex.
     /// - parameter directed: Is the edge directed? (default `false`)
-    public override func addEdge(from: V, to: V, directed: Bool = false) {
+    public func addEdge(from: V, to: V, directed: Bool = false) {
         if let u = indexOfVertex(from), let v = indexOfVertex(to) {
             addEdge(fromIndex: u, toIndex: v, directed: directed)
         }
     }
 }
+
+extension UniqueElementsGraph {
+
+    private func addEdgesForPath(withIndices indices: [Int], directed: Bool) {
+        for i in 0..<indices.count - 1 {
+            addEdge(fromIndex: indices[i], toIndex: indices[i+1], directed: directed)
+        }
+    }
+
+    /// Initialize an UniqueElementsGraph consisting of path.
+    ///
+    /// The resulting graph has the vertices in path and an edge between
+    /// each pair of consecutive vertices in path.
+    ///
+    /// If path is an empty array, the resulting graph is the empty graph.
+    /// If path is an array with a single vertex, the resulting graph has that vertex and no edges.
+    ///
+    /// - Parameters:
+    ///   - path: An array of vertices representing a path.
+    ///   - directed: If false, undirected edges are created.
+    ///               If true, edges are directed from vertex i to vertex i+1 in path.
+    ///               Default is false.
+    public convenience init(withPath path: [V], directed: Bool = false) {
+        self.init(vertices: path)
+
+        guard path.count >= 2 else {
+            if let v = path.first {
+                _ = addVertex(v)
+            }
+            return
+        }
+
+        let indices = path.map({ indexOfVertex($0)! })
+        addEdgesForPath(withIndices: indices, directed: directed)
+    }
+
+    /// Initialize an UniqueElementsGraph consisting of cycle.
+    ///
+    /// The resulting graph has the vertices in cycle and an edge between
+    /// each pair of consecutive vertices in cycle,
+    /// plus an edge between the last and the first vertices.
+    ///
+    /// If path is an empty array, the resulting graph is the empty graph.
+    /// If path is an array with a single vertex, the resulting graph has the vertex
+    /// and a single edge to itself if directed is true.
+    /// If directed is false the resulting graph has the vertex and two edges to itself.
+    ///
+    /// - Parameters:
+    ///   - cycle: An array of vertices representing a cycle.
+    ///   - directed: If false, undirected edges are created.
+    ///               If true, edges are directed from vertex i to vertex i+1 in cycle.
+    ///               Default is false.
+    public convenience init(withCycle cycle: [V], directed: Bool = false) {
+        self.init(vertices: cycle)
+
+        guard cycle.count >= 2 else {
+            if let v = cycle.first {
+                let index = addVertex(v)
+                addEdge(fromIndex: index, toIndex: index)
+            }
+            return
+        }
+
+        let indices = cycle.map({ indexOfVertex($0)! })
+        addEdgesForPath(withIndices: indices, directed: directed)
+        addEdge(fromIndex: indices.last!, toIndex: indices.first!, directed: directed)
+    }
+
+}
+
+extension UniqueElementsGraph where V: Hashable {
+    public convenience init(withPath path: [V], directed: Bool = false) {
+        self.init()
+
+        guard path.count >= 2 else {
+            if let v = path.first {
+                _ = addVertex(v)
+            }
+            return
+        }
+
+        let indices = indicesForPath(path)
+        addEdgesForPath(withIndices: indices, directed: directed)
+    }
+
+
+    public convenience init(withCycle cycle: [V], directed: Bool = false) {
+        self.init()
+
+        guard cycle.count >= 2 else {
+            if let v = cycle.first {
+                let index = addVertex(v)
+                addEdge(fromIndex: index, toIndex: index)
+            }
+            return
+        }
+
+        let indices = indicesForPath(cycle)
+        addEdgesForPath(withIndices: indices, directed: directed)
+        addEdge(fromIndex: indices.last!, toIndex: indices.first!, directed: directed)
+    }
+
+    private func indicesForPath(_ path: [V]) -> [Int] {
+        var indices: [Int] = []
+        var indexForVertex: Dictionary<V, Int> = [:]
+
+        for v in path {
+            if let index = indexForVertex[v] {
+                indices.append(index)
+            } else {
+                let index = addVertex(v)
+                indices.append(index)
+                indexForVertex[v] = index
+            }
+        }
+        return indices
+    }
+}

Sources/SwiftGraph/UnweightedGraph.swift

@@ -51,8 +51,7 @@ open class UnweightedGraph<V: Equatable>: Graph {
         }
 
         for i in 0..<path.count - 1 {
-            let vertices = path[i...i+1]
-            self.addEdge(from: vertices.first!, to: vertices.last!, directed: directed)
+            self.addEdge(fromIndex: i, toIndex: i+1, directed: directed)
         }
     }
 
@@ -75,7 +74,7 @@ open class UnweightedGraph<V: Equatable>: Graph {
     public convenience init(withCycle cycle: [V], directed: Bool = false) {
         self.init(withPath: cycle, directed: directed)
         if cycle.count > 0 {
-            self.addEdge(from: cycle.last!, to: cycle.first!, directed: directed)
+            self.addEdge(fromIndex: cycle.count-1, toIndex: 0, directed: directed)
         }
     }
 

SwiftGraph.xcodeproj/project.pbxproj

@@ -36,7 +36,7 @@
 		7985B92B1E5A503200C100E7 /* Queue.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5589B47A1C0E75A700D6664E /* Queue.swift */; };
 		B5100A4D208B97AA00C7A73A /* UnweightedGraphTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = B5100A4B208B97A800C7A73A /* UnweightedGraphTests.swift */; };
 		B51B460B2083E14200CD0463 /* Union.swift in Sources */ = {isa = PBXBuildFile; fileRef = B51B460A2083E14200CD0463 /* Union.swift */; };
-		B523F2EA2094F0E2006587ED /* UniqueElementsGraphInitTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = B523F2E92094F0E2006587ED /* UniqueElementsGraphInitTests.swift */; };
+		B523F2EA2094F0E2006587ED /* UniqueElementsGraphHashableInitTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = B523F2E92094F0E2006587ED /* UniqueElementsGraphHashableInitTests.swift */; };
 		B52ABD39208955BD00FBF10C /* UnionTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = B52ABD37208955B500FBF10C /* UnionTests.swift */; };
 		B54FDA6E21729EFF00057C51 /* Constructors.swift in Sources */ = {isa = PBXBuildFile; fileRef = B54FDA6D21729EFF00057C51 /* Constructors.swift */; };
 		B54FDA712172A34D00057C51 /* ConstructorsTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = B54FDA702172A34D00057C51 /* ConstructorsTests.swift */; };
@@ -45,6 +45,9 @@
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 		B5EACB1D2172315E00E527BD /* SwiftGraph.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 7985B8FB1E5A4FB800C100E7 /* SwiftGraph.framework */; };
 		B5EACB292172336900E527BD /* SearchPerformanceTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = B5DD6DA42171EEE1007EFF44 /* SearchPerformanceTests.swift */; };
+		B5EF143121791009008FCC5C /* UniqueElementsGraphInitTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = B5EF143021791009008FCC5C /* UniqueElementsGraphInitTests.swift */; };
+		B5EF143321791348008FCC5C /* UniqueElementsGraphHashableTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = B5EF143221791348008FCC5C /* UniqueElementsGraphHashableTests.swift */; };
+		B5EF1437217913F1008FCC5C /* EquatableTypes.swift in Sources */ = {isa = PBXBuildFile; fileRef = B5EF1436217913F1008FCC5C /* EquatableTypes.swift */; };
 /* End PBXBuildFile section */
 
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@@ -118,7 +121,7 @@
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 		B5100A4B208B97A800C7A73A /* UnweightedGraphTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UnweightedGraphTests.swift; sourceTree = "<group>"; };
 		B51B460A2083E14200CD0463 /* Union.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; name = Union.swift; path = ../Sources/SwiftGraph/Union.swift; sourceTree = "<group>"; };
-		B523F2E92094F0E2006587ED /* UniqueElementsGraphInitTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = UniqueElementsGraphInitTests.swift; sourceTree = "<group>"; };
+		B523F2E92094F0E2006587ED /* UniqueElementsGraphHashableInitTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = UniqueElementsGraphHashableInitTests.swift; sourceTree = "<group>"; };
 		B52ABD37208955B500FBF10C /* UnionTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = UnionTests.swift; sourceTree = "<group>"; };
 		B54FDA6D21729EFF00057C51 /* Constructors.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; name = Constructors.swift; path = ../Sources/SwiftGraph/Constructors.swift; sourceTree = "<group>"; };
 		B54FDA702172A34D00057C51 /* ConstructorsTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ConstructorsTests.swift; sourceTree = "<group>"; };
@@ -127,6 +130,9 @@
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 		B5DD6DA42171EEE1007EFF44 /* SearchPerformanceTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SearchPerformanceTests.swift; sourceTree = "<group>"; };
 		B5EACB222172315E00E527BD /* SwiftGraphPerformanceTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = SwiftGraphPerformanceTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
+		B5EF143021791009008FCC5C /* UniqueElementsGraphInitTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = UniqueElementsGraphInitTests.swift; sourceTree = "<group>"; };
+		B5EF143221791348008FCC5C /* UniqueElementsGraphHashableTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = UniqueElementsGraphHashableTests.swift; sourceTree = "<group>"; };
+		B5EF1436217913F1008FCC5C /* EquatableTypes.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = EquatableTypes.swift; sourceTree = "<group>"; };
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@@ -260,6 +266,7 @@
 		7985B9091E5A4FB900C100E7 /* SwiftGraphTests */ = {
 			isa = PBXGroup;
 			children = (
+				B5EF1435217913E0008FCC5C /* Utils */,
 				B54FDA6F2172A30600057C51 /* Constructors */,
 				B523F2E82094F0A1006587ED /* UniqueElementsGraph */,
 				557F55E91F8AB247002AF0BF /* Info.plist */,
@@ -281,7 +288,9 @@
 			isa = PBXGroup;
 			children = (
 				B5D229BD207BF36900151820 /* UniqueElementsGraphTests.swift */,
-				B523F2E92094F0E2006587ED /* UniqueElementsGraphInitTests.swift */,
+				B5EF143221791348008FCC5C /* UniqueElementsGraphHashableTests.swift */,
+				B5EF143021791009008FCC5C /* UniqueElementsGraphInitTests.swift */,
+				B523F2E92094F0E2006587ED /* UniqueElementsGraphHashableInitTests.swift */,
 			);
 			path = UniqueElementsGraph;
 			sourceTree = "<group>";
@@ -312,6 +321,14 @@
 			path = Tests/SwiftGraphPerformanceTests;
 			sourceTree = "<group>";
 		};
+		B5EF1435217913E0008FCC5C /* Utils */ = {
+			isa = PBXGroup;
+			children = (
+				B5EF1436217913F1008FCC5C /* EquatableTypes.swift */,
+			);
+			path = Utils;
+			sourceTree = "<group>";
+		};
 /* End PBXGroup section */
 
 /* Begin PBXHeadersBuildPhase section */
@@ -522,10 +539,13 @@
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 				55E784281ED2971E003899D0 /* MSTTests.swift in Sources */,
 				B5100A4D208B97AA00C7A73A /* UnweightedGraphTests.swift in Sources */,
+				B5EF1437217913F1008FCC5C /* EquatableTypes.swift in Sources */,
 				7985B91D1E5A4FCB00C100E7 /* DijkstraGraphTests.swift in Sources */,
 				7985B91F1E5A4FCB00C100E7 /* SwiftGraphSortTests.swift in Sources */,
+				B5EF143321791348008FCC5C /* UniqueElementsGraphHashableTests.swift in Sources */,
 				55F5EA5B2151E33100DFC301 /* SwiftGraphCodableTests.swift in Sources */,
-				B523F2EA2094F0E2006587ED /* UniqueElementsGraphInitTests.swift in Sources */,
+				B523F2EA2094F0E2006587ED /* UniqueElementsGraphHashableInitTests.swift in Sources */,
+				B5EF143121791009008FCC5C /* UniqueElementsGraphInitTests.swift in Sources */,
 				B54FDA712172A34D00057C51 /* ConstructorsTests.swift in Sources */,
 				B5D229BF207BF3A800151820 /* UniqueElementsGraphTests.swift in Sources */,
 			);