Example #1
0
        public void CheckIfDFSIsCorrect()
        {
            var vertices = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };

            var graph = new DirectedALGraph <int>();

            graph.AddVertices(vertices);

            // Graph is:
            // 1 -> 3, 4
            // 1 <- 2
            // 2 -> 1, 5
            // 2 <- 3, 5, 6
            // 3 -> 2, 6
            // 3 <- 1, 4
            // 4 -> 3, 6
            // 4 <- 1, 7
            // 5 -> 2, 7, 8
            // 5 <- 2, 8
            // 6 -> 2
            // 6 <- 3, 4
            // 7 -> 4
            // 7 <- 5, 8
            // 8 -> 5, 7
            // 8 <- 5
            // 9 ->
            // 9 <-
            graph.AddEdge(1, 3);
            graph.AddEdge(1, 4);
            graph.AddEdge(2, 1);
            graph.AddEdge(2, 5);
            graph.AddEdge(3, 2);
            graph.AddEdge(3, 6);
            graph.AddEdge(4, 3);
            graph.AddEdge(4, 6);
            graph.AddEdge(5, 2);
            graph.AddEdge(5, 7);
            graph.AddEdge(5, 8);
            graph.AddEdge(6, 2);
            graph.AddEdge(7, 4);
            graph.AddEdge(8, 5);
            graph.AddEdge(8, 7);

            // Expected dfs for vertex 1:
            // 1 | 3 | 2 | 5 | 7 | 4 | 6 | 8
            var dfsExpectedOutput = new int[] { 1, 3, 2, 5, 7, 4, 6, 8 };
            var dfs = graph.DepthFirstSearch(1).ToList();

            Assert.IsTrue(dfs.Count == dfsExpectedOutput.Length);
            for (int i = 0; i < dfs.Count; i++)
            {
                Assert.IsTrue(dfs[i] == dfsExpectedOutput[i]);
            }

            // Expected dfs edges for vertex 1:
            // 1 | 3 | 2 | 5 | 7 | 4 | 5
            // 3 | 2 | 5 | 7 | 4 | 6 | 8
            var dfsExpectedSources      = new int[] { 1, 3, 2, 5, 7, 4, 5 };
            var dfsExpectedDestinations = new int[] { 3, 2, 5, 7, 4, 6, 8 };
            var dfsEdges = graph.DepthFirstSearchEdges(1).ToList();

            Assert.IsTrue(dfsEdges.Count == dfsExpectedSources.Length);
            for (int i = 0; i < dfsEdges.Count; i++)
            {
                Assert.IsTrue(dfsEdges[i].Source == dfsExpectedSources[i]);
                Assert.IsTrue(dfsEdges[i].Destination == dfsExpectedDestinations[i]);
            }

            // Expected dfs for vertex 8:
            // 8 | 5 | 2 | 1 | 3 | 6 | 4 | 7
            dfsExpectedOutput = new int[] { 8, 5, 2, 1, 3, 6, 4, 7 };
            dfs = graph.DepthFirstSearch(8).ToList();

            Assert.IsTrue(dfs.Count == dfsExpectedOutput.Length);
            for (int i = 0; i < dfs.Count; i++)
            {
                Assert.IsTrue(dfs[i] == dfsExpectedOutput[i]);
            }

            // Expected dfs edges for vertex 8:
            // 8 | 5 | 2 | 1 | 3 | 1 | 5
            // 5 | 2 | 1 | 3 | 6 | 4 | 7
            dfsExpectedSources      = new int[] { 8, 5, 2, 1, 3, 1, 5 };
            dfsExpectedDestinations = new int[] { 5, 2, 1, 3, 6, 4, 7 };
            dfsEdges = graph.DepthFirstSearchEdges(8).ToList();

            Assert.IsTrue(dfsEdges.Count == dfsExpectedSources.Length);
            for (int i = 0; i < dfsEdges.Count; i++)
            {
                Assert.IsTrue(dfsEdges[i].Source == dfsExpectedSources[i]);
                Assert.IsTrue(dfsEdges[i].Destination == dfsExpectedDestinations[i]);
            }
        }
        public void DirectedAndUnweightedGraphShortestsPathsCheck()
        {
            var vertices = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };

            var graph = new DirectedALGraph <int>();

            graph.AddVertices(vertices);

            // Graph is:
            // 1 -> 3, 4
            // 1 <- 2
            // 2 -> 1, 5
            // 2 <- 3, 5, 6
            // 3 -> 2, 6
            // 3 <- 1, 4
            // 4 -> 3, 6
            // 4 <- 1, 7
            // 5 -> 2, 7, 8
            // 5 <- 2, 8
            // 6 -> 2
            // 6 <- 3, 4
            // 7 -> 4
            // 7 <- 5, 8
            // 8 -> 5, 7
            // 8 <- 5
            // 9 ->
            // 9 <-
            graph.AddEdge(1, 3);
            graph.AddEdge(1, 4);
            graph.AddEdge(2, 1);
            graph.AddEdge(2, 5);
            graph.AddEdge(3, 2);
            graph.AddEdge(3, 6);
            graph.AddEdge(4, 3);
            graph.AddEdge(4, 6);
            graph.AddEdge(5, 2);
            graph.AddEdge(5, 7);
            graph.AddEdge(5, 8);
            graph.AddEdge(6, 2);
            graph.AddEdge(7, 4);
            graph.AddEdge(8, 5);
            graph.AddEdge(8, 7);

            // Expected shortest paths for vertex 1
            // 1 to 2 : 1 -> 3 -> 2
            // 1 to 3 : 1 -> 3
            // 1 to 4 : 1 -> 4
            // 1 to 5 : 1 -> 3 -> 2 -> 5
            // 1 to 6 : 1 -> 3 -> 6
            // 1 to 7 : 1 -> 3 -> 2 -> 5 -> 7
            // 1 to 8 : 1 -> 3 -> 2 -> 5 -> 8
            // 1 to 9 : no path
            var expectedPaths = new int[7][]
            {
                new int[] { 1, 3, 2 },
                new int[] { 1, 3 },
                new int[] { 1, 4 },
                new int[] { 1, 3, 2, 5 },
                new int[] { 1, 3, 6 },
                new int[] { 1, 3, 2, 5, 7 },
                new int[] { 1, 3, 2, 5, 8 }
            };

            var paths = graph.DijkstraShortestPaths(1);

            for (int i = 0; i < 7; i++)
            {
                var curPath = paths.VerticesPathTo(i + 2);

                for (int j = 0; j < curPath.Count; j++)
                {
                    if (expectedPaths[i][j] != curPath[j])
                    {
                        Assert.Fail();
                    }
                }
            }
            Assert.IsFalse(paths.HasPathTo(9));

            // Expected shortest paths for vertex 8
            // 8 to 1 : 8 -> 5 -> 2 -> 1
            // 8 to 2 : 8 -> 5 -> 2
            // 8 to 3 : 8 -> 7 -> 4 -> 3
            // 8 to 4 : 8 -> 7 -> 4
            // 8 to 5 : 8 -> 5
            // 8 to 6 : 8 -> 7 -> 4 -> 6
            // 8 to 7 : 8 -> 7
            // 8 to 9 : no path
            expectedPaths = new int[7][]
            {
                new int[] { 8, 5, 2, 1 },
                new int[] { 8, 5, 2 },
                new int[] { 8, 7, 4, 3 },
                new int[] { 8, 7, 4 },
                new int[] { 8, 5 },
                new int[] { 8, 7, 4, 6 },
                new int[] { 8, 7 }
            };

            paths = graph.DijkstraShortestPaths(8);

            for (int i = 0; i < 7; i++)
            {
                var curPath = paths.VerticesPathTo(i + 1);

                for (int j = 0; j < curPath.Count; j++)
                {
                    if (expectedPaths[i][j] != curPath[j])
                    {
                        Assert.Fail();
                    }
                }
            }
            Assert.IsFalse(paths.HasPathTo(9));
        }
Example #3
0
        public void CheckIfBFSIsCorrect()
        {
            var vertices = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };

            var graph = new DirectedALGraph <int>();

            graph.AddVertices(vertices);

            // Graph is:
            // 1 -> 3, 4
            // 1 <- 2
            // 2 -> 1, 5
            // 2 <- 3, 5, 6
            // 3 -> 2, 6
            // 3 <- 1, 4
            // 4 -> 3, 6
            // 4 <- 1, 7
            // 5 -> 2, 7, 8
            // 5 <- 2, 8
            // 6 -> 2
            // 6 <- 3, 4
            // 7 -> 4
            // 7 <- 5, 8
            // 8 -> 5, 7
            // 8 <- 5
            // 9 ->
            // 9 <-
            graph.AddEdge(1, 3);
            graph.AddEdge(1, 4);
            graph.AddEdge(2, 1);
            graph.AddEdge(2, 5);
            graph.AddEdge(3, 2);
            graph.AddEdge(3, 6);
            graph.AddEdge(4, 3);
            graph.AddEdge(4, 6);
            graph.AddEdge(5, 2);
            graph.AddEdge(5, 7);
            graph.AddEdge(5, 8);
            graph.AddEdge(6, 2);
            graph.AddEdge(7, 4);
            graph.AddEdge(8, 5);
            graph.AddEdge(8, 7);

            // Expected bfs for vertex 1:
            // 1 | 3 4 | 2 6 | 5 | 7 8
            var bfsExpectedOutput = new int[] { 1, 3, 4, 2, 6, 5, 7, 8 };
            var bfs = graph.BreadthFirstSearch(1).ToList();

            Assert.IsTrue(bfs.Count == bfsExpectedOutput.Length);
            for (int i = 0; i < bfs.Count; i++)
            {
                Assert.IsTrue(bfs[i] == bfsExpectedOutput[i]);
            }

            // Expected bfs edges for vertex 1:
            // 1 1 | 3 3 | 2 | 5 5
            // 3 4 | 2 6 | 5 | 7 8
            var bfsExpectedSources      = new int[] { 1, 1, 3, 3, 2, 5, 5 };
            var bfsExpectedDestinations = new int[] { 3, 4, 2, 6, 5, 7, 8 };
            var bfsEdges = graph.BreadthFirstSearchEdges(1).ToList();

            Assert.IsTrue(bfsEdges.Count == bfsExpectedSources.Length);
            for (int i = 0; i < bfsEdges.Count; i++)
            {
                Assert.IsTrue(bfsEdges[i].Source == bfsExpectedSources[i]);
                Assert.IsTrue(bfsEdges[i].Destination == bfsExpectedDestinations[i]);
            }

            // Expected bfs for vertex 8:
            // 8 | 5 7 | 2 | 4 | 1 | 3 6
            bfsExpectedOutput = new int[] { 8, 5, 7, 2, 4, 1, 3, 6 };
            bfs = graph.BreadthFirstSearch(8).ToList();

            Assert.IsTrue(bfs.Count == bfsExpectedOutput.Length);
            for (int i = 0; i < bfs.Count; i++)
            {
                Assert.IsTrue(bfs[i] == bfsExpectedOutput[i]);
            }

            // Expected bfs edges for vertex 8:
            // 8 8 | 5 | 7 | 2 | 4 4
            // 5 7 | 2 | 4 | 1 | 3 6
            bfsExpectedSources      = new int[] { 8, 8, 5, 7, 2, 4, 4 };
            bfsExpectedDestinations = new int[] { 5, 7, 2, 4, 1, 3, 6 };
            bfsEdges = graph.BreadthFirstSearchEdges(8).ToList();

            Assert.IsTrue(bfsEdges.Count == bfsExpectedSources.Length);
            for (int i = 0; i < bfsEdges.Count; i++)
            {
                Assert.IsTrue(bfsEdges[i].Source == bfsExpectedSources[i]);
                Assert.IsTrue(bfsEdges[i].Destination == bfsExpectedDestinations[i]);
            }
        }
Example #4
0
        public void CheckIfOutgoingEdgesAreCorrect()
        {
            var vertices = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };

            var graph = new DirectedALGraph <int>();

            graph.AddVertices(vertices);

            // Graph is:
            // 1 -> 3, 4
            // 1 <- 2
            // 2 -> 1, 5
            // 2 <- 3, 5, 6
            // 3 -> 2, 6
            // 3 <- 1, 4
            // 4 -> 3, 6
            // 4 <- 1, 7
            // 5 -> 2, 7, 8
            // 5 <- 2, 8
            // 6 -> 2
            // 6 <- 3, 4
            // 7 -> 4
            // 7 <- 5, 8
            // 8 -> 5, 7
            // 8 <- 5
            // 9 ->
            // 9 <-
            graph.AddEdge(1, 3);
            graph.AddEdge(1, 4);
            graph.AddEdge(2, 1);
            graph.AddEdge(2, 5);
            graph.AddEdge(3, 2);
            graph.AddEdge(3, 6);
            graph.AddEdge(4, 3);
            graph.AddEdge(4, 6);
            graph.AddEdge(5, 2);
            graph.AddEdge(5, 7);
            graph.AddEdge(5, 8);
            graph.AddEdge(6, 2);
            graph.AddEdge(7, 4);
            graph.AddEdge(8, 5);
            graph.AddEdge(8, 7);

            // Vertex 1 expected outgoing edges: 3 4
            var expected = new int[] { 3, 4 };
            var edges    = graph.OutgoingEdgesSorted(1).ToList();

            Assert.IsTrue(edges.Count == expected.Length);
            for (int i = 0; i < expected.Length; i++)
            {
                Assert.IsTrue(edges[i].Destination == expected[i]);
            }

            // Vertex 5 expected outgoing edges: 2 7 8
            expected = new int[] { 2, 7, 8 };
            edges    = graph.OutgoingEdgesSorted(5).ToList();
            Assert.IsTrue(edges.Count == expected.Length);
            for (int i = 0; i < expected.Length; i++)
            {
                Assert.IsTrue(edges[i].Destination == expected[i]);
            }

            // Vertex 7 expected outgoing edges: 4
            expected = new int[] { 4 };
            edges    = graph.OutgoingEdgesSorted(7).ToList();
            Assert.IsTrue(edges.Count == expected.Length);
            for (int i = 0; i < expected.Length; i++)
            {
                Assert.IsTrue(edges[i].Destination == expected[i]);
            }
        }
Example #5
0
        public void RemovingVerticesAndCheckingIfRemovedProperly()
        {
            var vertices = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };

            var graph = new DirectedALGraph <int>();

            graph.AddVertices(vertices);

            // Graph is:
            // 1 -> 3, 4
            // 1 <- 2
            // 2 -> 1, 5
            // 2 <- 3, 5, 6
            // 3 -> 2, 6
            // 3 <- 1, 4
            // 4 -> 3, 6
            // 4 <- 1, 7
            // 5 -> 2, 7, 8
            // 5 <- 2, 8
            // 6 -> 2
            // 6 <- 3, 4
            // 7 -> 4
            // 7 <- 5, 8
            // 8 -> 5, 7
            // 8 <- 5
            // 9 ->
            // 9 <-
            graph.AddEdge(1, 3);
            graph.AddEdge(1, 4);
            graph.AddEdge(2, 1);
            graph.AddEdge(2, 5);
            graph.AddEdge(3, 2);
            graph.AddEdge(3, 6);
            graph.AddEdge(4, 3);
            graph.AddEdge(4, 6);
            graph.AddEdge(5, 2);
            graph.AddEdge(5, 7);
            graph.AddEdge(5, 8);
            graph.AddEdge(6, 2);
            graph.AddEdge(7, 4);
            graph.AddEdge(8, 5);
            graph.AddEdge(8, 7);

            Assert.IsTrue(graph.EdgesCount == 15);

            Assert.IsTrue(graph.ContainsVertex(3));
            Assert.IsTrue(graph.ContainsEdge(3, 2));
            Assert.IsTrue(graph.ContainsEdge(3, 6));
            Assert.IsTrue(graph.ContainsEdge(1, 3));
            Assert.IsTrue(graph.ContainsEdge(4, 3));
            graph.RemoveVertex(3);
            Assert.IsFalse(graph.ContainsVertex(3));
            Assert.IsFalse(graph.ContainsEdge(3, 2));
            Assert.IsFalse(graph.ContainsEdge(3, 6));
            Assert.IsFalse(graph.ContainsEdge(1, 3));
            Assert.IsFalse(graph.ContainsEdge(4, 3));

            Assert.IsTrue(graph.EdgesCount == 11);

            Assert.IsTrue(graph.ContainsVertex(5));
            Assert.IsTrue(graph.ContainsEdge(5, 2));
            Assert.IsTrue(graph.ContainsEdge(5, 7));
            Assert.IsTrue(graph.ContainsEdge(5, 8));
            Assert.IsTrue(graph.ContainsEdge(2, 5));
            Assert.IsTrue(graph.ContainsEdge(8, 5));
            graph.RemoveVertex(5);
            Assert.IsFalse(graph.ContainsVertex(5));
            Assert.IsFalse(graph.ContainsEdge(5, 2));
            Assert.IsFalse(graph.ContainsEdge(5, 7));
            Assert.IsFalse(graph.ContainsEdge(5, 8));
            Assert.IsFalse(graph.ContainsEdge(2, 5));
            Assert.IsFalse(graph.ContainsEdge(8, 5));

            Assert.IsTrue(graph.EdgesCount == 6);
        }
Example #6
0
        public void CheckingIfVerticesAndEdgesAreAddedProperly()
        {
            var vertices = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };

            var graph = new DirectedALGraph <int>();

            graph.AddVertices(vertices);

            Assert.IsTrue(graph.VerticesCount == vertices.Length);

            foreach (var vertex in vertices)
            {
                Assert.IsTrue(graph.ContainsVertex(vertex));
            }

            // Graph is:
            // 1 -> 3, 4
            // 1 <- 2
            // 2 -> 1, 5
            // 2 <- 3, 5, 6
            // 3 -> 2, 6
            // 3 <- 1, 4
            // 4 -> 3, 6
            // 4 <- 1, 7
            // 5 -> 2, 7, 8
            // 5 <- 2, 8
            // 6 -> 2
            // 6 <- 3, 4
            // 7 -> 4
            // 7 <- 5, 8
            // 8 -> 5, 7
            // 8 <- 5
            // 9 ->
            // 9 <-
            graph.AddEdge(1, 3);
            graph.AddEdge(1, 4);
            graph.AddEdge(2, 1);
            graph.AddEdge(2, 5);
            graph.AddEdge(3, 2);
            graph.AddEdge(3, 6);
            graph.AddEdge(4, 3);
            graph.AddEdge(4, 6);
            graph.AddEdge(5, 2);
            graph.AddEdge(5, 7);
            graph.AddEdge(5, 8);
            graph.AddEdge(6, 2);
            graph.AddEdge(7, 4);
            graph.AddEdge(8, 5);
            graph.AddEdge(8, 7);

            Assert.IsTrue(graph.EdgesCount == 15);

            Assert.IsTrue(graph.ContainsEdge(1, 3));
            Assert.IsTrue(graph.ContainsEdge(1, 4));
            Assert.IsTrue(graph.ContainsEdge(2, 1));
            Assert.IsTrue(graph.ContainsEdge(2, 5));
            Assert.IsTrue(graph.ContainsEdge(3, 2));
            Assert.IsTrue(graph.ContainsEdge(3, 6));
            Assert.IsTrue(graph.ContainsEdge(4, 3));
            Assert.IsTrue(graph.ContainsEdge(4, 6));
            Assert.IsTrue(graph.ContainsEdge(5, 2));
            Assert.IsTrue(graph.ContainsEdge(5, 7));
            Assert.IsTrue(graph.ContainsEdge(5, 8));
            Assert.IsTrue(graph.ContainsEdge(6, 2));
            Assert.IsTrue(graph.ContainsEdge(7, 4));
            Assert.IsTrue(graph.ContainsEdge(8, 5));
            Assert.IsTrue(graph.ContainsEdge(8, 7));

            Assert.IsFalse(graph.ContainsEdge(1, 2));
            Assert.IsFalse(graph.ContainsEdge(1, 5));
            Assert.IsFalse(graph.ContainsEdge(1, 6));
            Assert.IsFalse(graph.ContainsEdge(1, 7));
            Assert.IsFalse(graph.ContainsEdge(1, 8));
            Assert.IsFalse(graph.ContainsEdge(2, 3));
            Assert.IsFalse(graph.ContainsEdge(2, 4));
            Assert.IsFalse(graph.ContainsEdge(2, 6));
            Assert.IsFalse(graph.ContainsEdge(2, 7));
            Assert.IsFalse(graph.ContainsEdge(2, 8));
            Assert.IsFalse(graph.ContainsEdge(3, 1));
            Assert.IsFalse(graph.ContainsEdge(3, 4));
            Assert.IsFalse(graph.ContainsEdge(3, 5));
            Assert.IsFalse(graph.ContainsEdge(3, 7));
            Assert.IsFalse(graph.ContainsEdge(3, 8));
            Assert.IsFalse(graph.ContainsEdge(4, 1));
            Assert.IsFalse(graph.ContainsEdge(4, 2));
            Assert.IsFalse(graph.ContainsEdge(4, 5));
            Assert.IsFalse(graph.ContainsEdge(4, 7));
            Assert.IsFalse(graph.ContainsEdge(4, 8));
            Assert.IsFalse(graph.ContainsEdge(5, 1));
            Assert.IsFalse(graph.ContainsEdge(5, 3));
            Assert.IsFalse(graph.ContainsEdge(5, 4));
            Assert.IsFalse(graph.ContainsEdge(5, 6));
            Assert.IsFalse(graph.ContainsEdge(6, 1));
            Assert.IsFalse(graph.ContainsEdge(6, 3));
            Assert.IsFalse(graph.ContainsEdge(6, 4));
            Assert.IsFalse(graph.ContainsEdge(6, 5));
            Assert.IsFalse(graph.ContainsEdge(6, 7));
            Assert.IsFalse(graph.ContainsEdge(6, 8));
            Assert.IsFalse(graph.ContainsEdge(7, 1));
            Assert.IsFalse(graph.ContainsEdge(7, 2));
            Assert.IsFalse(graph.ContainsEdge(7, 3));
            Assert.IsFalse(graph.ContainsEdge(7, 5));
            Assert.IsFalse(graph.ContainsEdge(7, 6));
            Assert.IsFalse(graph.ContainsEdge(7, 8));
            Assert.IsFalse(graph.ContainsEdge(8, 1));
            Assert.IsFalse(graph.ContainsEdge(8, 2));
            Assert.IsFalse(graph.ContainsEdge(8, 3));
            Assert.IsFalse(graph.ContainsEdge(8, 4));
            Assert.IsFalse(graph.ContainsEdge(8, 6));
        }
Example #7
0
        public void BipartiteColoringOnDirectedGraphCheck()
        {
            var vertices = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };

            var graph = new DirectedALGraph <int>();

            graph.AddVertices(vertices);

            // Graph is:
            // 1 -> 3, 4
            // 1 <- 2
            // 2 -> 1, 5
            // 2 <- 5, 6
            // 3 -> 6
            // 3 <- 1
            // 4 -> 6
            // 4 <- 1, 5
            // 5 -> 2, 4, 8
            // 5 <- 2, 8
            // 6 -> 2
            // 6 <- 3, 4
            // 7 -> 4
            // 7 <- 5, 8
            // 8 -> 5, 7
            // 8 <- 5
            // 9 ->
            // 9 <-
            graph.AddEdge(1, 3);
            graph.AddEdge(1, 4);
            graph.AddEdge(2, 1);
            graph.AddEdge(2, 5);
            graph.AddEdge(3, 6);
            graph.AddEdge(4, 6);
            graph.AddEdge(5, 2);
            graph.AddEdge(5, 4);
            graph.AddEdge(5, 8);
            graph.AddEdge(6, 2);
            graph.AddEdge(7, 4);
            graph.AddEdge(8, 5);
            graph.AddEdge(8, 7);

            Dictionary <int, BipartiteColor> verticesColors;

            Assert.IsTrue(graph.TryGetBipartiteColoring(out verticesColors));

            foreach (var edge in graph.Edges)
            {
                Assert.IsTrue(verticesColors[edge.Source] != verticesColors[edge.Destination]);
            }

            // Check with not bipartite graph

            graph = new DirectedALGraph <int>();

            graph.AddVertices(vertices);

            // Graph is:
            // 1 -> 3, 4
            // 1 <- 2
            // 2 -> 1, 5
            // 2 <- 3, 5, 6
            // 3 -> 2, 6
            // 3 <- 1, 4
            // 4 -> 3, 6
            // 4 <- 1, 7
            // 5 -> 2, 7, 8
            // 5 <- 2, 8
            // 6 -> 2
            // 6 <- 3, 4
            // 7 -> 4
            // 7 <- 5, 8
            // 8 -> 5, 7
            // 8 <- 5
            // 9 ->
            // 9 <-
            graph.AddEdge(1, 3);
            graph.AddEdge(1, 4);
            graph.AddEdge(2, 1);
            graph.AddEdge(2, 5);
            graph.AddEdge(3, 2);
            graph.AddEdge(3, 6);
            graph.AddEdge(4, 3);
            graph.AddEdge(4, 6);
            graph.AddEdge(5, 2);
            graph.AddEdge(5, 7);
            graph.AddEdge(5, 8);
            graph.AddEdge(6, 2);
            graph.AddEdge(7, 4);
            graph.AddEdge(8, 5);
            graph.AddEdge(8, 7);

            Assert.IsFalse(graph.TryGetBipartiteColoring(out verticesColors));
        }