public void DFSGraphEdgeRecursiveTest()
{
var undirectedGraphWithCycles = new GraphAdjacentLists <int>(GraphAdjacentLists <int> .DirectedGraphEnum.Undirected);
undirectedGraphWithCycles.AddVertex(1);
undirectedGraphWithCycles.AddVertex(2);
undirectedGraphWithCycles.AddVertex(3);
undirectedGraphWithCycles.AddVertex(4);
undirectedGraphWithCycles.AddVertex(5);
undirectedGraphWithCycles.AddVertex(6);
undirectedGraphWithCycles.AddEdge(1, 6);
undirectedGraphWithCycles.AddEdge(1, 2);
undirectedGraphWithCycles.AddEdge(2, 3);
undirectedGraphWithCycles.AddEdge(3, 4);
undirectedGraphWithCycles.AddEdge(4, 5);
undirectedGraphWithCycles.AddEdge(5, 2);
undirectedGraphWithCycles.AddEdge(5, 1);
var directedGraphWithCycles = new GraphAdjacentLists <int>(GraphAdjacentLists <int> .DirectedGraphEnum.Directed);
directedGraphWithCycles.AddVertex(1);
directedGraphWithCycles.AddVertex(2);
directedGraphWithCycles.AddVertex(3);
directedGraphWithCycles.AddVertex(4);
directedGraphWithCycles.AddVertex(5);
directedGraphWithCycles.AddVertex(6);
directedGraphWithCycles.AddEdge(1, 6);
directedGraphWithCycles.AddEdge(1, 2);
directedGraphWithCycles.AddEdge(2, 3);
directedGraphWithCycles.AddEdge(3, 4);
directedGraphWithCycles.AddEdge(4, 5);
directedGraphWithCycles.AddEdge(5, 2);
directedGraphWithCycles.AddEdge(5, 1);
var undirectedGraphWithoutCycles = new GraphAdjacentLists <int>(GraphAdjacentLists <int> .DirectedGraphEnum.Undirected);
undirectedGraphWithoutCycles.AddVertex(1);
undirectedGraphWithoutCycles.AddVertex(2);
undirectedGraphWithoutCycles.AddVertex(3);
undirectedGraphWithoutCycles.AddVertex(4);
undirectedGraphWithoutCycles.AddVertex(5);
undirectedGraphWithoutCycles.AddVertex(6);
undirectedGraphWithoutCycles.AddEdge(1, 6);
undirectedGraphWithoutCycles.AddEdge(1, 2);
undirectedGraphWithoutCycles.AddEdge(2, 3);
undirectedGraphWithoutCycles.AddEdge(3, 4);
undirectedGraphWithoutCycles.AddEdge(4, 5);
Assert.Equal(new []
{
"tree edge: 1-6",
"tree edge: 1-2",
"tree edge: 2-3",
"tree edge: 3-4",
"tree edge: 4-5",
"back edge: 5-2",
"back edge: 5-1"
}, DFS.DFSGraphEdgesRecursive(undirectedGraphWithCycles, 1));
Assert.True(DFS.DFSGraphHasCycles(undirectedGraphWithCycles));
Assert.Equal(new []
{
"tree edge: 1-6",
"tree edge: 1-2",
"tree edge: 2-3",
"tree edge: 3-4",
"tree edge: 4-5",
"back edge: 5-2",
"back edge: 5-1"
}, DFS.DFSGraphEdgesRecursive(directedGraphWithCycles, 1));
Assert.True(DFS.DFSGraphHasCycles(directedGraphWithCycles));
Assert.Equal(new []
{
"tree edge: 1-6",
"tree edge: 1-2",
"tree edge: 2-3",
"tree edge: 3-4",
"tree edge: 4-5"
}, DFS.DFSGraphEdgesRecursive(undirectedGraphWithoutCycles, 1));
Assert.False(DFS.DFSGraphHasCycles(undirectedGraphWithoutCycles));
}