public void FourComponents()
{
DirectedGraph<char> graph = new DirectedGraph<char>
{
{ 'a', new char[] { 'b' } },
{ 'b', new char[] { 'e', 'f' } },
{ 'e', new char[] { 'a', 'f' } },
{ 'c', new char[] { 'd', 'g' } },
{ 'd', new char[] { 'c', 'h' } },
{ 'f', new char[] { 'g' } },
{ 'g', new char[] { 'f', 'h' } },
{ 'h', new char[] { 'h' } },
};
IEnumerable<char> vertexes = new char[]{ 'b', 'e', 'a', 'c', 'd', 'g', 'f', 'h' };
StronglyConenctedComponentsAlgorithm<char> alg = new StronglyConenctedComponentsAlgorithm<char>(graph, vertexes);
alg.Run();
var scc = alg.StronglyConnectedComponents;
Assert.AreEqual(graph.Keys.Count, scc.Keys.Count);
// scc 1
Assert.AreEqual(1, scc['b'].Count);
Assert.AreEqual('e', scc['b'][0]);
Assert.AreEqual(1, scc['e'].Count);
Assert.AreEqual('a', scc['e'][0]);
Assert.AreEqual(0, scc['a'].Count);
// scc 2
Assert.AreEqual(1, scc['g'].Count);
Assert.AreEqual('f', scc['g'][0]);
Assert.AreEqual(0, scc['f'].Count);
// scc 3
Assert.AreEqual(1, scc['c'].Count);
Assert.AreEqual('d', scc['c'][0]);
Assert.AreEqual(0, scc['d'].Count);
// scc 3
Assert.AreEqual(0, scc['h'].Count);
}
public void SingleScc()
{
DirectedGraph<char> graph = new DirectedGraph<char>
{
{ 'a', new char[] { 'b', 'c' } },
{ 'b', new char[0] },
{ 'c', new char[0] }
};
StronglyConenctedComponentsAlgorithm<char> alg = new StronglyConenctedComponentsAlgorithm<char>(graph);
alg.Run();
DirectedGraph<char> scc = alg.StronglyConnectedComponents;
Assert.AreEqual(graph.Keys.Count, scc.Keys.Count);
Assert.AreEqual(2, graph['a'].Count);
Assert.AreEqual(0, graph['b'].Count);
Assert.AreEqual(0, graph['c'].Count);
Assert.AreEqual(true, graph['a'].Contains('b'));
Assert.AreEqual(true, graph['a'].Contains('c'));
}
public void ThreeNodeCycle()
{
DirectedGraph<char> graph = new DirectedGraph<char>
{
{ 'a', new char[] { 'b' } },
{ 'b', new char[] { 'c' } },
{ 'c', new char[] { 'a' } }
};
IEnumerable<char> vertexes = new char[]{ 'b', 'c', 'a' };
StronglyConenctedComponentsAlgorithm<char> alg = new StronglyConenctedComponentsAlgorithm<char>(graph, vertexes);
alg.Run();
DirectedGraph<char> scc = alg.StronglyConnectedComponents;
Assert.AreEqual(graph.Count, scc.Count);
Assert.AreEqual(1, scc['b'].Count);
Assert.AreEqual('c', scc['b'].First());
Assert.AreEqual(1, scc['c'].Count);
Assert.AreEqual('a', scc['c'].First());
Assert.AreEqual(0, scc['a'].Count);
}