public void FindStrongConnectedComponentsFindsExpectedComponents()
{
// See https://upload.wikimedia.org/wikipedia/commons/6/60/Tarjan%27s_Algorithm_Animation.gif
var graph = new Graph <object, object>(
Enumerable.Range(1, 8).Select(vertexId => new Vertex <object>((uint)vertexId)),
new []
{
new Edge <object>(0, 1, 2, isDirected: true),
new Edge <object>(1, 2, 3, isDirected: true),
new Edge <object>(2, 3, 1, isDirected: true),
new Edge <object>(3, 4, 2, isDirected: true),
new Edge <object>(4, 4, 3, isDirected: true),
new Edge <object>(5, 4, 5, isDirected: true),
new Edge <object>(6, 5, 4, isDirected: true),
new Edge <object>(7, 5, 6, isDirected: true),
new Edge <object>(8, 6, 3, isDirected: true),
new Edge <object>(9, 6, 7, isDirected: true),
new Edge <object>(10, 7, 6, isDirected: true),
new Edge <object>(11, 8, 6, isDirected: true),
new Edge <object>(12, 8, 7, isDirected: true),
new Edge <object>(13, 8, 8, isDirected: true)
});
var expected = new List <IList <uint> >
{
new uint[] { 1, 2, 3 },
new uint[] { 4, 5 },
new uint[] { 6, 7 },
new uint[] { 8 }
};
var actual = GraphAlgorithms.FindStronglyConnectedComponents(graph);
Assert.That(actual.Count, Is.EqualTo(expected.Count));
foreach (var vertexIds in expected)
{
var referenceVertex = graph.GetVertexFromId(vertexIds[0]);
var matchingActual = actual.Single(c => c.Contains(referenceVertex));
CollectionAssert.AreEquivalent(vertexIds, matchingActual.Select(c => c.Id));
}
}
