public void FindScc_WhenSingleComponent_ThenAllVertices()
{
// given
var graph = new DirectedSimpleGraph <int, object, object>(Enumerable.Range(0, 7));
graph.AddEdgeBetween(graph[0], graph[1]);
graph.AddEdgeBetween(graph[1], graph[2]);
graph.AddEdgeBetween(graph[2], graph[3]);
graph.AddEdgeBetween(graph[3], graph[4]);
graph.AddEdgeBetween(graph[4], graph[5]);
graph.AddEdgeBetween(graph[5], graph[6]);
graph.AddEdgeBetween(graph[6], graph[0]);
// when
List <HashSet <Vertex <int> > > result = graph.FindScc();
// then
result.Should().BeEquivalentTo(new[] { new HashSet <Vertex <int> >(graph.Vertices) });
}
public void FindScc_WhenManyComponents_ThenAllListed()
{
// given
var graph = new DirectedSimpleGraph <int, object, object>(Enumerable.Range(0, 10));
graph.AddEdgeBetween(graph[0], graph[4]);
graph.AddEdgeBetween(graph[0], graph[5]);
graph.AddEdgeBetween(graph[1], graph[0]);
graph.AddEdgeBetween(graph[2], graph[3]);
graph.AddEdgeBetween(graph[3], graph[1]);
graph.AddEdgeBetween(graph[4], graph[1]);
graph.AddEdgeBetween(graph[4], graph[3]);
graph.AddEdgeBetween(graph[6], graph[5]);
graph.AddEdgeBetween(graph[6], graph[9]);
graph.AddEdgeBetween(graph[7], graph[4]);
graph.AddEdgeBetween(graph[7], graph[6]);
graph.AddEdgeBetween(graph[8], graph[3]);
graph.AddEdgeBetween(graph[8], graph[7]);
graph.AddEdgeBetween(graph[9], graph[8]);
// when
List <HashSet <Vertex <int> > > result = graph.FindScc();
// then
result.Should().BeEquivalentTo(
new[] {
new HashSet <Vertex <int> > {
graph[0], graph[1], graph[3], graph[4]
},
new HashSet <Vertex <int> > {
graph[2]
},
new HashSet <Vertex <int> > {
graph[5]
},
new HashSet <Vertex <int> > {
graph[6], graph[7], graph[8], graph[9]
}
});
}
public void FindScc_WhenEmptyGraph_ThenEachVertexIsComponent()
{
// given
var graph = new DirectedSimpleGraph <int, object, object>(Enumerable.Range(0, 4));
// when
List <HashSet <Vertex <int> > > result = graph.FindScc();
// then
result.Should().BeEquivalentTo(
new[] {
new HashSet <Vertex <int> > {
graph[0]
},
new HashSet <Vertex <int> > {
graph[1]
},
new HashSet <Vertex <int> > {
graph[2]
},
new HashSet <Vertex <int> > {
graph[3]
}
});
}