public void GraphWithSelfEdge()
{
var graph = new UndirectedGraph <int, Edge <int> >();
graph.AddVerticesAndEdgeRange(new[]
{
new Edge <int>(0, 1),
new Edge <int>(1, 2),
new Edge <int>(1, 3),
new Edge <int>(2, 3),
new Edge <int>(2, 2),
new Edge <int>(3, 4)
});
var algorithm = new UndirectedTopologicalSortAlgorithm <int, Edge <int> >(graph);
Assert.Throws <NonAcyclicGraphException>(() => algorithm.Compute());
algorithm = new UndirectedTopologicalSortAlgorithm <int, Edge <int> >(graph)
{
AllowCyclicGraph = true
};
algorithm.Compute();
// Order in undirected graph is some strange thing,
// here the order is more vertices ordered by depth
CollectionAssert.AreEqual(
new[] { 0, 1, 2, 3, 4 },
algorithm.SortedVertices);
}
public void SimpleGraph()
{
var graph = new UndirectedGraph <int, Edge <int> >();
graph.AddVerticesAndEdgeRange(new[]
{
new Edge <int>(1, 2),
new Edge <int>(2, 3),
new Edge <int>(4, 2),
new Edge <int>(4, 5),
new Edge <int>(5, 6),
new Edge <int>(7, 5),
new Edge <int>(7, 8)
});
var algorithm = new UndirectedTopologicalSortAlgorithm <int, Edge <int> >(graph);
algorithm.Compute();
// Order in undirected graph is some strange thing,
// here the order is more vertices ordered by depth
CollectionAssert.AreEqual(
new[] { 1, 2, 4, 5, 7, 8, 6, 3 },
algorithm.SortedVertices);
}
public void Compute([PexAssumeNotNull]IUndirectedGraph<string, Edge<string>> g)
{
UndirectedTopologicalSortAlgorithm<string, Edge<string>> topo =
new UndirectedTopologicalSortAlgorithm<string, Edge<string>>(g);
topo.AllowCyclicGraph = true;
topo.Compute();
Display(topo);
}
public static (string[], string) Get(UndirectedGraph <string, TaggedEdge <string, string> > graph)
{
var algorithm = new UndirectedTopologicalSortAlgorithm <string, TaggedEdge <string, string> >(graph);
try
{
algorithm.Compute();
return(algorithm.SortedVertices, null);
}
catch (System.Exception ex)
{
return(null, ex.Message);
}
}
private static void RunUndirectedTopologicalSortAndCheck <TVertex, TEdge>(
[NotNull] IUndirectedGraph <TVertex, TEdge> graph,
bool allowCycles)
where TEdge : IEdge <TVertex>
{
var algorithm = new UndirectedTopologicalSortAlgorithm <TVertex, TEdge>(graph)
{
AllowCyclicGraph = allowCycles
};
algorithm.Compute();
Assert.IsNotNull(algorithm.SortedVertices);
Assert.AreEqual(graph.VertexCount, algorithm.SortedVertices.Length);
}
public void UndirectedTopologicalSort_Throws()
{
var cyclicGraph = new UndirectedGraph <int, Edge <int> >();
cyclicGraph.AddVerticesAndEdgeRange(new[]
{
new Edge <int>(1, 2),
new Edge <int>(2, 3),
new Edge <int>(1, 4),
new Edge <int>(3, 1)
});
var algorithm = new UndirectedTopologicalSortAlgorithm <int, Edge <int> >(cyclicGraph);
Assert.Throws <NonAcyclicGraphException>(() => algorithm.Compute());
algorithm = new UndirectedTopologicalSortAlgorithm <int, Edge <int> >(cyclicGraph)
{
AllowCyclicGraph = true
};
Assert.DoesNotThrow(() => algorithm.Compute());
}
public void SimpleGraphOneToAnother()
{
var graph = new UndirectedGraph <int, Edge <int> >();
graph.AddVerticesAndEdgeRange(new[]
{
new Edge <int>(0, 1),
new Edge <int>(1, 2),
new Edge <int>(1, 3),
new Edge <int>(3, 4)
});
var algorithm = new UndirectedTopologicalSortAlgorithm <int, Edge <int> >(graph);
algorithm.Compute();
// Order in undirected graph is some strange thing,
// here the order is more vertices ordered by depth
CollectionAssert.AreEqual(
new[] { 0, 1, 3, 4, 2 },
algorithm.SortedVertices);
}