public List<Edge<int>> mfas(BidirectionalGraph<int, Edge<int>> G)
{
List<Edge<int>> F = new List<Edge<int>>();
IDictionary<int, int> P = new Dictionary<int, int>();
int sccCount = G.StronglyConnectedComponents(out P);
if (sccCount == 0)
{
return F;
}
if (sccCount == 1)
{
Tuple<List<int>, List<int>> T = bisect(G);
F = mfas(subGraph(T.Item1, G));
F.AddRange(mfas(subGraph(T.Item2, G)));
F.AddRange(fromV2toV1(T, G));
}
else
{
var scc = new HashSet<int>(P.Values);
foreach (int k in scc)
{
List<int> S = P.Select(x => x).Where(x => x.Value == k).Select(x => x.Key).ToList<int>();
F.AddRange(mfas(subGraph(S, G)));
}
}
return F;
}
public static StronglyConntectedComponents <T> Sccs <T>(this BidirectionalGraph <T, Edge <T> > graph)
{
IDictionary <T, int> sccNumbering;
graph.StronglyConnectedComponents(out sccNumbering);
return(new StronglyConntectedComponents <T>(sccNumbering, sccNumbering.TurnAround()));
}
/// <summary>
/// Adds a new coercion rule. Trys to avoid cyclic implicit casts chains.
/// </summary>
/// <typeparam name="TOriginalType"></typeparam>
/// <typeparam name="TCastingType"></typeparam>
/// <param name="kind"></param>
/// <param name="cast"></param>
public void AddCoercionRule <TOriginalType, TCastingType>(CoercionKind kind, Func <TOriginalType, TCastingType> cast)
{
var original = typeof(TOriginalType);
var casting = typeof(TCastingType);
if (GetTypeByNative(original) == null)
{
throw new UnknownTypeException(original);
}
if (GetTypeByNative(casting) == null)
{
throw new UnknownTypeException(casting);
}
var rule = new CoercionRule(kind, original, casting, a => cast((TOriginalType)a));
if (allCoercionRules.TryGetEdge(original, casting, out TaggedEdge <Type, CoercionRule> existingEdge))
{
throw new InvalidOperationException("Such a rule does already exist!");
}
var edge = new TaggedEdge <System.Type, CoercionRule>(original, casting, rule);
if (kind == CoercionKind.Implicit)
{
implicitCoercionRules.AddVertex(original);
implicitCoercionRules.AddVertex(casting);
implicitCoercionRules.AddEdge(edge);
if (implicitCoercionRules.StronglyConnectedComponents(out IDictionary <Type, int> components) != implicitCoercionRules.Vertices.Count())
{
implicitCoercionRules.RemoveEdge(edge);
throw new InvalidOperationException("This action would create an implicit conversion cycle!");
}
}
allCoercionRules.AddVertex(original);
allCoercionRules.AddVertex(casting);
allCoercionRules.AddEdge(edge);
Debug.WriteLine($"- added coercion rule from '{original.Name}' to '{casting.Name}'");
}
