/// <inheritdoc />
protected override void InternalCompute()
{
ICancelManager cancelManager = Services.CancelManager;
while (_heap.Count != 0)
{
if (cancelManager.IsCancelling)
{
return;
}
TVertex vertex = _heap.Dequeue();
int degree = Degrees[vertex];
// 0 => isolated vertex
// 1 => single adjacent edge
if (degree != 0 && degree != 1 && !AllowCyclicGraph)
{
throw new NonAcyclicGraphException();
}
_sortedVertices.Add(vertex);
OnVertexAdded(vertex);
// Update the count of its adjacent vertices
UpdateAdjacentDegree(vertex);
}
SortedVertices = _sortedVertices.ToArray();
#region Local function
void UpdateAdjacentDegree(TVertex vertex)
{
foreach (TEdge edge in VisitedGraph.AdjacentEdges(vertex).Where(e => !e.IsSelfEdge()))
{
TVertex other = edge.GetOtherVertex(vertex);
--Degrees[other];
if (Degrees[other] < 0 && !AllowCyclicGraph)
{
throw new InvalidOperationException("Degree is negative, and cannot be.");
}
if (_heap.Contains(other))
{
_heap.Update(other);
}
}
}
#endregion
}
/// <inheritdoc />
protected override void InternalCompute()
{
ICancelManager cancelManager = Services.CancelManager;
InitializeInDegrees();
while (_heap.Count != 0)
{
if (cancelManager.IsCancelling)
{
return;
}
TVertex vertex = _heap.Dequeue();
if (Degrees[vertex] != 0 && !AllowCyclicGraph)
{
throw new NonAcyclicGraphException();
}
SortedVertices.Add(vertex);
OnVertexAdded(vertex);
// Update the count of its adjacent vertices
UpdateAdjacentDegree(vertex);
}
#region Local function
void UpdateAdjacentDegree(TVertex vertex)
{
foreach (TEdge edge in VisitedGraph.AdjacentEdges(vertex).Where(e => !e.IsSelfEdge()))
{
--Degrees[edge.Target];
if (Degrees[edge.Target] < 0 && !AllowCyclicGraph)
{
throw new InvalidOperationException("Degree is negative, and cannot be.");
}
if (_heap.Contains(edge.Target))
{
_heap.Update(edge.Target);
}
}
}
#endregion
}
