bool IBidirectionalIncidenceGraph <TVertex, TEdge> .TryGetInEdges(TVertex v, out IEnumerable <TEdge> edges)
{
IBidirectionalIncidenceGraph <TVertex, TEdge> ithis = this;
Contract.Requires(v != null);
Contract.Requires(ithis.ContainsVertex(v));
Contract.Ensures(Contract.Result <bool>() == ithis.ContainsVertex(v));
Contract.Ensures(!Contract.Result <bool>() || Contract.ValueAtReturn(out edges) != null);
Contract.Ensures(!Contract.Result <bool>() ||
Contract.ValueAtReturn(out edges).All(edge => edge != null && edge.Target.Equals(v)
)
);
edges = null;
return(default(bool));
}
int IBidirectionalIncidenceGraph <TVertex, TEdge> .Degree(TVertex v)
{
IBidirectionalIncidenceGraph <TVertex, TEdge> ithis = this;
Contract.Requires(v != null);
Contract.Requires(ithis.ContainsVertex(v));
Contract.Ensures(Contract.Result <int>() == ithis.InDegree(v) + ithis.OutDegree(v));
return(default(int));
}
TEdge IBidirectionalIncidenceGraph <TVertex, TEdge> .InEdge(TVertex v, int index)
{
IBidirectionalIncidenceGraph <TVertex, TEdge> ithis = this;
Contract.Requires(v != null);
Contract.Requires(ithis.ContainsVertex(v));
Contract.Ensures(Contract.Result <TEdge>().Equals(Enumerable.ElementAt(ithis.InEdges(v), index)));
return(default(TEdge));
}
bool IBidirectionalIncidenceGraph <TVertex, TEdge> .IsInEdgesEmpty(TVertex v)
{
IBidirectionalIncidenceGraph <TVertex, TEdge> ithis = this;
Contract.Requires(v != null);
Contract.Requires(ithis.ContainsVertex(v));
Contract.Ensures(Contract.Result <bool>() == (ithis.InDegree(v) == 0));
return(default(bool));
}
IEnumerable <TEdge> IBidirectionalIncidenceGraph <TVertex, TEdge> .InEdges(TVertex v)
{
IBidirectionalIncidenceGraph <TVertex, TEdge> ithis = this;
Contract.Requires(v != null);
Contract.Requires(ithis.ContainsVertex(v));
Contract.Ensures(Contract.Result <IEnumerable <TEdge> >() != null);
Contract.Ensures(Contract.Result <IEnumerable <TEdge> >().All(edge => edge != null && edge.Target.Equals(v)
)
);
return(default(IEnumerable <TEdge>));
}