public IVertex ParentVertex(IVertex v)
{
if (v == null)
{
throw new ArgumentNullException("v");
}
if (this.Wrapped.InDegree(v) > 1)
{
throw new MultipleInEdgeException(v.get_ID().ToString());
}
return Traversal.FirstSourceVertex(this.Wrapped.InEdges(v));
}
private int FetchIndex(IVertex v)
{
for (int i = 0; i < base.List.Count; i++)
{
IList list = (IList) base.List[i];
if ((list.Count > 0) && (((IVertex) list[0]).get_ID() == v.get_ID()))
{
return i;
}
}
return -1;
}