Esempio n. 1
0
        private void Walkup(Vertex <T> vertex, IEdge <Vertex <T> > edge)
        {
            var source = edge.Source;
            var target = edge.Target;

            if (source.Equals(target))
            {
                selfLoopsNew.Add(edge);
                return;
            }

            var w = vertex.Equals(source) ? target : vertex;

            if (w.DFSNumber < vertex.DFSNumber || edge.Equals(w.DFSEdge))
            {
                return;
            }

            w.BackEdges.Add(edge);
            var timestamp = vertex.DFSNumber;

            w.BackedgeFlag = timestamp;

            var leadVertex = w;

            while (true)
            {
                var foundRoot = true;

                // Move to the root of the current bicomp or the first visited
                // vertex on the bicomp by going up each side in parallel
                foreach (var faceVertex in IterateBothSides(leadVertex))
                {
                    if (faceVertex.Visited == timestamp)
                    {
                        foundRoot = false;
                        break;
                    }

                    leadVertex         = faceVertex;
                    leadVertex.Visited = timestamp;
                }

                // If we've found the root of a bicomp through a path we haven't
                // seen before, update pertinent_roots with a handle to the
                // current bicomp. Otherwise, we've just seen a path we've been
                // up before, so break out of the main while loop.
                if (foundRoot)
                {
                    var dfsChild = leadVertex.CanonicalDFSChild;
                    var parent   = dfsChild.Parent;

                    dfsChild.DFSChildHandle.FirstVertex.Visited  = timestamp;
                    dfsChild.DFSChildHandle.SecondVertex.Visited = timestamp;

                    if (dfsChild.LowPoint < vertex.DFSNumber ||
                        dfsChild.LeastAncestor < vertex.DFSNumber
                        )
                    {
                        parent.PertinentRoots.AddLast(dfsChild.DFSChildHandle);
                    }
                    else
                    {
                        parent.PertinentRoots.AddFirst(dfsChild.DFSChildHandle);
                    }

                    if (parent != vertex && parent.Visited != timestamp)
                    {
                        leadVertex = parent;
                    }
                    else
                    {
                        break;
                    }
                }
                else
                {
                    break;
                }
            }
        }
Esempio n. 2
0
        /// <summary>
        /// すでに辺が作成されているか調べます。
        /// </summary>
        /// <param name="ed">調べたい辺</param>
        protected bool CheckEdgeExist(IEdge ed)
        {
            foreach (IEdge item in edge)
                if (ed.Equals(item))
                    return true;

            return false;
        }