//compute Dijkstra for each of the boundary nodes
public void PrecomputeArcFlags()
{
for (int i = 0; i < BoundNodes.Count; i++)
{
Node boundNode = BoundNodes[i];
DijkstraAlgorithm dij = new DijkstraAlgorithm(Grapph);
dij.GetShortPath(boundNode.Id, "-1");
//set flag and save the parents into a list
Dictionary <string, string> parents = dij.Parents;
IEnumerator <string> str = parents.Keys.GetEnumerator();
while (str.MoveNext())
{
string currentNodeId = str.Current;
string parentNodeId = parents[currentNodeId];
if (parentNodeId != "-1")
{
Collection <Arc> allarcs = Grapph.AdjacentArcs[currentNodeId];
for (int k = 0; k < allarcs.Count; k++)
{
Arc arc = allarcs[k];
if (arc.HeadNode.Id == parentNodeId)
{
arc.ArcFlag = true;
}
}
}
}
}
}
public double ComputeShprtPath(string sourceId, string targetId)
{
CompBoundNodes();
PrecomputeArcFlags();
DijkstraAlgorithm dij = new DijkstraAlgorithm(Grapph);
return(dij.GetShortPath(sourceId, targetId));
}
//dijkstra from a set of nodes
//怎样把已经访问过的节点在
public Dictionary <string, double> PreComputLandmarksDistances(string currentLandmarkId)
{
Dictionary <string, double> costDictionary = new Dictionary <string, double>();
DijkstraAlgorithm dijkstra = new DijkstraAlgorithm(Graph);
dijkstra.GetShortPath(currentLandmarkId, "-1");
costDictionary = dijkstra.VisitedNodeMarks;
return(costDictionary);
}
public double ComputeShortPath(string sourceNodeId, string targetNodeId)
{
Console.WriteLine(DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss:fff"));
DijkstraAlgorithm dij = new DijkstraAlgorithm(Graph);
dij.Heuristics = GetHeuristicDictionary(targetNodeId);
double cost = dij.GetShortPath(sourceNodeId, targetNodeId);
dij.ShortPathToString(sourceNodeId, targetNodeId);
Console.WriteLine(DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss:fff"));
return(cost);
}
static void Main(string[] args)
{
RoadNetwork rn = new RoadNetwork();
Node n1 = new Node("1", 0, 0);
Node n2 = new Node("2", 0, 0);
Node n3 = new Node("3", 0, 0);
Node n4 = new Node("4", 0, 0);
Node n5 = new Node("5", 0, 0);
Node n6 = new Node("6", 0, 0);
Arc arc12 = new Arc(n1, n2, 7);
Arc arc13 = new Arc(n1, n3, 9);
Arc arc16 = new Arc(n1, n6, 14);
Arc arc23 = new Arc(n2, n3, 10);
Arc arc24 = new Arc(n2, n4, 15);
Arc arc34 = new Arc(n3, n4, 11);
Arc arc36 = new Arc(n3, n6, 2);
Arc arc45 = new Arc(n4, n5, 6);
Arc arc65 = new Arc(n6, n5, 9);
Arc arc21 = new Arc(n2, n1, 7);
Arc arc31 = new Arc(n3, n1, 9);
Arc arc61 = new Arc(n6, n1, 14);
Arc arc32 = new Arc(n3, n2, 10);
Arc arc42 = new Arc(n4, n2, 15);
Arc arc43 = new Arc(n4, n3, 11);
Arc arc63 = new Arc(n6, n3, 2);
Arc arc54 = new Arc(n5, n4, 6);
Arc arc56 = new Arc(n6, n5, 9);
rn.Nodes.Add(n1);
rn.Nodes.Add(n2);
rn.Nodes.Add(n3);
rn.Nodes.Add(n4);
rn.Nodes.Add(n5);
rn.Nodes.Add(n6);
rn.Arcs.Add(arc12);
rn.Arcs.Add(arc13);
rn.Arcs.Add(arc16);
rn.AdjacentArcs.Add(n1.Id, rn.Arcs);
Collection <Arc> aa = new Collection <Arc>();
aa.Add(arc21);
aa.Add(arc23);
aa.Add(arc24);
rn.AdjacentArcs.Add(n2.Id, aa);
Collection <Arc> bb = new Collection <Arc>();
bb.Add(arc31);
bb.Add(arc32);
bb.Add(arc34);
bb.Add(arc36);
rn.AdjacentArcs.Add(n3.Id, bb);
Collection <Arc> cc = new Collection <Arc>();
cc.Add(arc42);
cc.Add(arc43);
cc.Add(arc45);
rn.AdjacentArcs.Add(n4.Id, cc);
Collection <Arc> dd = new Collection <Arc>();
dd.Add(arc63);
dd.Add(arc65);
dd.Add(arc61);
rn.AdjacentArcs.Add(n6.Id, dd);
Collection <Arc> ee = new Collection <Arc>();
ee.Add(arc56);
ee.Add(arc54);
rn.AdjacentArcs.Add(n5.Id, ee);
rn.MapNodes.Add("1", n1);
rn.MapNodes.Add("2", n2);
rn.MapNodes.Add("3", n3);
rn.MapNodes.Add("4", n4);
rn.MapNodes.Add("5", n5);
rn.MapNodes.Add("6", n6);
DijkstraAlgorithm dij = new DijkstraAlgorithm(rn);
double cost = dij.GetShortPath("1", "5");
dij.ShortPathToString("1", "5");
Console.WriteLine("******************************");
LandmarkAlgorithm landmark = new LandmarkAlgorithm(rn);
landmark.SelectLandmarks(1);
double cost1 = landmark.ComputeShortPath("1", "5");
//Console.WriteLine(cost1);
Console.WriteLine("******************************");
Console.ReadLine();
}