Merge pull request #2 from matiii/priorityqueue

algorithm improved

Author: matiii

src/Dijkstra.NET/Dijkstra.NET.Benchmark/DijkstraBenchmarkBase.cs

@@ -29,8 +29,19 @@ public void Setup()
                 _graph.Connect((uint) node1, (uint) node2, (uint) cost, null);
             }
 
-            @from = (uint) random.Next(0, Nodes-1);
-            to = (uint) random.Next(0, Nodes-1);
+            _graph.Connect(0, 5, 10, null);
+            _graph.Connect(5, 121, 2, null);
+            _graph.Connect(121, 115, 1, null);
+            _graph.Connect(115, 300, 4, null);
+            _graph.Connect(300, 855, 2, null);
+            _graph.Connect(855, 1600, 1, null);
+            _graph.Connect(1600, 5000, 4, null);
+            _graph.Connect(5000, 50, 1, null);
+            _graph.Connect(50, 21, 1, null);
+            _graph.Connect(21, Nodes-1, 1, null);
+
+            @from = 0;
+            to = Nodes-1;
         }
     }
 }

src/Dijkstra.NET/Dijkstra.NET.Benchmark/Program.cs

@@ -7,7 +7,7 @@
 
     class Program
     {
-        static void Main(string[] args)
+        static void Main()
         {
             var normal = new  DijkstraBenchmark();
             normal.Setup();
@@ -16,7 +16,10 @@ static void Main(string[] args)
             DijkstraResult result = normal.GetPath();
             stopWatch.Stop();
 
-            Console.WriteLine($"Dijkstra takes {stopWatch.Elapsed.TotalSeconds:F} sec. Length of path is {result.GetPath().Count()}.");
+            uint[] path = result.GetPath().ToArray();
+
+            Console.WriteLine($"Dijkstra takes {stopWatch.ElapsedMilliseconds} ms. Length of path is {path.Length}.");
+            Console.WriteLine($"Path: {path.Select(x => x.ToString()).Aggregate((a, b) => a + " -> " + b)}");
 
             Console.ReadKey();
         }

src/Dijkstra.NET/Dijkstra.NET/Contract/IGraph.cs

@@ -2,7 +2,7 @@
 {
     using System.Collections.Generic;
 
-    public interface IGraph<T, TEdgeCustom> : IEnumerable<INode<T, TEdgeCustom>> where TEdgeCustom: class
+    public interface IGraph<T, TEdgeCustom> where TEdgeCustom: class
     {
         INode<T, TEdgeCustom> this[uint node] { get; }
     }

src/Dijkstra.NET/Dijkstra.NET/Dijkstra.cs

@@ -19,7 +19,7 @@ public DijkstraResult Process(uint from, uint to)
         {
             var result = new DijkstraResult(from, to);
             _graph[from].Distance = 0;
-            var q = new SortedSet<INode<T, TEdgeCustom>>(_graph, new NodeComparer<T, TEdgeCustom>());
+            var q = new SortedSet<INode<T, TEdgeCustom>>(new[] {_graph[from]}, new NodeComparer<T, TEdgeCustom>());
 
             while (q.Count > 0)
             {
@@ -37,7 +37,6 @@ public DijkstraResult Process(uint from, uint to)
 
                     if (e.Node.Distance > u.Distance + e.Cost)
                     {
-                        q.Remove(e.Node);
                         e.Node.Distance = u.Distance + e.Cost;
                         q.Add(e.Node);
                         result.Path[e.Node.Key] = u.Key;

src/Dijkstra.NET/Dijkstra.NET/Model/Graph.cs

@@ -5,7 +5,7 @@
     using System.Collections.Generic;
     using System.Linq;
     using Contract;
-    public class Graph<T, TEdgeCustom>: IGraph<T, TEdgeCustom>, ICloneable where TEdgeCustom: class 
+    public class Graph<T, TEdgeCustom>: IGraph<T, TEdgeCustom>, IEnumerable<INode<T, TEdgeCustom>>, ICloneable where TEdgeCustom: class 
     {
         private readonly IDictionary<uint, INode<T, TEdgeCustom>> _nodes = new Dictionary<uint, INode<T, TEdgeCustom>>();