public static IUnweightedDirectedGraph <TVertex> ToGraph <TVertex>(
this IEnumerable <IUnweightedEndpointPair <TVertex> > endpointPairs
)
{
var graph = new UnweightedDirectedGraph <TVertex>();
foreach (var endpointPair in endpointPairs)
{
graph.AddEdge(endpointPair.Origin, endpointPair.Destination);
}
return(graph);
}
public async Task <IUnweightedDirectedGraph <string> > GetUnweightedDirectedGraphAsync()
{
var edges = await EdgeService.GetEdgesAsync();
var graph = new UnweightedDirectedGraph <string>();
foreach (var edge in edges)
{
graph.AddEdge(edge.Origin, edge.Destination);
}
return(graph);
}
public static IUnweightedDirectedGraph <TVertex> DepthFirstSearch <TVertex>(
this IUnweightedDirectedGraph <TVertex> graph,
TVertex origin
)
{
if (graph == null)
{
throw new ArgumentNullException(nameof(graph));
}
if (origin == null)
{
throw new ArgumentNullException(nameof(origin));
}
if (!graph.Vertices.Contains(origin))
{
throw new ArgumentException();
}
var visited = new HashSet <TVertex>();
var output = new UnweightedDirectedGraph <TVertex>();
var stack = new Stack <TVertex>();
visited.Add(origin);
stack.Push(origin);
while (stack.Count > 0)
{
var vertex = stack.Pop();
bool Predicate(TVertex successorVertex)
{
return(!visited.Contains(successorVertex));
}
foreach (var successorVertex in graph.SuccessorVertices(vertex).Where(Predicate))
{
output.AddEdge(vertex, successorVertex);
visited.Add(successorVertex);
stack.Push(successorVertex);
}
}
return(output);
}
public void Test()
{
var g = new UnweightedDirectedGraph <string>();
g.AddVertex("a");
g.AddEdge(Edge <string> .Of("b", "c"));
g.AddEdge(Edge <string> .Of("b", "e"));
g.AddEdge(Edge <string> .Of("e", "f"));
g.AddEdge(Edge <string> .Of("f", "d"));
var node = g.NodeOf("c");
var node2 = g.NodeOf("f");
var allNodes = g.AllNodes();
var nbrs = g.Neighbors(Node <string> .Of("b")).ToList();
var incidentEdges = g.IncidentEdges(Node <string> .Of("b")).ToList();
var bfs = new BFS <string>(g);
var res = bfs.Execute("b");
var tmp = res;
}
private static void DoDebug()
{
#region Miscellaneous Algorithms
WriteLine("All Simple Paths - Default");
Stopwatch.Restart();
var allSimplePaths = WeightedDirectedGraph.AllSimplePaths(
"HARROW & WEALDSTONE",
"ELEPHANT & CASTLE",
EdgeAdder,
25
);
Stopwatch.Stop();
WriteLine($"Time: {Stopwatch.Elapsed}\n");
WriteLine("Breadth First Search - Default");
Stopwatch.Restart();
UnweightedDirectedGraph.BreadthFirstSearch(
"HARROW & WEALDSTONE"
);
Stopwatch.Stop();
WriteLine($"Time: {Stopwatch.Elapsed}\n");
WriteLine("Breadth First Search - Graph Enumerator");
Stopwatch.Restart();
new BreadthFirstSearchGraphEnumerator <string>(
UnweightedDirectedGraph,
"HARROW & WEALDSTONE"
).ToEnumerable();
Stopwatch.Stop();
WriteLine($"Time: {Stopwatch.Elapsed}\n");
WriteLine("Breadth First Search - Path Algorithm");
Stopwatch.Restart();
new BreadthFirstSearchUnweightedDirectedPathAlgorithm <string>(
UnweightedDirectedGraph
).PathCollection("HARROW & WEALDSTONE");
Stopwatch.Stop();
WriteLine($"Time: {Stopwatch.Elapsed}\n");
WriteLine("Depth First Search - Default");
Stopwatch.Restart();
UnweightedDirectedGraph.DepthFirstSearch(
"HARROW & WEALDSTONE"
);
Stopwatch.Stop();
WriteLine($"Time: {Stopwatch.Elapsed}\n");
WriteLine("Depth First Search - Graph Enumerator");
Stopwatch.Restart();
new DepthFirstSearchGraphEnumerator <string>(
UnweightedDirectedGraph,
"HARROW & WEALDSTONE"
).ToEnumerable();
Stopwatch.Stop();
WriteLine($"Time: {Stopwatch.Elapsed}\n");
WriteLine("Depth First Search - Path Algorithm");
Stopwatch.Restart();
new DepthFirstSearchUnweightedDirectedPathAlgorithm <string>(
UnweightedDirectedGraph
).PathCollection("HARROW & WEALDSTONE");
Stopwatch.Stop();
WriteLine($"Time: {Stopwatch.Elapsed}\n");
#endregion
#region Weighted Sum Algorithm
var allSimplePathsList = allSimplePaths.ToList();
var extremizeTypes = new Dictionary <ObjectiveType, ExtremizeType>
{
{ ObjectiveType.Time, ExtremizeType.Minimize },
{ ObjectiveType.Distance, ExtremizeType.Minimize },
{ ObjectiveType.Comfortability, ExtremizeType.Maximize },
{ ObjectiveType.Reliability, ExtremizeType.Maximize },
{ ObjectiveType.Connections, ExtremizeType.Minimize }
};
var weights = new Dictionary <ObjectiveType, double>
{
{ ObjectiveType.Comfortability, 100 },
{ ObjectiveType.Reliability, 50 }
};
WriteLine("Weighted Sum Shortest Path - Default");
Stopwatch.Restart();
allSimplePathsList.WeightedSumShortestPath(weights, WeightedSumShortestPathObjectiveSelector);
Stopwatch.Stop();
WriteLine($"Time: {Stopwatch.Elapsed}\n");
WriteLine("Weighted Sum Shortest Paths - Default");
Stopwatch.Restart();
allSimplePathsList.WeightedSumShortestPaths(extremizeTypes, WeightedSumShortestPathsObjectiveSelector);
Stopwatch.Stop();
WriteLine($"Time: {Stopwatch.Elapsed}\n");
#endregion
#region Dijkstra's Algorithm
EdgeComparer.NoOfTotalComparisons = 0;
EdgeComparer.NoOfInteractiveComparisons = 0;
WriteLine("Dijkstra Shortest Paths - Default");
Stopwatch.Restart();
WeightedDirectedGraph.DijkstraShortestPaths(
"HARROW & WEALDSTONE",
EdgeAdder,
EdgeComparer
);
Stopwatch.Stop();
WriteLine(
$"Time: {Stopwatch.Elapsed}, Interactive Comparisons: {EdgeComparer.NoOfInteractiveComparisons}, Total Comparisons: {EdgeComparer.NoOfTotalComparisons}\n"
);
EdgeComparer.NoOfTotalComparisons = 0;
EdgeComparer.NoOfInteractiveComparisons = 0;
WriteLine("Dijkstra Shortest Paths - Path Algorithm");
Stopwatch.Restart();
new DijkstraShortestWeightedDirectedPathAlgorithm <string, Edge>(
WeightedDirectedGraph,
EdgeAdder,
EdgeComparer
).PathCollection("HARROW & WEALDSTONE");
Stopwatch.Stop();
WriteLine(
$"Time: {Stopwatch.Elapsed}, Interactive Comparisons: {EdgeComparer.NoOfInteractiveComparisons}, Total Comparisons: {EdgeComparer.NoOfTotalComparisons}\n"
);
#endregion
}
