public void GraphSearchTest()
{
// this is the example graph at http://www.codeproject.com/cs/miscctrl/quickgraph.asp
Graph <BasicNode> g = new Graph <BasicNode>();
BasicNode u = new BasicNode("u");
BasicNode v = new BasicNode("v");
BasicNode w = new BasicNode("w");
BasicNode x = new BasicNode("x");
BasicNode y = new BasicNode("y");
BasicNode z = new BasicNode("z");
g.Nodes.Add(u);
g.Nodes.Add(v);
g.Nodes.Add(w);
g.Nodes.Add(x);
g.Nodes.Add(y);
g.Nodes.Add(z);
g.AddEdge(u, v);
g.AddEdge(u, x);
g.AddEdge(v, y);
g.AddEdge(y, x);
g.AddEdge(x, v);
g.AddEdge(w, u);
g.AddEdge(w, y);
g.AddEdge(w, z);
DepthFirstSearch <BasicNode> dfs = new DepthFirstSearch <BasicNode>(g);
dfs.DiscoverNode += delegate(BasicNode node) { Console.WriteLine("discover " + node); };
dfs.FinishNode += delegate(BasicNode node) { Console.WriteLine("finish " + node); };
dfs.DiscoverEdge += delegate(Edge <BasicNode> edge) { Console.WriteLine("discover " + edge); };
dfs.TreeEdge += delegate(Edge <BasicNode> edge) { Console.WriteLine("tree edge " + edge); };
dfs.FinishTreeEdge += delegate(Edge <BasicNode> edge) { Console.WriteLine("finish tree edge " + edge); };
dfs.CrossEdge += delegate(Edge <BasicNode> edge) { Console.WriteLine("cross edge " + edge); };
dfs.BackEdge += delegate(Edge <BasicNode> edge) { Console.WriteLine("back edge " + edge); };
Console.WriteLine("dfs from u:");
dfs.SearchFrom(u);
Console.WriteLine();
Console.WriteLine("dfs from w:");
dfs.SearchFrom(w);
Console.WriteLine();
dfs.Clear();
Console.WriteLine("cleared dfs from w:");
dfs.SearchFrom(w);
Console.WriteLine();
Console.WriteLine("bfs:");
BreadthFirstSearch <BasicNode> bfs = new BreadthFirstSearch <BasicNode>(g);
IndexedProperty <BasicNode, double> distance = g.CreateNodeData <double>(Double.PositiveInfinity);
bfs.DiscoverNode += delegate(BasicNode node) { Console.WriteLine("discover " + node); };
bfs.FinishNode += delegate(BasicNode node) { Console.WriteLine("finish " + node); };
bfs.TreeEdge += delegate(Edge <BasicNode> edge)
{
Console.WriteLine("tree edge " + edge);
distance[edge.Target] = distance[edge.Source] + 1;
};
// compute distances from w
distance[w] = 0;
bfs.SearchFrom(w);
Console.WriteLine("distances from w:");
foreach (BasicNode node in g.Nodes)
{
Console.WriteLine("[" + node + "] " + distance[node]);
}
Assert.Equal(2.0, distance[x]);
Console.WriteLine();
Console.WriteLine("distances from w:");
DistanceSearch <BasicNode> dists = new DistanceSearch <BasicNode>(g);
dists.SetDistance += delegate(BasicNode node, int dist) { Console.WriteLine("[" + node + "] " + dist); };
dists.SearchFrom(w);
Console.WriteLine();
BasicNode start = z, end;
(new PseudoPeripheralSearch <BasicNode>(g)).SearchFrom(ref start, out end);
Console.WriteLine("pseudo-peripheral nodes: " + start + "," + end);
StrongComponents <BasicNode> scc = new StrongComponents <BasicNode>(g);
int count = 0;
scc.AddNode += delegate(BasicNode node) { Console.Write(" " + node); };
scc.BeginComponent += delegate()
{
Console.Write("[");
count++;
};
scc.EndComponent += delegate() { Console.Write("]"); };
Console.Write("strong components reachable from w (topological order): ");
scc.SearchFrom(w);
Assert.Equal(4, count);
Console.WriteLine();
count = 0;
StrongComponents2 <BasicNode> scc2 = new StrongComponents2 <BasicNode>(g);
scc2.AddNode += delegate(BasicNode node) { Console.Write(" " + node); };
scc2.BeginComponent += delegate()
{
Console.Write("[");
count++;
};
scc2.EndComponent += delegate() { Console.Write("]"); };
Console.Write("strong components reachable from w (rev topological order): ");
scc2.SearchFrom(w);
Assert.Equal(4, count);
Console.WriteLine();
#if false
Console.WriteLine("CyclicDependencySort:");
List <BasicNode> schedule = CyclicDependencySort <BasicNode> .Schedule(g,
delegate(BasicNode node, ICollection <BasicNode> available) {
if (node == x)
{
return(available.Contains(u));
}
else
{
return(false);
}
},
g.Nodes);
foreach (BasicNode node in schedule)
{
Console.Write(node + " ");
}
Console.WriteLine();
Assert.Equal <int>(6, schedule.Count);
// order should be: w u x v y z (z can be re-ordered)
Assert.Equal <BasicNode>(w, schedule[0]);
Assert.Equal <BasicNode>(u, schedule[1]);
//Assert.Equal<BasicNode>(z,schedule[5]);
#endif
}
