private Subgraph FindSubgraph(Node node)
{
Subgraph subgraph = new Subgraph(graph);
AddReachable(node, subgraph);
return(subgraph);
}
/// <summary> Adds all nodes and edges reachable from this node to the subgraph.
/// Uses an explicit stack to avoid a large depth of recursion.
///
/// </summary>
/// <param name="node">a node known to be in the subgraph
/// </param>
private void AddReachable(Node startNode, Subgraph subgraph)
{
Stack nodeStack = new Stack();
nodeStack.Push(startNode);
while (!(nodeStack.Count == 0))
{
Node node = (Node)nodeStack.Pop();
AddEdges(node, nodeStack, subgraph);
}
}
/// <summary> Adds the argument node and all its out edges to the subgraph.</summary>
/// <param name="node">the node to add
/// </param>
/// <param name="nodeStack">the current set of nodes being traversed
/// </param>
private void AddEdges(Node node, Stack nodeStack, Subgraph subgraph)
{
node.Visited = true;
for (IEnumerator i = ((DirectedEdgeStar)node.OutEdges).Iterator();
i.MoveNext();)
{
DirectedEdge de = (DirectedEdge)i.Current;
subgraph.Add(de.Edge);
Node toNode = de.ToNode;
if (!toNode.Visited)
{
nodeStack.Push(toNode);
}
}
}