public GraphNode DFSSearch(GraphNode startNode)
{
DFSNode node = new DFSNode(startNode);
DFSNode selectedNode = node;
int nCollectibles = 0;
Queue <DFSNode> frontier = new Queue <DFSNode>();
frontier.Enqueue(node);
while (true)
{
if (frontier.Count == 0)
{
break;
}
node = frontier.Dequeue();
if (node.GoalTest(nodesToVisit))
{
selectedNode = node;
break;
}
if (node.NumberCollectiblesCaught > nCollectibles)
{
nCollectibles = node.NumberCollectiblesCaught;
selectedNode = node;
}
List <GraphLink> adjacentLinks = node.Node.AdjacentNodes;
HashSet <GraphNode> adjNodes = new HashSet <GraphNode>();
foreach (GraphLink adjLink in adjacentLinks)
{
adjNodes.Add(adjLink.ToNode);
}
foreach (GraphNode adjNode in adjNodes)
{
frontier.Enqueue(new DFSNode(adjNode, node));
}
}
if (selectedNode.NodesPassed.Count > 1)
{
selectedNode.NodesPassed.Dequeue(); // remove startNode
return(selectedNode.NodesPassed.Dequeue());
}
else
{
return(null); // no path
}
}
public DFSNode(GraphNode node, DFSNode parent)
{
this.node = node;
nodesPassed = new Queue <GraphNode>(parent.NodesPassed);
if (!nodesPassed.Contains(this.Node))
{
nCollectibles = parent.NumberCollectiblesCaught + node.Platform.Collectibles.Count;
}
nodesPassed.Enqueue(this.node);
depth = parent.Depth + 1;
}