// show shortest chain of relationships between name1 and name2
private static void ShowBingo(string name1, string name2)
{
GraphNode start = rg.GetNode(name1);
GraphNode end = rg.GetNode(name2);
// invalid case - start not in file
if (start == null)
{
Console.WriteLine("\t{0} not found", name1);
}
// invalid case - end not in file
else if (end == null)
{
Console.WriteLine("\t{0} not found", name2);
}
// invalid case - start is same as end
else if (start == end)
{
Console.WriteLine("\t{0} and {1} are the same", name1, name2);
}
// valid case - start and end are in file, and are different nodes
else
{
// list of nodes that will store the shortest path nodes
List <GraphNode> shortestPath = new List <GraphNode>();
// list of list of nodes that will store different paths from start to end
List <List <GraphNode> > paths = new List <List <GraphNode> >();
// list of nodes that will store the information of current depth nodes
List <GraphNode> currentDepth = new List <GraphNode>();
// dictionary to keep track of which nodes have been added and visited
Dictionary <string, bool> check = new Dictionary <string, bool>();
currentDepth.Add(start);
paths.Add(currentDepth);
int depthCount = 0;
while (true)
{
// new unique path
currentDepth = new List <GraphNode>();
// BFS
// for each node in the last path stored
foreach (GraphNode n in paths[paths.Count - 1])
{
// for each edge for the current node
foreach (GraphEdge e in n.GetEdges())
{
// if this edge leads to end, go to label
if (e.To() == end.GetName())
{
goto Found;
}
// otherwise update current path, and add it to our dictionary if not in there already
if (!check.ContainsKey(e.To()))
{
currentDepth.Add(e.ToNode());
check.Add(e.To(), true);
}
}
}
// add new unique path to list of paths
paths.Add(currentDepth);
}
Found:
shortestPath.Add(end);
depthCount = paths.Count - 1;
// while the last node in shortest path is not the same as start node, keep adding nodes to shortestPath list
// from end to start checking to see if they are in our paths list
while (shortestPath[shortestPath.Count - 1] != start && depthCount >= 0)
{
// for each edge of last node in shortest path
foreach (GraphEdge e in shortestPath[shortestPath.Count - 1].GetEdges())
{
if (paths[depthCount].Contains(e.ToNode()))
{
shortestPath.Add(e.ToNode());
goto NextLoop;
}
}
// for each node in this depth
foreach (GraphNode n in paths[depthCount])
{
foreach (GraphEdge e in n.GetEdges())
{
if (e.ToNode() == shortestPath[shortestPath.Count - 1])
{
shortestPath.Add(n);
goto NextLoop;
}
}
}
// decrement depthCount for next iteration
NextLoop:
depthCount--;
}
// reverse order shortestPath to get order from start to end, since it is in reverse order (end to start) right now
shortestPath.Reverse();
// output in line the relationship sentence for each edge in shortest path
for (int i = 1; i < shortestPath.Count; i++)
{
foreach (GraphEdge e in shortestPath[i - 1].GetEdges())
{
if (e.ToNode() == shortestPath[i])
{
Console.WriteLine("\t" + shortestPath[i - 1].GetName() + " is a " + e.Label.Substring(3).ToLower() + " of " + shortestPath[i].GetName());
}
}
}
}
}
