public virtual void RemoveVertex(Vertex v)
{
int index = vertices.IndexOf(v);
bool success = vertices.Remove(v);
if (success)
{
vertexCount--;
v.SetGraph(null);
//Delete all edges going to and from this vertex
foreach (Edge e in v.GetInEdges())
{
RemoveEdge(e);
}
foreach (Edge e in v.GetOutEdges())
{
RemoveEdge(e);
}
matrix.RemoveVertex(index);
}
}
public virtual void RemoveVertex(Vertex v)
{
int index = vertices.IndexOf(v);
bool success = vertices.Remove(v);
if (success)
{
vertexCount--;
v.SetGraph(null);
//Delete all edges going to and from this vertex
foreach (Edge e in v.GetInEdges())
{
RemoveEdge(e);
}
foreach (Edge e in v.GetOutEdges())
{
RemoveEdge(e);
}
matrix.RemoveVertex(index);
}
}
public static List <Edge> BreadthFirstSearch(Graph g, int source, int goal)
{
//Does a breadth-first search and finds the shortest path between the source and the goal
//Returns null if no path exists
bool found = false;
bool directed = g.Directed;
List <object> tags = new List <object>();
List <Edge> path = new List <Edge>();
foreach (Vertex v in g.GetVertices())
{
tags.Add(v.Tag);
v.Tag = null;
}
Queue <Vertex> q = new Queue <Vertex>();
Vertex sourceVert = g.GetVertices()[source];
Vertex goalVert = g.GetVertices()[goal];
q.Enqueue(sourceVert);
sourceVert.Tag = new BFSData(null);
while (q.Count > 0)
{
Vertex next = q.Dequeue();
if (next.Equals(goalVert))
{
found = true;
break;
}
foreach (Edge e in next.GetOutEdges())
{
Vertex toVert = e.GetToVertex();
if (toVert.Tag != null)
{
continue;
}
else
{
toVert.Tag = e;
q.Enqueue(toVert);
}
}
if (!directed)
{
foreach (Edge e in next.GetInEdges())
{
Vertex toVert = e.GetFromVertex();
if (toVert.Tag != null)
{
continue;
}
else
{
toVert.Tag = e;
q.Enqueue(toVert);
}
}
}
}
if (!found)
{
return(null);
}
Edge currentEdge = goalVert.Tag as Edge;
path.Add(currentEdge);
while (!currentEdge.GetFromVertex().Equals(sourceVert))
{
Vertex nextVert = currentEdge.GetFromVertex();
currentEdge = nextVert.Tag as Edge;
path.Add(currentEdge);
}
path.Reverse();
for (int i = 0; i < tags.Count; i++)
{
g.GetVertices()[i].Tag = tags[i];
}
return(path);
}