/// <summary>
/// returns true if graph contains given vertice false otherwise
/// </summary>
/// <param name="v"></param>
/// <returns></returns>
public bool Contains(Vertice v)
{
foreach (Vertice vert in Vertices)
if (vert.Equals(v))
return true;
return false;
}
/// <summary>
/// add edge to our graph
/// </summary>
/// <param name="e"></param>
public void AddEdge(Edge e)
{
if (this.Contains(e))
return;
Vertice v1 = new Vertice(e.v1);
Vertice v2 = new Vertice(e.v2);
if(!this.Contains(v1))
this.Vertices.Add(v1);
if(!this.Contains(v2))
this.Vertices.Add(v2);
this.Edges.Add(e);
}
/// <summary>
/// add vertice to our graph
/// </summary>
/// <param name="e"></param>
public void AddVertice(Vertice v)
{
if (this.Contains(v))
return;
this.Vertices.Add(v);
}
/// <summary>
/// returns sub graph neighbors vertices in super graph
/// </summary>
/// <param name="super"></param>
/// <param name="sub"></param>
/// <returns></returns>
public static List<Vertice> GetVerticesNeighborhood(Graph super, Graph sub,Vertice subVertice)
{
List<Vertice> nhood = new List<Vertice>();
foreach (Edge e in super.Edges)
if (subVertice.index == e.v1 && !sub.Contains(e))
{
nhood.Add(new Vertice(e.v2));
}
else if (subVertice.index == e.v2 && !sub.Contains(e))
{
nhood.Add(new Vertice(e.v1));
}
return nhood;
}
private static int GetTentativeDistance(Graph graph, Vertice v1, Vertice v2)
{
if (v1 == v2)
return 0;
if (graph.Contains(new Edge(v1.index, v2.index)))
return 1;
return int.MaxValue;
}
private static Graph GetPairGraph(Graph graph, Vertice u, Vertice v)
{
List<List<Vertice>> paths = GetDijkstraShortestPaths(graph, u);
List<Vertice> shortestPathUV = paths[v.index];
Graph pairUV = new Graph();
if (shortestPathUV != null)
{
foreach (Vertice current in shortestPathUV)
{
pairUV.Vertices.Add(current);
foreach (Edge edge in graph.Edges)
{
if (edge.v1 == current.index || edge.v2 == current.index)
{
pairUV.AddEdge(edge);
}
}
}
}
return pairUV;
}
//Dijkstra's shortest paths
public static List<List<Vertice>> GetDijkstraShortestPaths(Graph graph, Vertice vSource)
{
int[] distances = new int[graph.Vertices.Count];
bool[] visited = new bool[graph.Vertices.Count];
visited[vSource.index] = true;
foreach (Vertice vOuter in graph.Vertices)
distances[vOuter.index] = GetTentativeDistance(graph, vOuter, vSource);
while (true)
{
int iMin = GetMinimumUnvisitedIndex(distances, visited);
visited[iMin] = true;
foreach (Vertice vCurrent in graph.Vertices)
{
if (visited[vCurrent.index] == false)
{
if (GetTentativeDistance(graph, graph.Vertices[iMin], vCurrent) == int.MaxValue)
continue;
distances[vCurrent.index] = Math.Min(distances[iMin] + GetTentativeDistance(graph, graph.Vertices[iMin], vCurrent), distances[vCurrent.index]);
}
}
bool finished = true;
for (int i = 0; i < visited.Length; i++)
{
if (visited[i] == false && distances[i] != int.MaxValue)
{
finished = false;
break;
}
}
if (finished)
break;
}
var shortestPaths = new List<List<Vertice>>();
foreach (Vertice vCurrent in graph.Vertices)
{
Vertice vTemp = vCurrent;
shortestPaths.Add(new List<Vertice>());
shortestPaths[vCurrent.index].Insert(0, vCurrent);
if (distances[vCurrent.index] == int.MaxValue)
{
shortestPaths[vCurrent.index] = null;
continue;
}
if (vCurrent == vSource)
{
shortestPaths[vCurrent.index].Add(vSource);
continue;
}
while (true)
{
foreach (Edge eCurrent in graph.Edges)
{
if (eCurrent.v1 == vTemp.index && distances[eCurrent.v2] == distances[vTemp.index] - 1)
{
shortestPaths[vCurrent.index].Insert(0, graph.Vertices[eCurrent.v2]);
vTemp = graph.Vertices[eCurrent.v2];
break;
}
else if (eCurrent.v2 == vTemp.index && distances[eCurrent.v1] == distances[vTemp.index] - 1)
{
shortestPaths[vCurrent.index].Insert(0, graph.Vertices[eCurrent.v1]);
vTemp = graph.Vertices[eCurrent.v1];
break;
}
}
if (vTemp == vSource)
{
break;
}
}
}
return shortestPaths;
}
public static int GetCollaterialDistanceAndPairGraph(Graph graph, Vertice u, Vertice v, //Procedure 3.2
ref Graph pair)
{
Graph collaterial = GetCollaterialGraph(graph, new Edge(u.index, v.index));
List<List<Vertice>> shortestPathsU = GetDijkstraShortestPaths(collaterial, u);
List<List<Vertice>> shortestPathsV = GetDijkstraShortestPaths(collaterial, v);
pair = GetPairGraph(graph, u, v);
int collaterialUVDistance = shortestPathsU[graph.Vertices.IndexOf(v)].Count - 1;
return collaterialUVDistance;
}