private static void TestBFS()
{
Graph g = new Graph();
Vertex v1 = new Vertex();
Vertex v2 = new Vertex();
Vertex v3 = new Vertex();
Vertex v4 = new Vertex();
Vertex v5 = new Vertex();
Vertex v6 = new Vertex();
Vertex v7 = new Vertex();
g.AddVertex(v1);
g.AddVertex(v2);
g.AddVertex(v3);
g.AddVertex(v4);
g.AddVertex(v5);
g.AddVertex(v6);
g.AddVertex(v7);
g.AddEdge(new Edge(v1, v2));
g.AddEdge(new Edge(v1, v3));
g.AddEdge(new Edge(v2, v6));
g.AddEdge(new Edge(v2, v4));
g.AddEdge(new Edge(v6, v4));
g.AddEdge(new Edge(v4, v5));
List<Edge> path = GraphAlgorithms.BreadthFirstSearch(g, 0, 4);
}
public Vertex AddVertex()
{
checkNullGraph(currentGraph);
Vertex v = new Vertex();
currentGraph.AddVertex(v);
return v;
}
public FlowEdge AddFlowEdge(Vertex from, Vertex to)
{
checkNullGraph(currentGraph);
FlowEdge fe = new FlowEdge(from, to, 0, 1f);
currentGraph.AddEdge(fe);
return fe;
}
public FlowEdge(Vertex from, Vertex to, float currentFlow, float capacity)
: base(from, to)
{
Directed = true;
CurrentFlow = currentFlow;
Capacity = capacity;
}
public Edge AddEdge(Vertex from, Vertex to)
{
checkNullGraph(currentGraph);
Edge e = new Edge(from, to, 1f);
currentGraph.AddEdge(e);
return e;
}
private static void TestAllPairs()
{
//Graph for figure 4.15 part B
Graph g = new Graph();
Vertex v1 = new Vertex();
Vertex v2 = new Vertex();
Vertex v3 = new Vertex();
Vertex v4 = new Vertex();
Vertex v5 = new Vertex();
Vertex v6 = new Vertex();
Vertex v7 = new Vertex();
Vertex v8 = new Vertex();
Vertex v9 = new Vertex();
Vertex v10 = new Vertex();
Vertex v11 = new Vertex();
Vertex v12 = new Vertex();
g.AddVertex(v1);
g.AddVertex(v2);
g.AddVertex(v3);
g.AddVertex(v4);
g.AddVertex(v5);
g.AddVertex(v6);
g.AddVertex(v7);
g.AddVertex(v8);
g.AddVertex(v9);
g.AddVertex(v10);
g.AddVertex(v11);
g.AddVertex(v12);
g.AddEdge(new Edge(v1, v2, 5));
g.AddEdge(new Edge(v1, v4, 10));
g.AddEdge(new Edge(v2, v3, 7));
g.AddEdge(new Edge(v2, v5, 1));
g.AddEdge(new Edge(v3, v6, 4));
g.AddEdge(new Edge(v4, v5, 3));
g.AddEdge(new Edge(v5, v6, 3));
g.AddEdge(new Edge(v1, v2, 5));
g.AddEdge(new Edge(v4, v7, 11));
g.AddEdge(new Edge(v1, v2, 5));
g.AddEdge(new Edge(v5, v8, 7));
g.AddEdge(new Edge(v6, v9, 5));
g.AddEdge(new Edge(v7, v10, 9));
g.AddEdge(new Edge(v7, v8, 2));
g.AddEdge(new Edge(v8, v11, 1));
g.AddEdge(new Edge(v8, v9, 0));
g.AddEdge(new Edge(v9, v12, 12));
g.AddEdge(new Edge(v11, v12, 4));
float[,] d = GraphAlgorithms.AllPairsShortestPath(g);
GraphAlgorithms.PrintMatrix(d, g.GetVertices().Count);
}
public static Graph GenerateRandomGraph(int n)
{
float prob = 0.2f;
Graph g = new Graph();
g.Directed = false;
for (int i = 0; i < n; i++)
{
Vertex v = new Vertex();
g.AddVertex(v);
}
Random r = new Random();
//Randomly decide when to add an edge between any two pairs
foreach (Vertex v in g.GetVertices())
{
foreach (Vertex u in g.GetVertices())
{
if (!v.Equals(u))
{
double random = r.NextDouble();
if (random >= 0 && random <= prob)
{
g.AddEdge(new Edge(v, u, (float)r.NextDouble()));
}
}
}
}
foreach (Vertex v in g.GetVertices())
{
VertexClassification vc = ClassifyVertex(v);
Output.WriteLine("Vertex " + v.ToString() + " is " + vc.ToString());
}
return g;
}
public static VertexClassification ClassifyVertex(Vertex v)
{
int myDegree = v.GetTotalDegree();
List<Vertex> verts = v.GetAllNeighbors();
bool regular = true;
foreach (Vertex u in verts)
{
if (myDegree != u.GetTotalDegree())
{
regular = false;
break;
}
}
if (regular)
{
return VertexClassification.Regular;
}
bool veryStrong = true;
foreach (Vertex u in verts)
{
if (myDegree <= u.GetTotalDegree())
{
veryStrong = false;
break;
}
}
if (veryStrong)
{
return VertexClassification.VeryStrong;
}
bool strong = true;
foreach (Vertex u in verts)
{
if (myDegree < u.GetTotalDegree())
{
strong = false;
break;
}
}
if (strong)
{
return VertexClassification.Strong;
}
bool veryWeak = true;
foreach (Vertex u in verts)
{
if (myDegree >= u.GetTotalDegree())
{
veryWeak = false;
break;
}
}
if (veryWeak)
{
return VertexClassification.VeryWeak;
}
bool weak = true;
foreach (Vertex u in verts)
{
if (myDegree > u.GetTotalDegree())
{
weak = false;
break;
}
}
if (weak)
{
return VertexClassification.Weak;
}
return VertexClassification.Typical;
}
public void SetSource(Vertex s)
{
source = s;
}
private void copyLinkedGraph(Graph to)
{
to.Clear();
to.Directed = this.Directed;
for (int i = 0; i < this.GetVertices().Count; i++)
{
vertices[i].Tag = i;
Vertex v = new Vertex();
v.Tag = i;
to.AddVertex(v);
}
for (int i = this.GetEdges().Count-1; i >= 0; i--)
{
Edge currentEdge = this.GetEdges()[i];
Vertex v1 = new Vertex();
v1.Label = currentEdge.GetFromVertex().Label;
int cd = (int)currentEdge.GetFromVertex().Tag;
if ((int)to.GetVertices()[cd].Tag == cd)
{
v1 = to.GetVertices()[cd];
}
Vertex v2 = new Vertex();
v2.Label = currentEdge.GetToVertex().Label;
int cd2 = (int)currentEdge.GetToVertex().Tag;
if ((int)to.GetVertices()[cd2].Tag == cd2)
{
v2 = to.GetVertices()[cd2];
}
Edge e = currentEdge;
e = new Edge(v1, v2, currentEdge.Weight);
to.AddEdge(e);
}
}
public virtual void AddVertex(Vertex v)
{
v.SetGraph(this);
vertexCount++;
v.Label = vertexCount.ToString();
vertices.Add(v);
matrix.AddVertex();
}
private static void TestLabelCorrecting()
{
//Graph for figure 5.10 part A
Graph g = new Graph();
g.Directed = true;
Vertex v1 = new Vertex();
Vertex v2 = new Vertex();
Vertex v3 = new Vertex();
Vertex v4 = new Vertex();
Vertex v5 = new Vertex();
Vertex v6 = new Vertex();
g.AddEdge(new Edge(v1, v2, 10));
g.AddEdge(new Edge(v1, v3, 15));
g.AddEdge(new Edge(v2, v3, 25));
g.AddEdge(new Edge(v3, v2, -20));
g.AddEdge(new Edge(v2, v4, 0));
g.AddEdge(new Edge(v2, v5, 5));
g.AddEdge(new Edge(v4, v5, -5));
g.AddEdge(new Edge(v5, v4, 10));
g.AddEdge(new Edge(v5, v3, 30));
Console.WriteLine("Label Correcting Output:");
Graph labelCorrect = GraphAlgorithms.LabelCorrecting(g, 0);
}
private static void TestDominatingSets()
{
Graph g = new Graph();
g.Directed = false;
Vertex v1 = new Vertex();
Vertex v2 = new Vertex();
Vertex v3 = new Vertex();
Vertex v4 = new Vertex();
Vertex v5 = new Vertex();
Vertex v6 = new Vertex();
Vertex v7 = new Vertex();
g.AddEdge(new Edge(v1, v2));
g.AddEdge(new Edge(v2, v3));
g.AddEdge(new Edge(v3, v4));
g.AddEdge(new Edge(v4, v5));
g.AddEdge(new Edge(v5, v6));
g.AddEdge(new Edge(v6, v7));
//GraphAlgorithms.MinimumDominatingSet(g);
g.AddEdge(new Edge(v7, v1));
GraphAlgorithms.MinimumDominatingSet(g);
}
private static void TestDijkstra()
{
//Graph for figure 4.15 part A
Graph g = new Graph();
Vertex u1 = new Vertex();
Vertex u2 = new Vertex();
Vertex u3 = new Vertex();
Vertex u4 = new Vertex();
Vertex u5 = new Vertex();
Vertex u6 = new Vertex();
g.AddEdge(new Edge(u1, u2, 2));
g.AddEdge(new Edge(u1, u3, 8));
g.AddEdge(new Edge(u2, u3, 5));
g.AddEdge(new Edge(u2, u4, 3));
g.AddEdge(new Edge(u3, u2, 6));
g.AddEdge(new Edge(u3, u5, 0));
g.AddEdge(new Edge(u4, u3, 1));
g.AddEdge(new Edge(u4, u5, 7));
g.AddEdge(new Edge(u4, u6, 6));
g.AddEdge(new Edge(u5, u4, 4));
g.AddEdge(new Edge(u6, u5, 2));
Console.WriteLine("Dijkstra Output:");
Graph tree = GraphAlgorithms.Dijkstra(g, 0, true);
}
public bool RemoveVertex(Vertex v)
{
checkNullGraph(currentGraph);
currentGraph.RemoveVertex(v);
return true;
}
public static void MinimumDominatingSet(Graph g, int seed)
{
Output.WriteLine("[Minimum Dominating Set Output]");
//MDS takes an undirected graph
CombinationGenerator cg = new CombinationGenerator(g.GetVertices().Count, seed);
bool setFound = false;
List<Vertex> verts = new List<Vertex>(g.GetVertices().Count);
List<Vertex> neighborhood = new List<Vertex>();
List<Vertex[]> domSet = new List<Vertex[]>();
bool restricted = false;
int setLen = 0;
while (cg.HasNext())
{
int[] array = cg.GetNext();
int[] tally = new int[array.Length];
array.CopyTo(tally, 0);
Vertex[] possibleSet = new Vertex[cg.CurrentLevel()];
int possibleSetCounter = 0;
List<Vertex> neighbors = new List<Vertex>();
for (int i = 0; i < array.Length; i++)
{
if (array[i] != 1)
{
continue;
}
possibleSet[possibleSetCounter] = g.GetVertices()[i];
possibleSetCounter++;
neighbors.AddRange(g.GetVertices()[i].GetAllNeighbors());
}
foreach (Vertex v in neighbors)
{
int index = g.GetVertices().IndexOf(v);
if (index == -1)
{
continue;
}
tally[index] = 1;
}
bool validSet = true;
for (int i = 0; i < tally.Length; i++)
{
if (tally[i] != 1)
{
validSet = false;
break; //we break, because we only want to find one dominating set
}
}
if (validSet)
{
setFound = true;
if (!restricted)
{
cg.RestrictToCurrentLevel();
restricted = true;
setLen = possibleSet.Length;
}
if (setLen == possibleSet.Length)
{
domSet.Add(possibleSet);
break;
}
}
}
//Tally method
//Initiate tally to be the generated array, (create a copy!)
//go through the neighborhood of each vertex with value 1
//for each neighbor, change their value in the tally to 1
//If tally is all 1s, then you have everything
if (setFound)
{
//print out the found set and find the others
Output.WriteLine("Found minimum dominating sets:");
foreach (Vertex[] v in domSet)
{
string separator = "";
for (int i = 0; i < v.Length; i++)
{
Output.Write(separator + v[i].ToString());
separator = ",";
}
Output.WriteLine();
}
}
Output.WriteLine("[End Minimum Dominating Set Output]");
}
private static void TestMatrixStuff()
{
Graph g = new Graph();
g.Directed = true;
Vertex v1 = new Vertex();
Vertex v2 = new Vertex();
Vertex v3 = new Vertex();
Vertex v4 = new Vertex();
g.AddVertex(v1);
g.AddVertex(v2);
g.AddVertex(v3);
g.AddVertex(v4);
g.AddEdge(new Edge(v2, v1, 25f));
g.AddEdge(new Edge(v1, v3, 10f));
g.RemoveEdge(g.GetEdges()[1]);
g.AddEdge(new Edge(v4, v2, 7f));
g.RemoveVertex(v1);
g.RemoveVertex(v2);
g.AddEdge(new Edge(v3, v4, 30f));
g.AddEdge(new Edge(v4, v3, 27f));
Console.WriteLine("Testing graph insertion and deletion");
g.PrintMatrix();
Console.WriteLine();
Graph g2 = new Graph();
g.CopyTo(g2);
g2.PrintMatrix();
}
private static void TestMaxFlow()
{
FlowNetwork fn = new FlowNetwork();
Vertex v1 = new Vertex();
Vertex v2 = new Vertex();
Vertex v3 = new Vertex();
Vertex v4 = new Vertex();
Vertex v5 = new Vertex();
Vertex v6 = new Vertex();
fn.AddVertex(v1);
fn.AddVertex(v2);
fn.AddVertex(v3);
fn.AddVertex(v4);
fn.AddVertex(v5);
fn.AddVertex(v6);
fn.SetSource(v1);
fn.SetSink(v6);
fn.AddEdge(new FlowEdge(v1, v2, 0f, 2f));
fn.AddEdge(new FlowEdge(v1, v3, 0f, 2f));
fn.AddEdge(new FlowEdge(v2, v4, 0f, 2f));
fn.AddEdge(new FlowEdge(v3, v4, 1f, 2f));
fn.AddEdge(new FlowEdge(v3, v5, 0f, 2f));
fn.AddEdge(new FlowEdge(v4, v6, 1f, 2f));
fn.AddEdge(new FlowEdge(v5, v6, 0f, 2f));
//float maxFlow = GraphAlgorithms.MaximumFlow(fn);
//Console.WriteLine("Max flow is " + maxFlow);
}
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);
}
}
private static void TestResidualNetwork()
{
//Create graph from Figure 6.10
FlowNetwork fn = new FlowNetwork();
Vertex v1 = new Vertex();
Vertex v2 = new Vertex();
Vertex v3 = new Vertex();
Vertex v4 = new Vertex();
fn.AddVertex(v1);
fn.AddVertex(v2);
fn.AddVertex(v3);
fn.AddVertex(v4);
fn.SetSource(v1);
fn.SetSink(v4);
fn.AddEdge(new FlowEdge(v1, v3, 3, 4));
fn.AddEdge(new FlowEdge(v1, v2, 2, 2));
fn.AddEdge(new FlowEdge(v2, v3, 2, 3));
fn.AddEdge(new FlowEdge(v3, v4, 5, 5));
fn.AddEdge(new FlowEdge(v2, v4, 0, 1));
Graph g = GraphAlgorithms.CreateResidualNetwork(fn);
}
private void copyLinkedGraph(FlowNetwork to)
{
to.Clear();
for (int i = 0; i < this.GetVertices().Count; i++)
{
vertices[i].Tag = i;
Vertex v = new Vertex();
v.Tag = i;
to.AddVertex(v);
}
for (int i = 0; i < this.GetEdges().Count; i++)
{
Edge currentEdge = this.GetEdges()[i];
Vertex v1 = new Vertex();
v1.Label = currentEdge.GetFromVertex().Label;
int cd = (int)currentEdge.GetFromVertex().Tag;
if ((int)to.GetVertices()[cd].Tag == cd)
{
v1 = to.GetVertices()[cd];
}
Vertex v2 = new Vertex();
v2.Label = currentEdge.GetToVertex().Label;
int cd2 = (int)currentEdge.GetToVertex().Tag;
if ((int)to.GetVertices()[cd2].Tag == cd2)
{
v2 = to.GetVertices()[cd2];
}
FlowEdge fe = currentEdge as FlowEdge;
Edge e = new FlowEdge(v1, v2, fe.CurrentFlow, fe.Capacity);
to.AddEdge(e);
}
FlowNetwork fn = this as FlowNetwork;
if (fn != null)
{
to.SetSource(fn.GetSource());
to.SetSink(fn.GetSink());
}
}
public void SetSink(Vertex s)
{
sink = s;
}