/// <summary>
/// Aplica algoritmo de Prim al grafo para hallar el MSP.
/// El Indentificador de los nodes tienen que ser de tipo int
/// </summary>
/// <param name="graph">Grafo</param>
/// <returns>El MSP</returns>
public static IEnumerable<IEdge> Run(IGraph graph)
{
int[] distancia = new int[graph.VertexList.Count];
IVertex[] phi = new IVertex[graph.VertexList.Count];
foreach (IVertex vertex in graph.VertexList)
{
distancia[(int) vertex.Identifier] = int.MaxValue;
phi[(int) vertex.Identifier] = null;
}
distancia[(int)graph.FirstVertex.Identifier] = 0;
var p_Queue = BinomialHeap<int>.Build_Heap(graph.VertexList, x => distancia[(int) x.Identifier]);
while (p_Queue.Count > 0)
{
var current = p_Queue.DeQueue();
foreach (IEdge edge in current.Out)
if (p_Queue.Contains(edge.Target) && edge.Cost < distancia[(int) edge.Target.Identifier])
{
distancia[(int) edge.Target.Identifier] = (int) edge.Cost;
phi[(int) edge.Target.Identifier] = edge.Source;
}
}
for (int i = 0; i < graph.VertexList.Count; i++)
{
yield return new EdgeResult(graph.VertexList[i], phi[i], distancia[i], false);
}
}
//<summary>
//Aplica algoritmo de Prim al grafo para hallar el MST.
//El Indentificador de los nodes tienen que ser de tipo int
//</summary>
//<param name="graph">Grafo</param>
//<returns>El MSP</returns>
public static IEnumerable Run(IGraph graph)
{
int[] distancia = new int[graph.Vertex_Count];
IVertex[] phi = new IVertex[graph.Vertex_Count];
foreach (IVertex vertex in graph.Vertexs)
{
distancia[vertex.Identifier] = int.MaxValue;
phi[vertex.Identifier] = null;
}
distancia[graph.Vertexs.First().Identifier] = 0;
var pQueue = BinomialHeap <IVertex> .Build_Heap(graph.Vertexs, x => distancia[x.Identifier]);
while (pQueue.Count > 0)
{
var current = pQueue.DeQueue();
foreach (IEdge edge in graph.Edg(current))
{
if (pQueue.Contains(edge.V_2) && edge.Cost < distancia[edge.V_2.Identifier])
{
distancia[edge.V_2.Identifier] = (int)edge.Cost;
phi[edge.V_2.Identifier] = edge.V_1;
}
}
}
var q = graph.Vertexs.ToArray();
for (int i = 0; i < q.Length; i++)
{
yield return(new { V_1 = q[i], V_2 = phi[i], Cost = distancia[i] });
}
}
private static HNode CreateHeap(IEnumerable <HNode> input)
{
var heap = BinomialHeap <HNode> .Build_Heap(input, x => x.Count); // O(n) amortized cost
while (heap.Count > 1)
{
var x = heap.DeQueue();
var y = heap.DeQueue();
heap.EnQueue(new HNode {
Left = x, Rigth = y, Key = char.Parse(" "), Count = x.Count + y.Count
}, x.Count + y.Count);
}
return(heap.DeQueue());
}