/// <summary>
/// Zwraca maksymalny las (maximal forest) w grafie
/// </summary>
static PartGraph Forest(PartGraph partGraph)
{
var graph = partGraph.Graph;
List <int> notVisited = new List <int>();
for (int i = 0; i < graph.VerticesCount; i++)
{
notVisited.Add(i);
}
HashSet <Edge> edges = new HashSet <Edge>();
while (notVisited.Count > 0)
{
int curNum = notVisited[0];
notVisited.Remove(curNum);
foreach (var edge in graph.OutEdges(curNum))
{
edges.Add(new Edge(partGraph.NumbersInOriginal[edge.From], partGraph.NumbersInOriginal[edge.To], edge.Weight));
notVisited.Remove(edge.To);
}
}
return(createPartGraphFromEdges(edges));
}
// Graf ma być spójny i nieskierowany
public static PartGraph Camerini(PartGraph partGraph)
{
var graph = partGraph.Graph;
var edges = getGraphEdges(partGraph);
if (edges.Count == 1)
{
return(partGraph);
}
// A - waga wieksza lub równa niż w B
(var A, var B) = setAandB(edges);
PartGraph GB = createPartGraphFromEdges(B);
var F = Forest(GB);
if (isSpanningTree(graph, F.Graph))
{
return(Camerini(GB));
}
else
{
var GA = createPartGraphFromEdges(A);
var CameriniforGA = Camerini(GA);
PartGraph ret = MergeGraphs(CameriniforGA, F);
return(ret);
}
}
static void printGraph(PartGraph GB, string comment)
{
Console.WriteLine($"Graph number: {++graphNum}");
Console.WriteLine(comment);
foreach (var x in GB.NumbersInOriginal)
{
Console.WriteLine($"{x.Key} : {x.Value}");
}
Console.WriteLine();
}
/// <summary>
/// Łączy dwa PartGrafy, zwracając PartGraf, będący sumą. Etykiety wierzchołków są zgodne z etykietami w oryginalnym grafie.
/// </summary>
static PartGraph MergeGraphs(PartGraph A, PartGraph B)
{
HashSet <Edge> edges = new HashSet <Edge>();
foreach (var e in getGraphEdges(A).ToArray())
{
edges.Add(e);
}
foreach (var e in getGraphEdges(B).ToArray())
{
edges.Add(e);
}
return(createPartGraphFromEdges(edges));
}
/// <summary>
/// Zwraca kolejkę krawędzi, oznaczonych numeracją grafu oryginalnego
/// </summary>
static EdgesMaxPriorityQueue getGraphEdges(PartGraph partGraph)
{
var graph = partGraph.Graph;
EdgesMaxPriorityQueue edges = new EdgesMaxPriorityQueue();
int verticesCount = graph.VerticesCount;
for (int i = 0; i < verticesCount; i++)
{
for (int j = 0; j < i; j++)
{
if (!double.IsNaN(graph.GetEdgeWeight(i, j)))
{
edges.Put(new Edge(partGraph.NumbersInOriginal[i], partGraph.NumbersInOriginal[j], graph.GetEdgeWeight(i, j)));
}
}
}
return(edges);
}
