private void Run()
{
// direct all edges from the red nodes to the blue nodes
RedirectedGraph redToBlue = new RedirectedGraph(Graph,
x => (IsRed(Graph.U(x)) ? RedirectedGraph.Direction.Forward : RedirectedGraph.Direction.Backward));
// add a source and a target to the graph and some edges
Supergraph flowGraph = new Supergraph(redToBlue);
Node source = flowGraph.AddNode();
Node target = flowGraph.AddNode();
foreach (var node in Graph.Nodes())
{
if (IsRed(node))
{
flowGraph.AddArc(source, node, Directedness.Directed);
}
else
{
flowGraph.AddArc(node, target, Directedness.Directed);
}
}
Arc reflow = flowGraph.AddArc(target, source, Directedness.Directed);
// run the network simplex
NetworkSimplex ns = new NetworkSimplex(flowGraph,
lowerBound: x => (x == reflow ? MinimumMatchingSize : 0),
upperBound: x => (x == reflow ? MaximumMatchingSize : 1),
cost: x => (Graph.HasArc(x) ? Cost(x) : 0));
ns.Run();
if (ns.State == SimplexState.Optimal)
{
var matching = new Matching(Graph);
foreach (var arc in ns.UpperBoundArcs.Concat
(ns.Forest.Where(kv => kv.Value == 1).Select(kv => kv.Key)))
{
if (Graph.HasArc(arc))
{
matching.Enable(arc, true);
}
}
Matching = matching;
}
}
private void Run()
{
RedirectedGraph graph = new RedirectedGraph(Graph, (Arc x) => (!IsRed(Graph.U(x))) ? RedirectedGraph.Direction.Backward : RedirectedGraph.Direction.Forward);
Supergraph supergraph = new Supergraph(graph);
Node node = supergraph.AddNode();
Node node2 = supergraph.AddNode();
foreach (Node item in Graph.Nodes())
{
if (IsRed(item))
{
supergraph.AddArc(node, item, Directedness.Directed);
}
else
{
supergraph.AddArc(item, node2, Directedness.Directed);
}
}
Arc reflow = supergraph.AddArc(node2, node, Directedness.Directed);
NetworkSimplex networkSimplex = new NetworkSimplex(supergraph, (Arc x) => (x == reflow) ? MinimumMatchingSize : 0, (Arc x) => (!(x == reflow)) ? 1 : MaximumMatchingSize, null, (Arc x) => (!Graph.HasArc(x)) ? 0.0 : Cost(x));
networkSimplex.Run();
if (networkSimplex.State == SimplexState.Optimal)
{
Matching matching = new Matching(Graph);
foreach (Arc item2 in networkSimplex.UpperBoundArcs.Concat(from kv in networkSimplex.Forest
where kv.Value == 1
select kv.Key))
{
if (Graph.HasArc(item2))
{
matching.Enable(item2, true);
}
}
Matching = matching;
}
}