public Prim(IGraph graph, Func <Arc, TCost> cost)
{
Graph = graph;
Cost = cost;
Forest = new HashSet <Arc>();
ForestGraph = new Subgraph(graph);
ForestGraph.EnableAllArcs(false);
Run();
}
/// Reverts the solver to its initial state.
public void Clear()
{
Dictionary <Node, long> excess = new Dictionary <Node, long>();
foreach (var n in Graph.Nodes())
{
excess[n] = Supply(n);
}
Saturated = new HashSet <Arc>();
foreach (var arc in Graph.Arcs())
{
long f = LowerBound(arc);
long g = UpperBound(arc);
if (g < long.MaxValue)
{
Saturated.Add(arc);
}
long flow = Flow(arc);
excess[Graph.U(arc)] -= flow;
excess[Graph.V(arc)] += flow;
}
Potential = new Dictionary <Node, double>();
MyGraph = new Supergraph(Graph);
ArtificialNode = MyGraph.AddNode();
Potential[ArtificialNode] = 0;
ArtificialArcs = new HashSet <Arc>();
var artificialArcOf = new Dictionary <Node, Arc>();
foreach (var n in Graph.Nodes())
{
long e = excess[n];
Arc arc = e > 0 ? MyGraph.AddArc(n, ArtificialNode, Directedness.Directed) :
MyGraph.AddArc(ArtificialNode, n, Directedness.Directed);
Potential[n] = (e > 0 ? -1 : 1);
ArtificialArcs.Add(arc);
artificialArcOf[n] = arc;
}
Tree = new Dictionary <Arc, long>();
TreeSubgraph = new Subgraph(MyGraph);
TreeSubgraph.EnableAllArcs(false);
foreach (var kv in artificialArcOf)
{
Tree[kv.Value] = Math.Abs(excess[kv.Key]);
TreeSubgraph.Enable(kv.Value, true);
}
State = SimplexState.FirstPhase;
EnteringArcEnumerator = MyGraph.Arcs().GetEnumerator();
EnteringArcEnumerator.MoveNext();
}
public void Clear()
{
Dictionary <Node, long> dictionary = new Dictionary <Node, long>();
foreach (Node item in Graph.Nodes())
{
dictionary[item] = Supply(item);
}
Saturated = new HashSet <Arc>();
foreach (Arc item2 in Graph.Arcs(ArcFilter.All))
{
LowerBound(item2);
long num = UpperBound(item2);
if (num < 9223372036854775807L)
{
Saturated.Add(item2);
}
long num2 = Flow(item2);
Node key;
Dictionary <Node, long> dictionary2;
(dictionary2 = dictionary)[key = Graph.U(item2)] = dictionary2[key] - num2;
Node key2;
(dictionary2 = dictionary)[key2 = Graph.V(item2)] = dictionary2[key2] + num2;
}
Potential = new Dictionary <Node, double>();
MyGraph = new Supergraph(Graph);
ArtificialNode = MyGraph.AddNode();
Potential[ArtificialNode] = 0.0;
ArtificialArcs = new HashSet <Arc>();
Dictionary <Node, Arc> dictionary3 = new Dictionary <Node, Arc>();
foreach (Node item3 in Graph.Nodes())
{
long num3 = dictionary[item3];
Arc arc = (num3 <= 0) ? MyGraph.AddArc(ArtificialNode, item3, Directedness.Directed) : MyGraph.AddArc(item3, ArtificialNode, Directedness.Directed);
Potential[item3] = (double)((num3 <= 0) ? 1 : (-1));
ArtificialArcs.Add(arc);
dictionary3[item3] = arc;
}
Tree = new Dictionary <Arc, long>();
TreeSubgraph = new Subgraph(MyGraph);
TreeSubgraph.EnableAllArcs(false);
foreach (KeyValuePair <Node, Arc> item4 in dictionary3)
{
Tree[item4.Value] = Math.Abs(dictionary[item4.Key]);
TreeSubgraph.Enable(item4.Value, true);
}
State = SimplexState.FirstPhase;
EnteringArcEnumerator = MyGraph.Arcs(ArcFilter.All).GetEnumerator();
EnteringArcEnumerator.MoveNext();
}
public BiEdgeConnectedComponents(IGraph graph, Flags flags = Flags.None)
{
Graph = graph;
BridgeDfs bridgeDfs = new BridgeDfs();
bridgeDfs.Run(graph, null);
Count = bridgeDfs.ComponentCount;
if ((flags & Flags.CreateBridges) != 0)
{
Bridges = bridgeDfs.Bridges;
}
if ((flags & Flags.CreateComponents) != 0)
{
Subgraph subgraph = new Subgraph(graph);
foreach (Arc bridge in bridgeDfs.Bridges)
{
subgraph.Enable(bridge, false);
}
Components = new ConnectedComponents(subgraph, ConnectedComponents.Flags.CreateComponents).Components;
}
}
private DisjointSet <Node> components; // The components of the current spanning forest.
public Kruskal(IGraph graph, Func <Arc, TCost> cost, Func <Node, int> maxDegree = null)
{
Graph = graph;
Cost = cost;
MaxDegree = maxDegree;
Forest = new HashSet <Arc>();
ForestGraph = new Subgraph(graph);
ForestGraph.EnableAllArcs(false);
Degree = new Dictionary <Node, int>();
foreach (var node in Graph.Nodes())
{
Degree[node] = 0;
}
List <Arc> arcs = Graph.Arcs().ToList();
arcs.Sort((a, b) => Cost(a).CompareTo(Cost(b)));
arcEnumerator = arcs.GetEnumerator();
arcsToGo = Graph.NodeCount() - new ConnectedComponents(Graph).Count;
components = new DisjointSet <Node>();
}
public BiEdgeConnectedComponents(IGraph graph, Flags flags = 0)
{
Graph = graph;
var dfs = new BridgeDfs();
dfs.Run(graph);
Count = dfs.ComponentCount;
if (0 != (flags & Flags.CreateBridges))
{
Bridges = dfs.Bridges;
}
if (0 != (flags & Flags.CreateComponents))
{
Subgraph withoutBridges = new Subgraph(graph);
foreach (var arc in dfs.Bridges)
{
withoutBridges.Enable(arc, false);
}
Components = new ConnectedComponents(withoutBridges, ConnectedComponents.Flags.CreateComponents).Components;
}
}
