Class SzwarcfiterLauerSimpleCycles<V,E>

java.lang.Object
org.jgrapht.alg.cycle.SzwarcfiterLauerSimpleCycles<V,E>
Type Parameters:
V - the vertex type.
E - the edge type.
All Implemented Interfaces:
DirectedSimpleCycles<V,E>

public class SzwarcfiterLauerSimpleCycles<V,E> extends Object implements DirectedSimpleCycles<V,E>
Find all simple cycles of a directed graph using the Schwarcfiter and Lauer's algorithm.

See:
J.L.Szwarcfiter and P.E.Lauer, Finding the elementary cycles of a directed graph in $O(n + m)$ per cycle, Technical Report Series, #60, May 1974, Univ. of Newcastle upon Tyne, Newcastle upon Tyne, England.

  • Field Details

    • graph

      private Graph<V,E> graph
    • cycleConsumer

      private Consumer<List<V>> cycleConsumer
    • iToV

      private V[] iToV
    • vToI

      private Map<V,Integer> vToI
    • bSets

      private Map<V,Set<V>> bSets
    • stack

      private ArrayDeque<V> stack
    • marked

      private Set<V> marked
    • removed

      private Map<V,Set<V>> removed
    • position

      private int[] position
    • reach

      private boolean[] reach
    • startVertices

      private List<V> startVertices
  • Constructor Details

    • SzwarcfiterLauerSimpleCycles

      public SzwarcfiterLauerSimpleCycles()
      Create a simple cycle finder with an unspecified graph.
    • SzwarcfiterLauerSimpleCycles

      public SzwarcfiterLauerSimpleCycles(Graph<V,E> graph)
      Create a simple cycle finder for the specified graph.
      Parameters:
      graph - - the DirectedGraph in which to find cycles.
      Throws:
      IllegalArgumentException - if the graph argument is null.
  • Method Details

    • getGraph

      public Graph<V,E> getGraph()
      Get the graph
      Returns:
      graph
    • setGraph

      public void setGraph(Graph<V,E> graph)
      Set the graph
      Parameters:
      graph - graph
    • findSimpleCycles

      public void findSimpleCycles(Consumer<List<V>> consumer)
      Find the simple cycles of the graph.
      Specified by:
      findSimpleCycles in interface DirectedSimpleCycles<V,E>
      Parameters:
      consumer - Consumer that will be called with each cycle found.
    • cycle

      private boolean cycle(int v, int q)
    • noCycle

      private void noCycle(int x, int y)
    • unmark

      private void unmark(int x)
    • initState

      private void initState(Consumer<List<V>> consumer)
    • clearState

      private void clearState()
    • toI

      private Integer toI(V v)
    • toV

      private V toV(int i)
    • getBSet

      private Set<V> getBSet(V v)
    • getRemoved

      private Set<V> getRemoved(V v)