org.jgrapht.alg

Class HopcroftKarpBipartiteMatching<V,E>

java.lang.Object

org.jgrapht.alg.HopcroftKarpBipartiteMatching<V,E>

Type Parameters:

V - the graph vertex type

E - the graph edge type

All Implemented Interfaces:

MatchingAlgorithm<V,E>

public class HopcroftKarpBipartiteMatching<V,E>
extends Object
implements MatchingAlgorithm<V,E>

This class is an implementation of the Hopcroft-Karp algorithm which finds a maximum matching in an undirected simple bipartite graph. The algorithm runs in O(|E|*√|V|) time. The original algorithm is described in: Hopcroft, John E.; Karp, Richard M. (1973), "An n5/2 algorithm for maximum matchings in bipartite graphs", SIAM Journal on Computing 2 (4): 225–231, doi:10.1137/0202019 A coarse overview of the algorithm is given in: http://en.wikipedia.org/wiki/Hopcroft-Karp_algorithm Note: the behavior of this class is undefined when the input isn't a bipartite graph, i.e. when there are edges within a single partition!

Author:

Joris Kinable

Constructor Summary

Constructors

Constructor and Description
HopcroftKarpBipartiteMatching(UndirectedGraph<V,E> graph, Set<V> partition1, Set<V> partition2) Create a new instance of the Hopcroft-Karp algorithm for the computation of maximum matchings in bipartite graphs.

Method Summary

Modifier and Type	Method and Description
Set<E>	getMatching() Returns set of edges making up the matching

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

HopcroftKarpBipartiteMatching

public HopcroftKarpBipartiteMatching(UndirectedGraph<V,E> graph,
                                     Set<V> partition1,
                                     Set<V> partition2)

Create a new instance of the Hopcroft-Karp algorithm for the computation of maximum matchings in bipartite graphs.

Parameters:

graph - the input graph

partition1 - vertex set of one of the partitions of the bipartite graph

partition2 - vertex set of the other partition of the bipartite graph

Method Detail

getMatching

public Set<E> getMatching()

Description copied from interface: MatchingAlgorithm

Returns set of edges making up the matching

Specified by:

getMatching in interface MatchingAlgorithm<V,E>

Returns:

a matching