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How to get max_weight_matching in java


I have a Weighted and Non-Bipartite graph and would like to get the maximum weight matching. I have done the task with the python networkx library and looking for an alternative library for java. I looked into the JGraphT library but couldn't find the solution.

import networkx as nx
import networkx.algorithms.matching as matching

G=nx.Graph()

G.add_edge(1,2,weight = 30)
G.add_edge(1,3,weight = 100)
G.add_edge(1,4,weight = 30)
G.add_edge(2,3,weight = 0)
G.add_edge(2,4,weight = 30)
G.add_edge(3,4,weight = 30)
M = matching.max_weight_matching(G,maxcardinality=True)
print(list(M))
//OUTPUT: [(1, 3), (2, 4)]

Solution

  • Here's the solution using JGraphT:

    Graph<Integer, DefaultWeightedEdge> g = new SimpleWeightedGraph<>(SupplierUtil.createIntegerSupplier(1), SupplierUtil.createDefaultWeightedEdgeSupplier());
    Integer v1=g.addVertex();
    Integer v2=g.addVertex();
    Integer v3=g.addVertex();
    Integer v4=g.addVertex();
    
    Graphs.addEdge(g, v1, v2, 30);
    Graphs.addEdge(g, v1, v3, 100);
    Graphs.addEdge(g, v1, v4, 30);
    Graphs.addEdge(g, v2, v3, 0);
    Graphs.addEdge(g, v2, v4, 30);
    Graphs.addEdge(g, v3, v4, 30);
    
    MatchingAlgorithm<Integer, DefaultWeightedEdge> alg = new KolmogorovWeightedMatching<>(g, ObjectiveSense.MAXIMIZE);
    System.out.println(alg.getMatching());
    

    Output:

    Matching [edges=[(1 : 3), (2 : 4)], weight=130.0]