src/work/marci/max_bipartite_matching.h
author alpar
Thu, 22 Jul 2004 20:06:40 +0000
changeset 733 240003bddaff
parent 613 b5b5c4ae5107
child 762 511200bdb71f
permissions -rw-r--r--
Check StaticGraphSkeleton, as well.
     1 // -*- c++ -*-
     2 #ifndef HUGO_MAX_BIPARTITE_MATCHING_H
     3 #define HUGO_MAX_BIPARTITE_MATCHING_H
     4 
     5 /// \ingroup galgs
     6 /// \file
     7 /// \brief Maximum bipartite matchings, b-matchings and 
     8 /// capacitated b-matchings.
     9 ///
    10 /// This file contains a class for bipartite maximum matching, b-matchings 
    11 /// and capacitated b-matching computations.
    12 ///
    13 // /// \author Marton Makai
    14 
    15 //#include <for_each_macros.h>
    16 #include <bipartite_graph_wrapper.h>
    17 //#include <hugo/maps.h>
    18 #include <max_flow.h>
    19 
    20 namespace hugo {
    21 
    22   // template <typename Graph, typename EdgeCap, typename NodeCap, 
    23   // 	  typename EdgeFlow, typename NodeFlow>
    24   // class MaxMatching : public MaxFlow<stGraphWrapper<Graph>, 
    25   // 				   stGraphWrapper<Graph>:: EdgeMapWrapper<EdgeCan, NodeCap>, stGraphWrapper<Graph>::EdgeMapWrapper<EdgeFlow, NodeFlow> > {
    26   //   typedef MaxFlow<stGraphWrapper<Graph>, 
    27   // 		  stGraphWrapper<Graph>::EdgeMapWrapper<EdgeCan, NodeCap>, 
    28   // 		  stGraphWrapper<Graph>::EdgeMapWrapper<EdgeFlow, NodeFlow> >
    29   //   Parent;
    30   // protected:
    31   //   stGraphWrapper<Graph> gw;
    32   //   stGraphWrapper<Graph>::EdgeMapWrapper<EdgeCap, NodeCap> cap;
    33   //   stGraphWrapper<Graph>::EdgeMapWrapper<EdgeFlow, NodeFlow> flow;
    34   //   //graph* g;
    35   //   //EdgeCap* edge_cap;
    36   //   //EdgeFlow* edge_flow;
    37   // public:
    38   //   MaxMatching(Graph& _g, EdgeCap& _edge_cap, NodeCap& _node_cap, 
    39   // 	      EdgeFlow& _edge_flow, NodeFlow& _node_flow) : 
    40   //     MaxFlow(), gw(_g), 
    41   //     cap(_edge_cap, _node_cap), flow(_edge_flow, _node_flow) {
    42   //     Parent::set(gw, cap, flow);
    43   //   }
    44   // };
    45 
    46   /// \brief A bipartite matching class.
    47   ///
    48   /// This class reduces the matching problem to a flow problem and 
    49   /// a preflow is used on a wrapper. Such a generic approach means that 
    50   /// matchings, b-matchings an capacitated b-matchings can be handled in 
    51   /// a similar way. Due to the efficiency of the preflow algorithm, an 
    52   /// efficient matching framework is obtained.
    53   /// \ingroup galgs
    54   template <typename Graph, typename EdgeCap, typename NodeCap, 
    55 	    typename EdgeFlow, typename NodeFlow>
    56   class MaxBipartiteMatching {
    57   protected:
    58     //   EdgeCap* edge_cap;
    59     //   NodeCap* node_cap;
    60     //   EdgeFlow* edge_flow;
    61     //   NodeFlow* node_flow;
    62     typedef  stGraphWrapper<Graph> stGW;
    63     stGW stgw;
    64     typedef typename stGW::template EdgeMapWrapper<EdgeCap, NodeCap> CapMap; 
    65     CapMap cap;
    66     NodeFlow* node_flow;
    67     typedef typename stGW::template EdgeMapWrapper<EdgeFlow, NodeFlow> FlowMap;
    68     FlowMap flow;
    69     MaxFlow<stGW, int, CapMap, FlowMap> mf;
    70     //graph* g;
    71     //EdgeCap* edge_cap;
    72     //EdgeFlow* edge_flow;
    73   public:
    74     /// For capacitated b-matchings, edge-caoacities and node-capacities 
    75     /// have to be given. After running \c run the matching is is given 
    76     /// back in the edge-map \c _edge_flow and \c _node_map can be used 
    77     /// to obtain saturation information about nodes.
    78     ///\bug Note that the values in _edge_flow and _node_flow have 
    79     /// to form a flow.
    80     MaxBipartiteMatching(Graph& _g, EdgeCap& _edge_cap, NodeCap& _node_cap, 
    81 		EdgeFlow& _edge_flow, NodeFlow& _node_flow) : 
    82       stgw(_g), 
    83       cap(_edge_cap, _node_cap), 
    84       node_flow(0), 
    85       flow(_edge_flow, _node_flow), 
    86       mf(stgw, stgw.S_NODE, stgw.T_NODE, cap, flow) { }
    87     /// If the saturation information of nodes is not needed that the use of 
    88     /// this constructor is more comfortable.
    89     ///\bug Note that the values in _edge_flow and _node_flow have 
    90     /// to form a flow.
    91     MaxBipartiteMatching(Graph& _g, EdgeCap& _edge_cap, NodeCap& _node_cap, 
    92 		EdgeFlow& _edge_flow/*, NodeFlow& _node_flow*/) : 
    93       stgw(_g), 
    94       cap(_edge_cap, _node_cap), 
    95       node_flow(new NodeFlow(_g)), 
    96       flow(_edge_flow, *node_flow), 
    97       mf(stgw, stgw.S_NODE, stgw.T_NODE, cap, flow) { }
    98     /// The class have a nontrivial destructor.
    99     ~MaxBipartiteMatching() { if (node_flow) delete node_flow; }
   100     /// run computes the max matching.
   101     void run() { mf.run(); } 
   102     /// The matching value after running \c run.
   103     int matchingValue() { return mf.flowValue(); }
   104   };
   105 
   106 } //namespace hugo
   107 
   108 #endif //HUGO_MAX_BIPARTITE_MATCHING_H