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/* -*- mode: C++; indent-tabs-mode: nil; -*- |
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* |
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* This file is a part of LEMON, a generic C++ optimization library. |
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* |
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* Copyright (C) 2003-2009 |
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* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
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* (Egervary Research Group on Combinatorial Optimization, EGRES). |
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* |
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* Permission to use, modify and distribute this software is granted |
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* provided that this copyright notice appears in all copies. For |
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* precise terms see the accompanying LICENSE file. |
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* |
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* This software is provided "AS IS" with no warranty of any kind, |
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* express or implied, and with no claim as to its suitability for any |
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* purpose. |
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* |
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*/ |
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#ifndef LEMON_FRACTIONAL_MATCHING_H |
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#define LEMON_FRACTIONAL_MATCHING_H |
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|
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#include <vector> |
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#include <queue> |
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#include <set> |
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#include <limits> |
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|
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#include <lemon/core.h> |
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#include <lemon/unionfind.h> |
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#include <lemon/bin_heap.h> |
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#include <lemon/maps.h> |
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#include <lemon/assert.h> |
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#include <lemon/elevator.h> |
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|
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///\ingroup matching |
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///\file |
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///\brief Fractional matching algorithms in general graphs. |
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|
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namespace lemon { |
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/// \brief Default traits class of MaxFractionalMatching class. |
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/// |
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/// Default traits class of MaxFractionalMatching class. |
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/// \tparam GR Graph type. |
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template <typename GR> |
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struct MaxFractionalMatchingDefaultTraits { |
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|
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/// \brief The type of the graph the algorithm runs on. |
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typedef GR Graph; |
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|
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/// \brief The type of the map that stores the matching. |
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/// |
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/// The type of the map that stores the matching arcs. |
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/// It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept. |
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typedef typename Graph::template NodeMap<typename GR::Arc> MatchingMap; |
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|
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/// \brief Instantiates a MatchingMap. |
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/// |
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/// This function instantiates a \ref MatchingMap. |
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/// \param graph The graph for which we would like to define |
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/// the matching map. |
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static MatchingMap* createMatchingMap(const Graph& graph) { |
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return new MatchingMap(graph); |
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} |
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|
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/// \brief The elevator type used by MaxFractionalMatching algorithm. |
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/// |
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/// The elevator type used by MaxFractionalMatching algorithm. |
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/// |
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/// \sa Elevator |
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/// \sa LinkedElevator |
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typedef LinkedElevator<Graph, typename Graph::Node> Elevator; |
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|
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/// \brief Instantiates an Elevator. |
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/// |
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/// This function instantiates an \ref Elevator. |
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/// \param graph The graph for which we would like to define |
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/// the elevator. |
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/// \param max_level The maximum level of the elevator. |
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static Elevator* createElevator(const Graph& graph, int max_level) { |
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return new Elevator(graph, max_level); |
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} |
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}; |
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|
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/// \ingroup matching |
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/// |
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/// \brief Max cardinality fractional matching |
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/// |
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/// This class provides an implementation of fractional matching |
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/// algorithm based on push-relabel principle. |
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/// |
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/// The maximum cardinality fractional matching is a relaxation of the |
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/// maximum cardinality matching problem where the odd set constraints |
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/// are omitted. |
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/// It can be formulated with the following linear program. |
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/// \f[ \sum_{e \in \delta(u)}x_e \le 1 \quad \forall u\in V\f] |
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/// \f[x_e \ge 0\quad \forall e\in E\f] |
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/// \f[\max \sum_{e\in E}x_e\f] |
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/// where \f$\delta(X)\f$ is the set of edges incident to a node in |
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/// \f$X\f$. The result can be represented as the union of a |
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/// matching with one value edges and a set of odd length cycles |
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/// with half value edges. |
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/// |
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/// The algorithm calculates an optimal fractional matching and a |
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/// barrier. The number of adjacents of any node set minus the size |
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/// of node set is a lower bound on the uncovered nodes in the |
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/// graph. For maximum matching a barrier is computed which |
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/// maximizes this difference. |
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/// |
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/// The algorithm can be executed with the run() function. After it |
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/// the matching (the primal solution) and the barrier (the dual |
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/// solution) can be obtained using the query functions. |
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/// |
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/// The primal solution is multiplied by |
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/// \ref MaxFractionalMatching::primalScale "2". |
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/// |
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/// \tparam GR The undirected graph type the algorithm runs on. |
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#ifdef DOXYGEN |
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template <typename GR, typename TR> |
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#else |
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template <typename GR, |
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typename TR = MaxFractionalMatchingDefaultTraits<GR> > |
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#endif |
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class MaxFractionalMatching { |
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public: |
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|
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/// \brief The \ref MaxFractionalMatchingDefaultTraits "traits |
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/// class" of the algorithm. |
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typedef TR Traits; |
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/// The type of the graph the algorithm runs on. |
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typedef typename TR::Graph Graph; |
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/// The type of the matching map. |
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typedef typename TR::MatchingMap MatchingMap; |
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/// The type of the elevator. |
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typedef typename TR::Elevator Elevator; |
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|
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/// \brief Scaling factor for primal solution |
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/// |
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/// Scaling factor for primal solution. |
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static const int primalScale = 2; |
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|
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private: |
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|
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const Graph &_graph; |
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int _node_num; |
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bool _allow_loops; |
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int _empty_level; |
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|
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TEMPLATE_GRAPH_TYPEDEFS(Graph); |
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|
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bool _local_matching; |
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MatchingMap *_matching; |
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|
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bool _local_level; |
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Elevator *_level; |
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|
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typedef typename Graph::template NodeMap<int> InDegMap; |
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InDegMap *_indeg; |
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|
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void createStructures() { |
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_node_num = countNodes(_graph); |
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|
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if (!_matching) { |
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_local_matching = true; |
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_matching = Traits::createMatchingMap(_graph); |
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} |
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if (!_level) { |
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_local_level = true; |
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_level = Traits::createElevator(_graph, _node_num); |
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} |
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if (!_indeg) { |
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_indeg = new InDegMap(_graph); |
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} |
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} |
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|
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void destroyStructures() { |
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if (_local_matching) { |
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delete _matching; |
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} |
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if (_local_level) { |
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delete _level; |
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} |
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if (_indeg) { |
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delete _indeg; |
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} |
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} |
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|
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void postprocessing() { |
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for (NodeIt n(_graph); n != INVALID; ++n) { |
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if ((*_indeg)[n] != 0) continue; |
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_indeg->set(n, -1); |
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Node u = n; |
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while ((*_matching)[u] != INVALID) { |
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Node v = _graph.target((*_matching)[u]); |
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_indeg->set(v, -1); |
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Arc a = _graph.oppositeArc((*_matching)[u]); |
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u = _graph.target((*_matching)[v]); |
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_indeg->set(u, -1); |
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_matching->set(v, a); |
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} |
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} |
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for (NodeIt n(_graph); n != INVALID; ++n) { |
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if ((*_indeg)[n] != 1) continue; |
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_indeg->set(n, -1); |
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|
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int num = 1; |
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Node u = _graph.target((*_matching)[n]); |
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while (u != n) { |
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_indeg->set(u, -1); |
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u = _graph.target((*_matching)[u]); |
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++num; |
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} |
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if (num % 2 == 0 && num > 2) { |
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Arc prev = _graph.oppositeArc((*_matching)[n]); |
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Node v = _graph.target((*_matching)[n]); |
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u = _graph.target((*_matching)[v]); |
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_matching->set(v, prev); |
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while (u != n) { |
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prev = _graph.oppositeArc((*_matching)[u]); |
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v = _graph.target((*_matching)[u]); |
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u = _graph.target((*_matching)[v]); |
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_matching->set(v, prev); |
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} |
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} |
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} |
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} |
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public: |
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typedef MaxFractionalMatching Create; |
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///\name Named Template Parameters |
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///@{ |
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template <typename T> |
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struct SetMatchingMapTraits : public Traits { |
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typedef T MatchingMap; |
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static MatchingMap *createMatchingMap(const Graph&) { |
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LEMON_ASSERT(false, "MatchingMap is not initialized"); |
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return 0; // ignore warnings |
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} |
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}; |
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/// \brief \ref named-templ-param "Named parameter" for setting |
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/// MatchingMap type |
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/// |
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/// \ref named-templ-param "Named parameter" for setting MatchingMap |
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/// type. |
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template <typename T> |
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struct SetMatchingMap |
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: public MaxFractionalMatching<Graph, SetMatchingMapTraits<T> > { |
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typedef MaxFractionalMatching<Graph, SetMatchingMapTraits<T> > Create; |
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}; |
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|
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template <typename T> |
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struct SetElevatorTraits : public Traits { |
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typedef T Elevator; |
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static Elevator *createElevator(const Graph&, int) { |
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LEMON_ASSERT(false, "Elevator is not initialized"); |
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return 0; // ignore warnings |
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} |
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}; |
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|
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/// \brief \ref named-templ-param "Named parameter" for setting |
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/// Elevator type |
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/// |
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/// \ref named-templ-param "Named parameter" for setting Elevator |
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/// type. If this named parameter is used, then an external |
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/// elevator object must be passed to the algorithm using the |
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/// \ref elevator(Elevator&) "elevator()" function before calling |
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/// \ref run() or \ref init(). |
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/// \sa SetStandardElevator |
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template <typename T> |
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struct SetElevator |
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: public MaxFractionalMatching<Graph, SetElevatorTraits<T> > { |
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typedef MaxFractionalMatching<Graph, SetElevatorTraits<T> > Create; |
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}; |
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|
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template <typename T> |
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struct SetStandardElevatorTraits : public Traits { |
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typedef T Elevator; |
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static Elevator *createElevator(const Graph& graph, int max_level) { |
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return new Elevator(graph, max_level); |
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} |
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}; |
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|
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/// \brief \ref named-templ-param "Named parameter" for setting |
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/// Elevator type with automatic allocation |
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/// |
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/// \ref named-templ-param "Named parameter" for setting Elevator |
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/// type with automatic allocation. |
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/// The Elevator should have standard constructor interface to be |
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/// able to automatically created by the algorithm (i.e. the |
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/// graph and the maximum level should be passed to it). |
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/// However an external elevator object could also be passed to the |
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/// algorithm with the \ref elevator(Elevator&) "elevator()" function |
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/// before calling \ref run() or \ref init(). |
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/// \sa SetElevator |
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template <typename T> |
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struct SetStandardElevator |
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: public MaxFractionalMatching<Graph, SetStandardElevatorTraits<T> > { |
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typedef MaxFractionalMatching<Graph, |
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SetStandardElevatorTraits<T> > Create; |
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}; |
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|
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/// @} |
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protected: |
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|
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MaxFractionalMatching() {} |
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public: |
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|
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/// \brief Constructor |
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/// |
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/// Constructor. |
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/// |
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MaxFractionalMatching(const Graph &graph, bool allow_loops = true) |
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: _graph(graph), _allow_loops(allow_loops), |
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_local_matching(false), _matching(0), |
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_local_level(false), _level(0), _indeg(0) |
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{} |
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|
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~MaxFractionalMatching() { |
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destroyStructures(); |
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} |
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|
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/// \brief Sets the matching map. |
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/// |
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/// Sets the matching map. |
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/// If you don't use this function before calling \ref run() or |
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/// \ref init(), an instance will be allocated automatically. |
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/// The destructor deallocates this automatically allocated map, |
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/// of course. |
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/// \return <tt>(*this)</tt> |
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MaxFractionalMatching& matchingMap(MatchingMap& map) { |
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if (_local_matching) { |
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delete _matching; |
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_local_matching = false; |
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} |
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_matching = ↦ |
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return *this; |
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} |
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|
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/// \brief Sets the elevator used by algorithm. |
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/// |
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/// Sets the elevator used by algorithm. |
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/// If you don't use this function before calling \ref run() or |
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/// \ref init(), an instance will be allocated automatically. |
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/// The destructor deallocates this automatically allocated elevator, |
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/// of course. |
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/// \return <tt>(*this)</tt> |
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MaxFractionalMatching& elevator(Elevator& elevator) { |
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if (_local_level) { |
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delete _level; |
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_local_level = false; |
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} |
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_level = &elevator; |
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return *this; |
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} |
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|
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/// \brief Returns a const reference to the elevator. |
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/// |
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/// Returns a const reference to the elevator. |
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/// |
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/// \pre Either \ref run() or \ref init() must be called before |
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/// using this function. |
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const Elevator& elevator() const { |
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return *_level; |
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} |
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|
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/// \name Execution control |
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/// The simplest way to execute the algorithm is to use one of the |
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/// member functions called \c run(). \n |
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/// If you need more control on the execution, first |
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377 |
/// you must call \ref init() and then one variant of the start() |
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/// member. |
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379 |
|
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/// @{ |
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381 |
|
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/// \brief Initializes the internal data structures. |
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383 |
/// |
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384 |
/// Initializes the internal data structures and sets the initial |
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/// matching. |
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386 |
void init() { |
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387 |
createStructures(); |
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388 |
|
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_level->initStart(); |
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for (NodeIt n(_graph); n != INVALID; ++n) { |
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_indeg->set(n, 0); |
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_matching->set(n, INVALID); |
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_level->initAddItem(n); |
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394 |
} |
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395 |
_level->initFinish(); |
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396 |
|
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397 |
_empty_level = _node_num; |
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398 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
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399 |
for (OutArcIt a(_graph, n); a != INVALID; ++a) { |
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400 |
if (_graph.target(a) == n && !_allow_loops) continue; |
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_matching->set(n, a); |
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Node v = _graph.target((*_matching)[n]); |
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_indeg->set(v, (*_indeg)[v] + 1); |
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break; |
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405 |
} |
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406 |
} |
|
407 |
|
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for (NodeIt n(_graph); n != INVALID; ++n) { |
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409 |
if ((*_indeg)[n] == 0) { |
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410 |
_level->activate(n); |
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411 |
} |
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412 |
} |
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413 |
} |
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414 |
|
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/// \brief Starts the algorithm and computes a fractional matching |
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/// |
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417 |
/// The algorithm computes a maximum fractional matching. |
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/// |
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/// \param postprocess The algorithm computes first a matching |
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/// which is a union of a matching with one value edges, cycles |
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/// with half value edges and even length paths with half value |
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/// edges. If the parameter is true, then after the push-relabel |
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/// algorithm it postprocesses the matching to contain only |
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424 |
/// matching edges and half value odd cycles. |
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425 |
void start(bool postprocess = true) { |
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426 |
Node n; |
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427 |
while ((n = _level->highestActive()) != INVALID) { |
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428 |
int level = _level->highestActiveLevel(); |
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429 |
int new_level = _level->maxLevel(); |
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430 |
for (InArcIt a(_graph, n); a != INVALID; ++a) { |
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431 |
Node u = _graph.source(a); |
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432 |
if (n == u && !_allow_loops) continue; |
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Node v = _graph.target((*_matching)[u]); |
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if ((*_level)[v] < level) { |
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435 |
_indeg->set(v, (*_indeg)[v] - 1); |
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436 |
if ((*_indeg)[v] == 0) { |
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_level->activate(v); |
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} |
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439 |
_matching->set(u, a); |
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_indeg->set(n, (*_indeg)[n] + 1); |
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_level->deactivate(n); |
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goto no_more_push; |
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443 |
} else if (new_level > (*_level)[v]) { |
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444 |
new_level = (*_level)[v]; |
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} |
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446 |
} |
|
447 |
|
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448 |
if (new_level + 1 < _level->maxLevel()) { |
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449 |
_level->liftHighestActive(new_level + 1); |
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450 |
} else { |
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451 |
_level->liftHighestActiveToTop(); |
|
452 |
} |
|
453 |
if (_level->emptyLevel(level)) { |
|
454 |
_level->liftToTop(level); |
|
455 |
} |
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456 |
no_more_push: |
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; |
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458 |
} |
|
459 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
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460 |
if ((*_matching)[n] == INVALID) continue; |
|
461 |
Node u = _graph.target((*_matching)[n]); |
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462 |
if ((*_indeg)[u] > 1) { |
|
463 |
_indeg->set(u, (*_indeg)[u] - 1); |
|
464 |
_matching->set(n, INVALID); |
|
465 |
} |
|
466 |
} |
|
467 |
if (postprocess) { |
|
468 |
postprocessing(); |
|
469 |
} |
|
470 |
} |
|
471 |
|
|
472 |
/// \brief Starts the algorithm and computes a perfect fractional |
|
473 |
/// matching |
|
474 |
/// |
|
475 |
/// The algorithm computes a perfect fractional matching. If it |
|
476 |
/// does not exists, then the algorithm returns false and the |
|
477 |
/// matching is undefined and the barrier. |
|
478 |
/// |
|
479 |
/// \param postprocess The algorithm computes first a matching |
|
480 |
/// which is a union of a matching with one value edges, cycles |
|
481 |
/// with half value edges and even length paths with half value |
|
482 |
/// edges. If the parameter is true, then after the push-relabel |
|
483 |
/// algorithm it postprocesses the matching to contain only |
|
484 |
/// matching edges and half value odd cycles. |
|
485 |
bool startPerfect(bool postprocess = true) { |
|
486 |
Node n; |
|
487 |
while ((n = _level->highestActive()) != INVALID) { |
|
488 |
int level = _level->highestActiveLevel(); |
|
489 |
int new_level = _level->maxLevel(); |
|
490 |
for (InArcIt a(_graph, n); a != INVALID; ++a) { |
|
491 |
Node u = _graph.source(a); |
|
492 |
if (n == u && !_allow_loops) continue; |
|
493 |
Node v = _graph.target((*_matching)[u]); |
|
494 |
if ((*_level)[v] < level) { |
|
495 |
_indeg->set(v, (*_indeg)[v] - 1); |
|
496 |
if ((*_indeg)[v] == 0) { |
|
497 |
_level->activate(v); |
|
498 |
} |
|
499 |
_matching->set(u, a); |
|
500 |
_indeg->set(n, (*_indeg)[n] + 1); |
|
501 |
_level->deactivate(n); |
|
502 |
goto no_more_push; |
|
503 |
} else if (new_level > (*_level)[v]) { |
|
504 |
new_level = (*_level)[v]; |
|
505 |
} |
|
506 |
} |
|
507 |
|
|
508 |
if (new_level + 1 < _level->maxLevel()) { |
|
509 |
_level->liftHighestActive(new_level + 1); |
|
510 |
} else { |
|
511 |
_level->liftHighestActiveToTop(); |
|
512 |
_empty_level = _level->maxLevel() - 1; |
|
513 |
return false; |
|
514 |
} |
|
515 |
if (_level->emptyLevel(level)) { |
|
516 |
_level->liftToTop(level); |
|
517 |
_empty_level = level; |
|
518 |
return false; |
|
519 |
} |
|
520 |
no_more_push: |
|
521 |
; |
|
522 |
} |
|
523 |
if (postprocess) { |
|
524 |
postprocessing(); |
|
525 |
} |
|
526 |
return true; |
|
527 |
} |
|
528 |
|
|
529 |
/// \brief Runs the algorithm |
|
530 |
/// |
|
531 |
/// Just a shortcut for the next code: |
|
532 |
///\code |
|
533 |
/// init(); |
|
534 |
/// start(); |
|
535 |
///\endcode |
|
536 |
void run(bool postprocess = true) { |
|
537 |
init(); |
|
538 |
start(postprocess); |
|
539 |
} |
|
540 |
|
|
541 |
/// \brief Runs the algorithm to find a perfect fractional matching |
|
542 |
/// |
|
543 |
/// Just a shortcut for the next code: |
|
544 |
///\code |
|
545 |
/// init(); |
|
546 |
/// startPerfect(); |
|
547 |
///\endcode |
|
548 |
bool runPerfect(bool postprocess = true) { |
|
549 |
init(); |
|
550 |
return startPerfect(postprocess); |
|
551 |
} |
|
552 |
|
|
553 |
///@} |
|
554 |
|
|
555 |
/// \name Query Functions |
|
556 |
/// The result of the %Matching algorithm can be obtained using these |
|
557 |
/// functions.\n |
|
558 |
/// Before the use of these functions, |
|
559 |
/// either run() or start() must be called. |
|
560 |
///@{ |
|
561 |
|
|
562 |
|
|
563 |
/// \brief Return the number of covered nodes in the matching. |
|
564 |
/// |
|
565 |
/// This function returns the number of covered nodes in the matching. |
|
566 |
/// |
|
567 |
/// \pre Either run() or start() must be called before using this function. |
|
568 |
int matchingSize() const { |
|
569 |
int num = 0; |
|
570 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
571 |
if ((*_matching)[n] != INVALID) { |
|
572 |
++num; |
|
573 |
} |
|
574 |
} |
|
575 |
return num; |
|
576 |
} |
|
577 |
|
|
578 |
/// \brief Returns a const reference to the matching map. |
|
579 |
/// |
|
580 |
/// Returns a const reference to the node map storing the found |
|
581 |
/// fractional matching. This method can be called after |
|
582 |
/// running the algorithm. |
|
583 |
/// |
|
584 |
/// \pre Either \ref run() or \ref init() must be called before |
|
585 |
/// using this function. |
|
586 |
const MatchingMap& matchingMap() const { |
|
587 |
return *_matching; |
|
588 |
} |
|
589 |
|
|
590 |
/// \brief Return \c true if the given edge is in the matching. |
|
591 |
/// |
|
592 |
/// This function returns \c true if the given edge is in the |
|
593 |
/// found matching. The result is scaled by \ref primalScale |
|
594 |
/// "primal scale". |
|
595 |
/// |
|
596 |
/// \pre Either run() or start() must be called before using this function. |
|
597 |
int matching(const Edge& edge) const { |
|
598 |
return (edge == (*_matching)[_graph.u(edge)] ? 1 : 0) + |
|
599 |
(edge == (*_matching)[_graph.v(edge)] ? 1 : 0); |
|
600 |
} |
|
601 |
|
|
602 |
/// \brief Return the fractional matching arc (or edge) incident |
|
603 |
/// to the given node. |
|
604 |
/// |
|
605 |
/// This function returns one of the fractional matching arc (or |
|
606 |
/// edge) incident to the given node in the found matching or \c |
|
607 |
/// INVALID if the node is not covered by the matching or if the |
|
608 |
/// node is on an odd length cycle then it is the successor edge |
|
609 |
/// on the cycle. |
|
610 |
/// |
|
611 |
/// \pre Either run() or start() must be called before using this function. |
|
612 |
Arc matching(const Node& node) const { |
|
613 |
return (*_matching)[node]; |
|
614 |
} |
|
615 |
|
|
616 |
/// \brief Returns true if the node is in the barrier |
|
617 |
/// |
|
618 |
/// The barrier is a subset of the nodes. If the nodes in the |
|
619 |
/// barrier have less adjacent nodes than the size of the barrier, |
|
620 |
/// then at least as much nodes cannot be covered as the |
|
621 |
/// difference of the two subsets. |
|
622 |
bool barrier(const Node& node) const { |
|
623 |
return (*_level)[node] >= _empty_level; |
|
624 |
} |
|
625 |
|
|
626 |
/// @} |
|
627 |
|
|
628 |
}; |
|
629 |
|
|
630 |
/// \ingroup matching |
|
631 |
/// |
|
632 |
/// \brief Weighted fractional matching in general graphs |
|
633 |
/// |
|
634 |
/// This class provides an efficient implementation of fractional |
|
635 |
/// matching algorithm. The implementation uses priority queues and |
|
636 |
/// provides \f$O(nm\log n)\f$ time complexity. |
|
637 |
/// |
|
638 |
/// The maximum weighted fractional matching is a relaxation of the |
|
639 |
/// maximum weighted matching problem where the odd set constraints |
|
640 |
/// are omitted. |
|
641 |
/// It can be formulated with the following linear program. |
|
642 |
/// \f[ \sum_{e \in \delta(u)}x_e \le 1 \quad \forall u\in V\f] |
|
643 |
/// \f[x_e \ge 0\quad \forall e\in E\f] |
|
644 |
/// \f[\max \sum_{e\in E}x_ew_e\f] |
|
645 |
/// where \f$\delta(X)\f$ is the set of edges incident to a node in |
|
646 |
/// \f$X\f$. The result must be the union of a matching with one |
|
647 |
/// value edges and a set of odd length cycles with half value edges. |
|
648 |
/// |
|
649 |
/// The algorithm calculates an optimal fractional matching and a |
|
650 |
/// proof of the optimality. The solution of the dual problem can be |
|
651 |
/// used to check the result of the algorithm. The dual linear |
|
652 |
/// problem is the following. |
|
653 |
/// \f[ y_u + y_v \ge w_{uv} \quad \forall uv\in E\f] |
|
654 |
/// \f[y_u \ge 0 \quad \forall u \in V\f] |
|
655 |
/// \f[\min \sum_{u \in V}y_u \f] |
|
656 |
/// |
|
657 |
/// The algorithm can be executed with the run() function. |
|
658 |
/// After it the matching (the primal solution) and the dual solution |
|
659 |
/// can be obtained using the query functions. |
|
660 |
/// |
|
661 |
/// The primal solution is multiplied by |
|
662 |
/// \ref MaxWeightedFractionalMatching::primalScale "2". |
|
663 |
/// If the value type is integer, then the dual |
|
664 |
/// solution is scaled by |
|
665 |
/// \ref MaxWeightedFractionalMatching::dualScale "4". |
|
666 |
/// |
|
667 |
/// \tparam GR The undirected graph type the algorithm runs on. |
|
668 |
/// \tparam WM The type edge weight map. The default type is |
|
669 |
/// \ref concepts::Graph::EdgeMap "GR::EdgeMap<int>". |
|
670 |
#ifdef DOXYGEN |
|
671 |
template <typename GR, typename WM> |
|
672 |
#else |
|
673 |
template <typename GR, |
|
674 |
typename WM = typename GR::template EdgeMap<int> > |
|
675 |
#endif |
|
676 |
class MaxWeightedFractionalMatching { |
|
677 |
public: |
|
678 |
|
|
679 |
/// The graph type of the algorithm |
|
680 |
typedef GR Graph; |
|
681 |
/// The type of the edge weight map |
|
682 |
typedef WM WeightMap; |
|
683 |
/// The value type of the edge weights |
|
684 |
typedef typename WeightMap::Value Value; |
|
685 |
|
|
686 |
/// The type of the matching map |
|
687 |
typedef typename Graph::template NodeMap<typename Graph::Arc> |
|
688 |
MatchingMap; |
|
689 |
|
|
690 |
/// \brief Scaling factor for primal solution |
|
691 |
/// |
|
692 |
/// Scaling factor for primal solution. |
|
693 |
static const int primalScale = 2; |
|
694 |
|
|
695 |
/// \brief Scaling factor for dual solution |
|
696 |
/// |
|
697 |
/// Scaling factor for dual solution. It is equal to 4 or 1 |
|
698 |
/// according to the value type. |
|
699 |
static const int dualScale = |
|
700 |
std::numeric_limits<Value>::is_integer ? 4 : 1; |
|
701 |
|
|
702 |
private: |
|
703 |
|
|
704 |
TEMPLATE_GRAPH_TYPEDEFS(Graph); |
|
705 |
|
|
706 |
typedef typename Graph::template NodeMap<Value> NodePotential; |
|
707 |
|
|
708 |
const Graph& _graph; |
|
709 |
const WeightMap& _weight; |
|
710 |
|
|
711 |
MatchingMap* _matching; |
|
712 |
NodePotential* _node_potential; |
|
713 |
|
|
714 |
int _node_num; |
|
715 |
bool _allow_loops; |
|
716 |
|
|
717 |
enum Status { |
|
718 |
EVEN = -1, MATCHED = 0, ODD = 1 |
|
719 |
}; |
|
720 |
|
|
721 |
typedef typename Graph::template NodeMap<Status> StatusMap; |
|
722 |
StatusMap* _status; |
|
723 |
|
|
724 |
typedef typename Graph::template NodeMap<Arc> PredMap; |
|
725 |
PredMap* _pred; |
|
726 |
|
|
727 |
typedef ExtendFindEnum<IntNodeMap> TreeSet; |
|
728 |
|
|
729 |
IntNodeMap *_tree_set_index; |
|
730 |
TreeSet *_tree_set; |
|
731 |
|
|
732 |
IntNodeMap *_delta1_index; |
|
733 |
BinHeap<Value, IntNodeMap> *_delta1; |
|
734 |
|
|
735 |
IntNodeMap *_delta2_index; |
|
736 |
BinHeap<Value, IntNodeMap> *_delta2; |
|
737 |
|
|
738 |
IntEdgeMap *_delta3_index; |
|
739 |
BinHeap<Value, IntEdgeMap> *_delta3; |
|
740 |
|
|
741 |
Value _delta_sum; |
|
742 |
|
|
743 |
void createStructures() { |
|
744 |
_node_num = countNodes(_graph); |
|
745 |
|
|
746 |
if (!_matching) { |
|
747 |
_matching = new MatchingMap(_graph); |
|
748 |
} |
|
749 |
if (!_node_potential) { |
|
750 |
_node_potential = new NodePotential(_graph); |
|
751 |
} |
|
752 |
if (!_status) { |
|
753 |
_status = new StatusMap(_graph); |
|
754 |
} |
|
755 |
if (!_pred) { |
|
756 |
_pred = new PredMap(_graph); |
|
757 |
} |
|
758 |
if (!_tree_set) { |
|
759 |
_tree_set_index = new IntNodeMap(_graph); |
|
760 |
_tree_set = new TreeSet(*_tree_set_index); |
|
761 |
} |
|
762 |
if (!_delta1) { |
|
763 |
_delta1_index = new IntNodeMap(_graph); |
|
764 |
_delta1 = new BinHeap<Value, IntNodeMap>(*_delta1_index); |
|
765 |
} |
|
766 |
if (!_delta2) { |
|
767 |
_delta2_index = new IntNodeMap(_graph); |
|
768 |
_delta2 = new BinHeap<Value, IntNodeMap>(*_delta2_index); |
|
769 |
} |
|
770 |
if (!_delta3) { |
|
771 |
_delta3_index = new IntEdgeMap(_graph); |
|
772 |
_delta3 = new BinHeap<Value, IntEdgeMap>(*_delta3_index); |
|
773 |
} |
|
774 |
} |
|
775 |
|
|
776 |
void destroyStructures() { |
|
777 |
if (_matching) { |
|
778 |
delete _matching; |
|
779 |
} |
|
780 |
if (_node_potential) { |
|
781 |
delete _node_potential; |
|
782 |
} |
|
783 |
if (_status) { |
|
784 |
delete _status; |
|
785 |
} |
|
786 |
if (_pred) { |
|
787 |
delete _pred; |
|
788 |
} |
|
789 |
if (_tree_set) { |
|
790 |
delete _tree_set_index; |
|
791 |
delete _tree_set; |
|
792 |
} |
|
793 |
if (_delta1) { |
|
794 |
delete _delta1_index; |
|
795 |
delete _delta1; |
|
796 |
} |
|
797 |
if (_delta2) { |
|
798 |
delete _delta2_index; |
|
799 |
delete _delta2; |
|
800 |
} |
|
801 |
if (_delta3) { |
|
802 |
delete _delta3_index; |
|
803 |
delete _delta3; |
|
804 |
} |
|
805 |
} |
|
806 |
|
|
807 |
void matchedToEven(Node node, int tree) { |
|
808 |
_tree_set->insert(node, tree); |
|
809 |
_node_potential->set(node, (*_node_potential)[node] + _delta_sum); |
|
810 |
_delta1->push(node, (*_node_potential)[node]); |
|
811 |
|
|
812 |
if (_delta2->state(node) == _delta2->IN_HEAP) { |
|
813 |
_delta2->erase(node); |
|
814 |
} |
|
815 |
|
|
816 |
for (InArcIt a(_graph, node); a != INVALID; ++a) { |
|
817 |
Node v = _graph.source(a); |
|
818 |
Value rw = (*_node_potential)[node] + (*_node_potential)[v] - |
|
819 |
dualScale * _weight[a]; |
|
820 |
if (node == v) { |
|
821 |
if (_allow_loops && _graph.direction(a)) { |
|
822 |
_delta3->push(a, rw / 2); |
|
823 |
} |
|
824 |
} else if ((*_status)[v] == EVEN) { |
|
825 |
_delta3->push(a, rw / 2); |
|
826 |
} else if ((*_status)[v] == MATCHED) { |
|
827 |
if (_delta2->state(v) != _delta2->IN_HEAP) { |
|
828 |
_pred->set(v, a); |
|
829 |
_delta2->push(v, rw); |
|
830 |
} else if ((*_delta2)[v] > rw) { |
|
831 |
_pred->set(v, a); |
|
832 |
_delta2->decrease(v, rw); |
|
833 |
} |
|
834 |
} |
|
835 |
} |
|
836 |
} |
|
837 |
|
|
838 |
void matchedToOdd(Node node, int tree) { |
|
839 |
_tree_set->insert(node, tree); |
|
840 |
_node_potential->set(node, (*_node_potential)[node] - _delta_sum); |
|
841 |
|
|
842 |
if (_delta2->state(node) == _delta2->IN_HEAP) { |
|
843 |
_delta2->erase(node); |
|
844 |
} |
|
845 |
} |
|
846 |
|
|
847 |
void evenToMatched(Node node, int tree) { |
|
848 |
_delta1->erase(node); |
|
849 |
_node_potential->set(node, (*_node_potential)[node] - _delta_sum); |
|
850 |
Arc min = INVALID; |
|
851 |
Value minrw = std::numeric_limits<Value>::max(); |
|
852 |
for (InArcIt a(_graph, node); a != INVALID; ++a) { |
|
853 |
Node v = _graph.source(a); |
|
854 |
Value rw = (*_node_potential)[node] + (*_node_potential)[v] - |
|
855 |
dualScale * _weight[a]; |
|
856 |
|
|
857 |
if (node == v) { |
|
858 |
if (_allow_loops && _graph.direction(a)) { |
|
859 |
_delta3->erase(a); |
|
860 |
} |
|
861 |
} else if ((*_status)[v] == EVEN) { |
|
862 |
_delta3->erase(a); |
|
863 |
if (minrw > rw) { |
|
864 |
min = _graph.oppositeArc(a); |
|
865 |
minrw = rw; |
|
866 |
} |
|
867 |
} else if ((*_status)[v] == MATCHED) { |
|
868 |
if ((*_pred)[v] == a) { |
|
869 |
Arc mina = INVALID; |
|
870 |
Value minrwa = std::numeric_limits<Value>::max(); |
|
871 |
for (OutArcIt aa(_graph, v); aa != INVALID; ++aa) { |
|
872 |
Node va = _graph.target(aa); |
|
873 |
if ((*_status)[va] != EVEN || |
|
874 |
_tree_set->find(va) == tree) continue; |
|
875 |
Value rwa = (*_node_potential)[v] + (*_node_potential)[va] - |
|
876 |
dualScale * _weight[aa]; |
|
877 |
if (minrwa > rwa) { |
|
878 |
minrwa = rwa; |
|
879 |
mina = aa; |
|
880 |
} |
|
881 |
} |
|
882 |
if (mina != INVALID) { |
|
883 |
_pred->set(v, mina); |
|
884 |
_delta2->increase(v, minrwa); |
|
885 |
} else { |
|
886 |
_pred->set(v, INVALID); |
|
887 |
_delta2->erase(v); |
|
888 |
} |
|
889 |
} |
|
890 |
} |
|
891 |
} |
|
892 |
if (min != INVALID) { |
|
893 |
_pred->set(node, min); |
|
894 |
_delta2->push(node, minrw); |
|
895 |
} else { |
|
896 |
_pred->set(node, INVALID); |
|
897 |
} |
|
898 |
} |
|
899 |
|
|
900 |
void oddToMatched(Node node) { |
|
901 |
_node_potential->set(node, (*_node_potential)[node] + _delta_sum); |
|
902 |
Arc min = INVALID; |
|
903 |
Value minrw = std::numeric_limits<Value>::max(); |
|
904 |
for (InArcIt a(_graph, node); a != INVALID; ++a) { |
|
905 |
Node v = _graph.source(a); |
|
906 |
if ((*_status)[v] != EVEN) continue; |
|
907 |
Value rw = (*_node_potential)[node] + (*_node_potential)[v] - |
|
908 |
dualScale * _weight[a]; |
|
909 |
|
|
910 |
if (minrw > rw) { |
|
911 |
min = _graph.oppositeArc(a); |
|
912 |
minrw = rw; |
|
913 |
} |
|
914 |
} |
|
915 |
if (min != INVALID) { |
|
916 |
_pred->set(node, min); |
|
917 |
_delta2->push(node, minrw); |
|
918 |
} else { |
|
919 |
_pred->set(node, INVALID); |
|
920 |
} |
|
921 |
} |
|
922 |
|
|
923 |
void alternatePath(Node even, int tree) { |
|
924 |
Node odd; |
|
925 |
|
|
926 |
_status->set(even, MATCHED); |
|
927 |
evenToMatched(even, tree); |
|
928 |
|
|
929 |
Arc prev = (*_matching)[even]; |
|
930 |
while (prev != INVALID) { |
|
931 |
odd = _graph.target(prev); |
|
932 |
even = _graph.target((*_pred)[odd]); |
|
933 |
_matching->set(odd, (*_pred)[odd]); |
|
934 |
_status->set(odd, MATCHED); |
|
935 |
oddToMatched(odd); |
|
936 |
|
|
937 |
prev = (*_matching)[even]; |
|
938 |
_status->set(even, MATCHED); |
|
939 |
_matching->set(even, _graph.oppositeArc((*_matching)[odd])); |
|
940 |
evenToMatched(even, tree); |
|
941 |
} |
|
942 |
} |
|
943 |
|
|
944 |
void destroyTree(int tree) { |
|
945 |
for (typename TreeSet::ItemIt n(*_tree_set, tree); n != INVALID; ++n) { |
|
946 |
if ((*_status)[n] == EVEN) { |
|
947 |
_status->set(n, MATCHED); |
|
948 |
evenToMatched(n, tree); |
|
949 |
} else if ((*_status)[n] == ODD) { |
|
950 |
_status->set(n, MATCHED); |
|
951 |
oddToMatched(n); |
|
952 |
} |
|
953 |
} |
|
954 |
_tree_set->eraseClass(tree); |
|
955 |
} |
|
956 |
|
|
957 |
|
|
958 |
void unmatchNode(const Node& node) { |
|
959 |
int tree = _tree_set->find(node); |
|
960 |
|
|
961 |
alternatePath(node, tree); |
|
962 |
destroyTree(tree); |
|
963 |
|
|
964 |
_matching->set(node, INVALID); |
|
965 |
} |
|
966 |
|
|
967 |
|
|
968 |
void augmentOnEdge(const Edge& edge) { |
|
969 |
Node left = _graph.u(edge); |
|
970 |
int left_tree = _tree_set->find(left); |
|
971 |
|
|
972 |
alternatePath(left, left_tree); |
|
973 |
destroyTree(left_tree); |
|
974 |
_matching->set(left, _graph.direct(edge, true)); |
|
975 |
|
|
976 |
Node right = _graph.v(edge); |
|
977 |
int right_tree = _tree_set->find(right); |
|
978 |
|
|
979 |
alternatePath(right, right_tree); |
|
980 |
destroyTree(right_tree); |
|
981 |
_matching->set(right, _graph.direct(edge, false)); |
|
982 |
} |
|
983 |
|
|
984 |
void augmentOnArc(const Arc& arc) { |
|
985 |
Node left = _graph.source(arc); |
|
986 |
_status->set(left, MATCHED); |
|
987 |
_matching->set(left, arc); |
|
988 |
_pred->set(left, arc); |
|
989 |
|
|
990 |
Node right = _graph.target(arc); |
|
991 |
int right_tree = _tree_set->find(right); |
|
992 |
|
|
993 |
alternatePath(right, right_tree); |
|
994 |
destroyTree(right_tree); |
|
995 |
_matching->set(right, _graph.oppositeArc(arc)); |
|
996 |
} |
|
997 |
|
|
998 |
void extendOnArc(const Arc& arc) { |
|
999 |
Node base = _graph.target(arc); |
|
1000 |
int tree = _tree_set->find(base); |
|
1001 |
|
|
1002 |
Node odd = _graph.source(arc); |
|
1003 |
_tree_set->insert(odd, tree); |
|
1004 |
_status->set(odd, ODD); |
|
1005 |
matchedToOdd(odd, tree); |
|
1006 |
_pred->set(odd, arc); |
|
1007 |
|
|
1008 |
Node even = _graph.target((*_matching)[odd]); |
|
1009 |
_tree_set->insert(even, tree); |
|
1010 |
_status->set(even, EVEN); |
|
1011 |
matchedToEven(even, tree); |
|
1012 |
} |
|
1013 |
|
|
1014 |
void cycleOnEdge(const Edge& edge, int tree) { |
|
1015 |
Node nca = INVALID; |
|
1016 |
std::vector<Node> left_path, right_path; |
|
1017 |
|
|
1018 |
{ |
|
1019 |
std::set<Node> left_set, right_set; |
|
1020 |
Node left = _graph.u(edge); |
|
1021 |
left_path.push_back(left); |
|
1022 |
left_set.insert(left); |
|
1023 |
|
|
1024 |
Node right = _graph.v(edge); |
|
1025 |
right_path.push_back(right); |
|
1026 |
right_set.insert(right); |
|
1027 |
|
|
1028 |
while (true) { |
|
1029 |
|
|
1030 |
if (left_set.find(right) != left_set.end()) { |
|
1031 |
nca = right; |
|
1032 |
break; |
|
1033 |
} |
|
1034 |
|
|
1035 |
if ((*_matching)[left] == INVALID) break; |
|
1036 |
|
|
1037 |
left = _graph.target((*_matching)[left]); |
|
1038 |
left_path.push_back(left); |
|
1039 |
left = _graph.target((*_pred)[left]); |
|
1040 |
left_path.push_back(left); |
|
1041 |
|
|
1042 |
left_set.insert(left); |
|
1043 |
|
|
1044 |
if (right_set.find(left) != right_set.end()) { |
|
1045 |
nca = left; |
|
1046 |
break; |
|
1047 |
} |
|
1048 |
|
|
1049 |
if ((*_matching)[right] == INVALID) break; |
|
1050 |
|
|
1051 |
right = _graph.target((*_matching)[right]); |
|
1052 |
right_path.push_back(right); |
|
1053 |
right = _graph.target((*_pred)[right]); |
|
1054 |
right_path.push_back(right); |
|
1055 |
|
|
1056 |
right_set.insert(right); |
|
1057 |
|
|
1058 |
} |
|
1059 |
|
|
1060 |
if (nca == INVALID) { |
|
1061 |
if ((*_matching)[left] == INVALID) { |
|
1062 |
nca = right; |
|
1063 |
while (left_set.find(nca) == left_set.end()) { |
|
1064 |
nca = _graph.target((*_matching)[nca]); |
|
1065 |
right_path.push_back(nca); |
|
1066 |
nca = _graph.target((*_pred)[nca]); |
|
1067 |
right_path.push_back(nca); |
|
1068 |
} |
|
1069 |
} else { |
|
1070 |
nca = left; |
|
1071 |
while (right_set.find(nca) == right_set.end()) { |
|
1072 |
nca = _graph.target((*_matching)[nca]); |
|
1073 |
left_path.push_back(nca); |
|
1074 |
nca = _graph.target((*_pred)[nca]); |
|
1075 |
left_path.push_back(nca); |
|
1076 |
} |
|
1077 |
} |
|
1078 |
} |
|
1079 |
} |
|
1080 |
|
|
1081 |
alternatePath(nca, tree); |
|
1082 |
Arc prev; |
|
1083 |
|
|
1084 |
prev = _graph.direct(edge, true); |
|
1085 |
for (int i = 0; left_path[i] != nca; i += 2) { |
|
1086 |
_matching->set(left_path[i], prev); |
|
1087 |
_status->set(left_path[i], MATCHED); |
|
1088 |
evenToMatched(left_path[i], tree); |
|
1089 |
|
|
1090 |
prev = _graph.oppositeArc((*_pred)[left_path[i + 1]]); |
|
1091 |
_status->set(left_path[i + 1], MATCHED); |
|
1092 |
oddToMatched(left_path[i + 1]); |
|
1093 |
} |
|
1094 |
_matching->set(nca, prev); |
|
1095 |
|
|
1096 |
for (int i = 0; right_path[i] != nca; i += 2) { |
|
1097 |
_status->set(right_path[i], MATCHED); |
|
1098 |
evenToMatched(right_path[i], tree); |
|
1099 |
|
|
1100 |
_matching->set(right_path[i + 1], (*_pred)[right_path[i + 1]]); |
|
1101 |
_status->set(right_path[i + 1], MATCHED); |
|
1102 |
oddToMatched(right_path[i + 1]); |
|
1103 |
} |
|
1104 |
|
|
1105 |
destroyTree(tree); |
|
1106 |
} |
|
1107 |
|
|
1108 |
void extractCycle(const Arc &arc) { |
|
1109 |
Node left = _graph.source(arc); |
|
1110 |
Node odd = _graph.target((*_matching)[left]); |
|
1111 |
Arc prev; |
|
1112 |
while (odd != left) { |
|
1113 |
Node even = _graph.target((*_matching)[odd]); |
|
1114 |
prev = (*_matching)[odd]; |
|
1115 |
odd = _graph.target((*_matching)[even]); |
|
1116 |
_matching->set(even, _graph.oppositeArc(prev)); |
|
1117 |
} |
|
1118 |
_matching->set(left, arc); |
|
1119 |
|
|
1120 |
Node right = _graph.target(arc); |
|
1121 |
int right_tree = _tree_set->find(right); |
|
1122 |
alternatePath(right, right_tree); |
|
1123 |
destroyTree(right_tree); |
|
1124 |
_matching->set(right, _graph.oppositeArc(arc)); |
|
1125 |
} |
|
1126 |
|
|
1127 |
public: |
|
1128 |
|
|
1129 |
/// \brief Constructor |
|
1130 |
/// |
|
1131 |
/// Constructor. |
|
1132 |
MaxWeightedFractionalMatching(const Graph& graph, const WeightMap& weight, |
|
1133 |
bool allow_loops = true) |
|
1134 |
: _graph(graph), _weight(weight), _matching(0), |
|
1135 |
_node_potential(0), _node_num(0), _allow_loops(allow_loops), |
|
1136 |
_status(0), _pred(0), |
|
1137 |
_tree_set_index(0), _tree_set(0), |
|
1138 |
|
|
1139 |
_delta1_index(0), _delta1(0), |
|
1140 |
_delta2_index(0), _delta2(0), |
|
1141 |
_delta3_index(0), _delta3(0), |
|
1142 |
|
|
1143 |
_delta_sum() {} |
|
1144 |
|
|
1145 |
~MaxWeightedFractionalMatching() { |
|
1146 |
destroyStructures(); |
|
1147 |
} |
|
1148 |
|
|
1149 |
/// \name Execution Control |
|
1150 |
/// The simplest way to execute the algorithm is to use the |
|
1151 |
/// \ref run() member function. |
|
1152 |
|
|
1153 |
///@{ |
|
1154 |
|
|
1155 |
/// \brief Initialize the algorithm |
|
1156 |
/// |
|
1157 |
/// This function initializes the algorithm. |
|
1158 |
void init() { |
|
1159 |
createStructures(); |
|
1160 |
|
|
1161 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
1162 |
(*_delta1_index)[n] = _delta1->PRE_HEAP; |
|
1163 |
(*_delta2_index)[n] = _delta2->PRE_HEAP; |
|
1164 |
} |
|
1165 |
for (EdgeIt e(_graph); e != INVALID; ++e) { |
|
1166 |
(*_delta3_index)[e] = _delta3->PRE_HEAP; |
|
1167 |
} |
|
1168 |
|
|
1169 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
1170 |
Value max = 0; |
|
1171 |
for (OutArcIt e(_graph, n); e != INVALID; ++e) { |
|
1172 |
if (_graph.target(e) == n && !_allow_loops) continue; |
|
1173 |
if ((dualScale * _weight[e]) / 2 > max) { |
|
1174 |
max = (dualScale * _weight[e]) / 2; |
|
1175 |
} |
|
1176 |
} |
|
1177 |
_node_potential->set(n, max); |
|
1178 |
_delta1->push(n, max); |
|
1179 |
|
|
1180 |
_tree_set->insert(n); |
|
1181 |
|
|
1182 |
_matching->set(n, INVALID); |
|
1183 |
_status->set(n, EVEN); |
|
1184 |
} |
|
1185 |
|
|
1186 |
for (EdgeIt e(_graph); e != INVALID; ++e) { |
|
1187 |
Node left = _graph.u(e); |
|
1188 |
Node right = _graph.v(e); |
|
1189 |
if (left == right && !_allow_loops) continue; |
|
1190 |
_delta3->push(e, ((*_node_potential)[left] + |
|
1191 |
(*_node_potential)[right] - |
|
1192 |
dualScale * _weight[e]) / 2); |
|
1193 |
} |
|
1194 |
} |
|
1195 |
|
|
1196 |
/// \brief Start the algorithm |
|
1197 |
/// |
|
1198 |
/// This function starts the algorithm. |
|
1199 |
/// |
|
1200 |
/// \pre \ref init() must be called before using this function. |
|
1201 |
void start() { |
|
1202 |
enum OpType { |
|
1203 |
D1, D2, D3 |
|
1204 |
}; |
|
1205 |
|
|
1206 |
int unmatched = _node_num; |
|
1207 |
while (unmatched > 0) { |
|
1208 |
Value d1 = !_delta1->empty() ? |
|
1209 |
_delta1->prio() : std::numeric_limits<Value>::max(); |
|
1210 |
|
|
1211 |
Value d2 = !_delta2->empty() ? |
|
1212 |
_delta2->prio() : std::numeric_limits<Value>::max(); |
|
1213 |
|
|
1214 |
Value d3 = !_delta3->empty() ? |
|
1215 |
_delta3->prio() : std::numeric_limits<Value>::max(); |
|
1216 |
|
|
1217 |
_delta_sum = d3; OpType ot = D3; |
|
1218 |
if (d1 < _delta_sum) { _delta_sum = d1; ot = D1; } |
|
1219 |
if (d2 < _delta_sum) { _delta_sum = d2; ot = D2; } |
|
1220 |
|
|
1221 |
switch (ot) { |
|
1222 |
case D1: |
|
1223 |
{ |
|
1224 |
Node n = _delta1->top(); |
|
1225 |
unmatchNode(n); |
|
1226 |
--unmatched; |
|
1227 |
} |
|
1228 |
break; |
|
1229 |
case D2: |
|
1230 |
{ |
|
1231 |
Node n = _delta2->top(); |
|
1232 |
Arc a = (*_pred)[n]; |
|
1233 |
if ((*_matching)[n] == INVALID) { |
|
1234 |
augmentOnArc(a); |
|
1235 |
--unmatched; |
|
1236 |
} else { |
|
1237 |
Node v = _graph.target((*_matching)[n]); |
|
1238 |
if ((*_matching)[n] != |
|
1239 |
_graph.oppositeArc((*_matching)[v])) { |
|
1240 |
extractCycle(a); |
|
1241 |
--unmatched; |
|
1242 |
} else { |
|
1243 |
extendOnArc(a); |
|
1244 |
} |
|
1245 |
} |
|
1246 |
} break; |
|
1247 |
case D3: |
|
1248 |
{ |
|
1249 |
Edge e = _delta3->top(); |
|
1250 |
|
|
1251 |
Node left = _graph.u(e); |
|
1252 |
Node right = _graph.v(e); |
|
1253 |
|
|
1254 |
int left_tree = _tree_set->find(left); |
|
1255 |
int right_tree = _tree_set->find(right); |
|
1256 |
|
|
1257 |
if (left_tree == right_tree) { |
|
1258 |
cycleOnEdge(e, left_tree); |
|
1259 |
--unmatched; |
|
1260 |
} else { |
|
1261 |
augmentOnEdge(e); |
|
1262 |
unmatched -= 2; |
|
1263 |
} |
|
1264 |
} break; |
|
1265 |
} |
|
1266 |
} |
|
1267 |
} |
|
1268 |
|
|
1269 |
/// \brief Run the algorithm. |
|
1270 |
/// |
|
1271 |
/// This method runs the \c %MaxWeightedFractionalMatching algorithm. |
|
1272 |
/// |
|
1273 |
/// \note mwfm.run() is just a shortcut of the following code. |
|
1274 |
/// \code |
|
1275 |
/// mwfm.init(); |
|
1276 |
/// mwfm.start(); |
|
1277 |
/// \endcode |
|
1278 |
void run() { |
|
1279 |
init(); |
|
1280 |
start(); |
|
1281 |
} |
|
1282 |
|
|
1283 |
/// @} |
|
1284 |
|
|
1285 |
/// \name Primal Solution |
|
1286 |
/// Functions to get the primal solution, i.e. the maximum weighted |
|
1287 |
/// matching.\n |
|
1288 |
/// Either \ref run() or \ref start() function should be called before |
|
1289 |
/// using them. |
|
1290 |
|
|
1291 |
/// @{ |
|
1292 |
|
|
1293 |
/// \brief Return the weight of the matching. |
|
1294 |
/// |
|
1295 |
/// This function returns the weight of the found matching. This |
|
1296 |
/// value is scaled by \ref primalScale "primal scale". |
|
1297 |
/// |
|
1298 |
/// \pre Either run() or start() must be called before using this function. |
|
1299 |
Value matchingWeight() const { |
|
1300 |
Value sum = 0; |
|
1301 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
1302 |
if ((*_matching)[n] != INVALID) { |
|
1303 |
sum += _weight[(*_matching)[n]]; |
|
1304 |
} |
|
1305 |
} |
|
1306 |
return sum * primalScale / 2; |
|
1307 |
} |
|
1308 |
|
|
1309 |
/// \brief Return the number of covered nodes in the matching. |
|
1310 |
/// |
|
1311 |
/// This function returns the number of covered nodes in the matching. |
|
1312 |
/// |
|
1313 |
/// \pre Either run() or start() must be called before using this function. |
|
1314 |
int matchingSize() const { |
|
1315 |
int num = 0; |
|
1316 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
1317 |
if ((*_matching)[n] != INVALID) { |
|
1318 |
++num; |
|
1319 |
} |
|
1320 |
} |
|
1321 |
return num; |
|
1322 |
} |
|
1323 |
|
|
1324 |
/// \brief Return \c true if the given edge is in the matching. |
|
1325 |
/// |
|
1326 |
/// This function returns \c true if the given edge is in the |
|
1327 |
/// found matching. The result is scaled by \ref primalScale |
|
1328 |
/// "primal scale". |
|
1329 |
/// |
|
1330 |
/// \pre Either run() or start() must be called before using this function. |
|
1331 |
int matching(const Edge& edge) const { |
|
1332 |
return (edge == (*_matching)[_graph.u(edge)] ? 1 : 0) |
|
1333 |
+ (edge == (*_matching)[_graph.v(edge)] ? 1 : 0); |
|
1334 |
} |
|
1335 |
|
|
1336 |
/// \brief Return the fractional matching arc (or edge) incident |
|
1337 |
/// to the given node. |
|
1338 |
/// |
|
1339 |
/// This function returns one of the fractional matching arc (or |
|
1340 |
/// edge) incident to the given node in the found matching or \c |
|
1341 |
/// INVALID if the node is not covered by the matching or if the |
|
1342 |
/// node is on an odd length cycle then it is the successor edge |
|
1343 |
/// on the cycle. |
|
1344 |
/// |
|
1345 |
/// \pre Either run() or start() must be called before using this function. |
|
1346 |
Arc matching(const Node& node) const { |
|
1347 |
return (*_matching)[node]; |
|
1348 |
} |
|
1349 |
|
|
1350 |
/// \brief Return a const reference to the matching map. |
|
1351 |
/// |
|
1352 |
/// This function returns a const reference to a node map that stores |
|
1353 |
/// the matching arc (or edge) incident to each node. |
|
1354 |
const MatchingMap& matchingMap() const { |
|
1355 |
return *_matching; |
|
1356 |
} |
|
1357 |
|
|
1358 |
/// @} |
|
1359 |
|
|
1360 |
/// \name Dual Solution |
|
1361 |
/// Functions to get the dual solution.\n |
|
1362 |
/// Either \ref run() or \ref start() function should be called before |
|
1363 |
/// using them. |
|
1364 |
|
|
1365 |
/// @{ |
|
1366 |
|
|
1367 |
/// \brief Return the value of the dual solution. |
|
1368 |
/// |
|
1369 |
/// This function returns the value of the dual solution. |
|
1370 |
/// It should be equal to the primal value scaled by \ref dualScale |
|
1371 |
/// "dual scale". |
|
1372 |
/// |
|
1373 |
/// \pre Either run() or start() must be called before using this function. |
|
1374 |
Value dualValue() const { |
|
1375 |
Value sum = 0; |
|
1376 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
1377 |
sum += nodeValue(n); |
|
1378 |
} |
|
1379 |
return sum; |
|
1380 |
} |
|
1381 |
|
|
1382 |
/// \brief Return the dual value (potential) of the given node. |
|
1383 |
/// |
|
1384 |
/// This function returns the dual value (potential) of the given node. |
|
1385 |
/// |
|
1386 |
/// \pre Either run() or start() must be called before using this function. |
|
1387 |
Value nodeValue(const Node& n) const { |
|
1388 |
return (*_node_potential)[n]; |
|
1389 |
} |
|
1390 |
|
|
1391 |
/// @} |
|
1392 |
|
|
1393 |
}; |
|
1394 |
|
|
1395 |
/// \ingroup matching |
|
1396 |
/// |
|
1397 |
/// \brief Weighted fractional perfect matching in general graphs |
|
1398 |
/// |
|
1399 |
/// This class provides an efficient implementation of fractional |
|
1400 |
/// matching algorithm. The implementation uses priority queues and |
|
1401 |
/// provides \f$O(nm\log n)\f$ time complexity. |
|
1402 |
/// |
|
1403 |
/// The maximum weighted fractional perfect matching is a relaxation |
|
1404 |
/// of the maximum weighted perfect matching problem where the odd |
|
1405 |
/// set constraints are omitted. |
|
1406 |
/// It can be formulated with the following linear program. |
|
1407 |
/// \f[ \sum_{e \in \delta(u)}x_e = 1 \quad \forall u\in V\f] |
|
1408 |
/// \f[x_e \ge 0\quad \forall e\in E\f] |
|
1409 |
/// \f[\max \sum_{e\in E}x_ew_e\f] |
|
1410 |
/// where \f$\delta(X)\f$ is the set of edges incident to a node in |
|
1411 |
/// \f$X\f$. The result must be the union of a matching with one |
|
1412 |
/// value edges and a set of odd length cycles with half value edges. |
|
1413 |
/// |
|
1414 |
/// The algorithm calculates an optimal fractional matching and a |
|
1415 |
/// proof of the optimality. The solution of the dual problem can be |
|
1416 |
/// used to check the result of the algorithm. The dual linear |
|
1417 |
/// problem is the following. |
|
1418 |
/// \f[ y_u + y_v \ge w_{uv} \quad \forall uv\in E\f] |
|
1419 |
/// \f[\min \sum_{u \in V}y_u \f] |
|
1420 |
/// |
|
1421 |
/// The algorithm can be executed with the run() function. |
|
1422 |
/// After it the matching (the primal solution) and the dual solution |
|
1423 |
/// can be obtained using the query functions. |
|
1424 |
/// |
|
1425 |
/// The primal solution is multiplied by |
|
1426 |
/// \ref MaxWeightedPerfectFractionalMatching::primalScale "2". |
|
1427 |
/// If the value type is integer, then the dual |
|
1428 |
/// solution is scaled by |
|
1429 |
/// \ref MaxWeightedPerfectFractionalMatching::dualScale "4". |
|
1430 |
/// |
|
1431 |
/// \tparam GR The undirected graph type the algorithm runs on. |
|
1432 |
/// \tparam WM The type edge weight map. The default type is |
|
1433 |
/// \ref concepts::Graph::EdgeMap "GR::EdgeMap<int>". |
|
1434 |
#ifdef DOXYGEN |
|
1435 |
template <typename GR, typename WM> |
|
1436 |
#else |
|
1437 |
template <typename GR, |
|
1438 |
typename WM = typename GR::template EdgeMap<int> > |
|
1439 |
#endif |
|
1440 |
class MaxWeightedPerfectFractionalMatching { |
|
1441 |
public: |
|
1442 |
|
|
1443 |
/// The graph type of the algorithm |
|
1444 |
typedef GR Graph; |
|
1445 |
/// The type of the edge weight map |
|
1446 |
typedef WM WeightMap; |
|
1447 |
/// The value type of the edge weights |
|
1448 |
typedef typename WeightMap::Value Value; |
|
1449 |
|
|
1450 |
/// The type of the matching map |
|
1451 |
typedef typename Graph::template NodeMap<typename Graph::Arc> |
|
1452 |
MatchingMap; |
|
1453 |
|
|
1454 |
/// \brief Scaling factor for primal solution |
|
1455 |
/// |
|
1456 |
/// Scaling factor for primal solution. |
|
1457 |
static const int primalScale = 2; |
|
1458 |
|
|
1459 |
/// \brief Scaling factor for dual solution |
|
1460 |
/// |
|
1461 |
/// Scaling factor for dual solution. It is equal to 4 or 1 |
|
1462 |
/// according to the value type. |
|
1463 |
static const int dualScale = |
|
1464 |
std::numeric_limits<Value>::is_integer ? 4 : 1; |
|
1465 |
|
|
1466 |
private: |
|
1467 |
|
|
1468 |
TEMPLATE_GRAPH_TYPEDEFS(Graph); |
|
1469 |
|
|
1470 |
typedef typename Graph::template NodeMap<Value> NodePotential; |
|
1471 |
|
|
1472 |
const Graph& _graph; |
|
1473 |
const WeightMap& _weight; |
|
1474 |
|
|
1475 |
MatchingMap* _matching; |
|
1476 |
NodePotential* _node_potential; |
|
1477 |
|
|
1478 |
int _node_num; |
|
1479 |
bool _allow_loops; |
|
1480 |
|
|
1481 |
enum Status { |
|
1482 |
EVEN = -1, MATCHED = 0, ODD = 1 |
|
1483 |
}; |
|
1484 |
|
|
1485 |
typedef typename Graph::template NodeMap<Status> StatusMap; |
|
1486 |
StatusMap* _status; |
|
1487 |
|
|
1488 |
typedef typename Graph::template NodeMap<Arc> PredMap; |
|
1489 |
PredMap* _pred; |
|
1490 |
|
|
1491 |
typedef ExtendFindEnum<IntNodeMap> TreeSet; |
|
1492 |
|
|
1493 |
IntNodeMap *_tree_set_index; |
|
1494 |
TreeSet *_tree_set; |
|
1495 |
|
|
1496 |
IntNodeMap *_delta2_index; |
|
1497 |
BinHeap<Value, IntNodeMap> *_delta2; |
|
1498 |
|
|
1499 |
IntEdgeMap *_delta3_index; |
|
1500 |
BinHeap<Value, IntEdgeMap> *_delta3; |
|
1501 |
|
|
1502 |
Value _delta_sum; |
|
1503 |
|
|
1504 |
void createStructures() { |
|
1505 |
_node_num = countNodes(_graph); |
|
1506 |
|
|
1507 |
if (!_matching) { |
|
1508 |
_matching = new MatchingMap(_graph); |
|
1509 |
} |
|
1510 |
if (!_node_potential) { |
|
1511 |
_node_potential = new NodePotential(_graph); |
|
1512 |
} |
|
1513 |
if (!_status) { |
|
1514 |
_status = new StatusMap(_graph); |
|
1515 |
} |
|
1516 |
if (!_pred) { |
|
1517 |
_pred = new PredMap(_graph); |
|
1518 |
} |
|
1519 |
if (!_tree_set) { |
|
1520 |
_tree_set_index = new IntNodeMap(_graph); |
|
1521 |
_tree_set = new TreeSet(*_tree_set_index); |
|
1522 |
} |
|
1523 |
if (!_delta2) { |
|
1524 |
_delta2_index = new IntNodeMap(_graph); |
|
1525 |
_delta2 = new BinHeap<Value, IntNodeMap>(*_delta2_index); |
|
1526 |
} |
|
1527 |
if (!_delta3) { |
|
1528 |
_delta3_index = new IntEdgeMap(_graph); |
|
1529 |
_delta3 = new BinHeap<Value, IntEdgeMap>(*_delta3_index); |
|
1530 |
} |
|
1531 |
} |
|
1532 |
|
|
1533 |
void destroyStructures() { |
|
1534 |
if (_matching) { |
|
1535 |
delete _matching; |
|
1536 |
} |
|
1537 |
if (_node_potential) { |
|
1538 |
delete _node_potential; |
|
1539 |
} |
|
1540 |
if (_status) { |
|
1541 |
delete _status; |
|
1542 |
} |
|
1543 |
if (_pred) { |
|
1544 |
delete _pred; |
|
1545 |
} |
|
1546 |
if (_tree_set) { |
|
1547 |
delete _tree_set_index; |
|
1548 |
delete _tree_set; |
|
1549 |
} |
|
1550 |
if (_delta2) { |
|
1551 |
delete _delta2_index; |
|
1552 |
delete _delta2; |
|
1553 |
} |
|
1554 |
if (_delta3) { |
|
1555 |
delete _delta3_index; |
|
1556 |
delete _delta3; |
|
1557 |
} |
|
1558 |
} |
|
1559 |
|
|
1560 |
void matchedToEven(Node node, int tree) { |
|
1561 |
_tree_set->insert(node, tree); |
|
1562 |
_node_potential->set(node, (*_node_potential)[node] + _delta_sum); |
|
1563 |
|
|
1564 |
if (_delta2->state(node) == _delta2->IN_HEAP) { |
|
1565 |
_delta2->erase(node); |
|
1566 |
} |
|
1567 |
|
|
1568 |
for (InArcIt a(_graph, node); a != INVALID; ++a) { |
|
1569 |
Node v = _graph.source(a); |
|
1570 |
Value rw = (*_node_potential)[node] + (*_node_potential)[v] - |
|
1571 |
dualScale * _weight[a]; |
|
1572 |
if (node == v) { |
|
1573 |
if (_allow_loops && _graph.direction(a)) { |
|
1574 |
_delta3->push(a, rw / 2); |
|
1575 |
} |
|
1576 |
} else if ((*_status)[v] == EVEN) { |
|
1577 |
_delta3->push(a, rw / 2); |
|
1578 |
} else if ((*_status)[v] == MATCHED) { |
|
1579 |
if (_delta2->state(v) != _delta2->IN_HEAP) { |
|
1580 |
_pred->set(v, a); |
|
1581 |
_delta2->push(v, rw); |
|
1582 |
} else if ((*_delta2)[v] > rw) { |
|
1583 |
_pred->set(v, a); |
|
1584 |
_delta2->decrease(v, rw); |
|
1585 |
} |
|
1586 |
} |
|
1587 |
} |
|
1588 |
} |
|
1589 |
|
|
1590 |
void matchedToOdd(Node node, int tree) { |
|
1591 |
_tree_set->insert(node, tree); |
|
1592 |
_node_potential->set(node, (*_node_potential)[node] - _delta_sum); |
|
1593 |
|
|
1594 |
if (_delta2->state(node) == _delta2->IN_HEAP) { |
|
1595 |
_delta2->erase(node); |
|
1596 |
} |
|
1597 |
} |
|
1598 |
|
|
1599 |
void evenToMatched(Node node, int tree) { |
|
1600 |
_node_potential->set(node, (*_node_potential)[node] - _delta_sum); |
|
1601 |
Arc min = INVALID; |
|
1602 |
Value minrw = std::numeric_limits<Value>::max(); |
|
1603 |
for (InArcIt a(_graph, node); a != INVALID; ++a) { |
|
1604 |
Node v = _graph.source(a); |
|
1605 |
Value rw = (*_node_potential)[node] + (*_node_potential)[v] - |
|
1606 |
dualScale * _weight[a]; |
|
1607 |
|
|
1608 |
if (node == v) { |
|
1609 |
if (_allow_loops && _graph.direction(a)) { |
|
1610 |
_delta3->erase(a); |
|
1611 |
} |
|
1612 |
} else if ((*_status)[v] == EVEN) { |
|
1613 |
_delta3->erase(a); |
|
1614 |
if (minrw > rw) { |
|
1615 |
min = _graph.oppositeArc(a); |
|
1616 |
minrw = rw; |
|
1617 |
} |
|
1618 |
} else if ((*_status)[v] == MATCHED) { |
|
1619 |
if ((*_pred)[v] == a) { |
|
1620 |
Arc mina = INVALID; |
|
1621 |
Value minrwa = std::numeric_limits<Value>::max(); |
|
1622 |
for (OutArcIt aa(_graph, v); aa != INVALID; ++aa) { |
|
1623 |
Node va = _graph.target(aa); |
|
1624 |
if ((*_status)[va] != EVEN || |
|
1625 |
_tree_set->find(va) == tree) continue; |
|
1626 |
Value rwa = (*_node_potential)[v] + (*_node_potential)[va] - |
|
1627 |
dualScale * _weight[aa]; |
|
1628 |
if (minrwa > rwa) { |
|
1629 |
minrwa = rwa; |
|
1630 |
mina = aa; |
|
1631 |
} |
|
1632 |
} |
|
1633 |
if (mina != INVALID) { |
|
1634 |
_pred->set(v, mina); |
|
1635 |
_delta2->increase(v, minrwa); |
|
1636 |
} else { |
|
1637 |
_pred->set(v, INVALID); |
|
1638 |
_delta2->erase(v); |
|
1639 |
} |
|
1640 |
} |
|
1641 |
} |
|
1642 |
} |
|
1643 |
if (min != INVALID) { |
|
1644 |
_pred->set(node, min); |
|
1645 |
_delta2->push(node, minrw); |
|
1646 |
} else { |
|
1647 |
_pred->set(node, INVALID); |
|
1648 |
} |
|
1649 |
} |
|
1650 |
|
|
1651 |
void oddToMatched(Node node) { |
|
1652 |
_node_potential->set(node, (*_node_potential)[node] + _delta_sum); |
|
1653 |
Arc min = INVALID; |
|
1654 |
Value minrw = std::numeric_limits<Value>::max(); |
|
1655 |
for (InArcIt a(_graph, node); a != INVALID; ++a) { |
|
1656 |
Node v = _graph.source(a); |
|
1657 |
if ((*_status)[v] != EVEN) continue; |
|
1658 |
Value rw = (*_node_potential)[node] + (*_node_potential)[v] - |
|
1659 |
dualScale * _weight[a]; |
|
1660 |
|
|
1661 |
if (minrw > rw) { |
|
1662 |
min = _graph.oppositeArc(a); |
|
1663 |
minrw = rw; |
|
1664 |
} |
|
1665 |
} |
|
1666 |
if (min != INVALID) { |
|
1667 |
_pred->set(node, min); |
|
1668 |
_delta2->push(node, minrw); |
|
1669 |
} else { |
|
1670 |
_pred->set(node, INVALID); |
|
1671 |
} |
|
1672 |
} |
|
1673 |
|
|
1674 |
void alternatePath(Node even, int tree) { |
|
1675 |
Node odd; |
|
1676 |
|
|
1677 |
_status->set(even, MATCHED); |
|
1678 |
evenToMatched(even, tree); |
|
1679 |
|
|
1680 |
Arc prev = (*_matching)[even]; |
|
1681 |
while (prev != INVALID) { |
|
1682 |
odd = _graph.target(prev); |
|
1683 |
even = _graph.target((*_pred)[odd]); |
|
1684 |
_matching->set(odd, (*_pred)[odd]); |
|
1685 |
_status->set(odd, MATCHED); |
|
1686 |
oddToMatched(odd); |
|
1687 |
|
|
1688 |
prev = (*_matching)[even]; |
|
1689 |
_status->set(even, MATCHED); |
|
1690 |
_matching->set(even, _graph.oppositeArc((*_matching)[odd])); |
|
1691 |
evenToMatched(even, tree); |
|
1692 |
} |
|
1693 |
} |
|
1694 |
|
|
1695 |
void destroyTree(int tree) { |
|
1696 |
for (typename TreeSet::ItemIt n(*_tree_set, tree); n != INVALID; ++n) { |
|
1697 |
if ((*_status)[n] == EVEN) { |
|
1698 |
_status->set(n, MATCHED); |
|
1699 |
evenToMatched(n, tree); |
|
1700 |
} else if ((*_status)[n] == ODD) { |
|
1701 |
_status->set(n, MATCHED); |
|
1702 |
oddToMatched(n); |
|
1703 |
} |
|
1704 |
} |
|
1705 |
_tree_set->eraseClass(tree); |
|
1706 |
} |
|
1707 |
|
|
1708 |
void augmentOnEdge(const Edge& edge) { |
|
1709 |
Node left = _graph.u(edge); |
|
1710 |
int left_tree = _tree_set->find(left); |
|
1711 |
|
|
1712 |
alternatePath(left, left_tree); |
|
1713 |
destroyTree(left_tree); |
|
1714 |
_matching->set(left, _graph.direct(edge, true)); |
|
1715 |
|
|
1716 |
Node right = _graph.v(edge); |
|
1717 |
int right_tree = _tree_set->find(right); |
|
1718 |
|
|
1719 |
alternatePath(right, right_tree); |
|
1720 |
destroyTree(right_tree); |
|
1721 |
_matching->set(right, _graph.direct(edge, false)); |
|
1722 |
} |
|
1723 |
|
|
1724 |
void augmentOnArc(const Arc& arc) { |
|
1725 |
Node left = _graph.source(arc); |
|
1726 |
_status->set(left, MATCHED); |
|
1727 |
_matching->set(left, arc); |
|
1728 |
_pred->set(left, arc); |
|
1729 |
|
|
1730 |
Node right = _graph.target(arc); |
|
1731 |
int right_tree = _tree_set->find(right); |
|
1732 |
|
|
1733 |
alternatePath(right, right_tree); |
|
1734 |
destroyTree(right_tree); |
|
1735 |
_matching->set(right, _graph.oppositeArc(arc)); |
|
1736 |
} |
|
1737 |
|
|
1738 |
void extendOnArc(const Arc& arc) { |
|
1739 |
Node base = _graph.target(arc); |
|
1740 |
int tree = _tree_set->find(base); |
|
1741 |
|
|
1742 |
Node odd = _graph.source(arc); |
|
1743 |
_tree_set->insert(odd, tree); |
|
1744 |
_status->set(odd, ODD); |
|
1745 |
matchedToOdd(odd, tree); |
|
1746 |
_pred->set(odd, arc); |
|
1747 |
|
|
1748 |
Node even = _graph.target((*_matching)[odd]); |
|
1749 |
_tree_set->insert(even, tree); |
|
1750 |
_status->set(even, EVEN); |
|
1751 |
matchedToEven(even, tree); |
|
1752 |
} |
|
1753 |
|
|
1754 |
void cycleOnEdge(const Edge& edge, int tree) { |
|
1755 |
Node nca = INVALID; |
|
1756 |
std::vector<Node> left_path, right_path; |
|
1757 |
|
|
1758 |
{ |
|
1759 |
std::set<Node> left_set, right_set; |
|
1760 |
Node left = _graph.u(edge); |
|
1761 |
left_path.push_back(left); |
|
1762 |
left_set.insert(left); |
|
1763 |
|
|
1764 |
Node right = _graph.v(edge); |
|
1765 |
right_path.push_back(right); |
|
1766 |
right_set.insert(right); |
|
1767 |
|
|
1768 |
while (true) { |
|
1769 |
|
|
1770 |
if (left_set.find(right) != left_set.end()) { |
|
1771 |
nca = right; |
|
1772 |
break; |
|
1773 |
} |
|
1774 |
|
|
1775 |
if ((*_matching)[left] == INVALID) break; |
|
1776 |
|
|
1777 |
left = _graph.target((*_matching)[left]); |
|
1778 |
left_path.push_back(left); |
|
1779 |
left = _graph.target((*_pred)[left]); |
|
1780 |
left_path.push_back(left); |
|
1781 |
|
|
1782 |
left_set.insert(left); |
|
1783 |
|
|
1784 |
if (right_set.find(left) != right_set.end()) { |
|
1785 |
nca = left; |
|
1786 |
break; |
|
1787 |
} |
|
1788 |
|
|
1789 |
if ((*_matching)[right] == INVALID) break; |
|
1790 |
|
|
1791 |
right = _graph.target((*_matching)[right]); |
|
1792 |
right_path.push_back(right); |
|
1793 |
right = _graph.target((*_pred)[right]); |
|
1794 |
right_path.push_back(right); |
|
1795 |
|
|
1796 |
right_set.insert(right); |
|
1797 |
|
|
1798 |
} |
|
1799 |
|
|
1800 |
if (nca == INVALID) { |
|
1801 |
if ((*_matching)[left] == INVALID) { |
|
1802 |
nca = right; |
|
1803 |
while (left_set.find(nca) == left_set.end()) { |
|
1804 |
nca = _graph.target((*_matching)[nca]); |
|
1805 |
right_path.push_back(nca); |
|
1806 |
nca = _graph.target((*_pred)[nca]); |
|
1807 |
right_path.push_back(nca); |
|
1808 |
} |
|
1809 |
} else { |
|
1810 |
nca = left; |
|
1811 |
while (right_set.find(nca) == right_set.end()) { |
|
1812 |
nca = _graph.target((*_matching)[nca]); |
|
1813 |
left_path.push_back(nca); |
|
1814 |
nca = _graph.target((*_pred)[nca]); |
|
1815 |
left_path.push_back(nca); |
|
1816 |
} |
|
1817 |
} |
|
1818 |
} |
|
1819 |
} |
|
1820 |
|
|
1821 |
alternatePath(nca, tree); |
|
1822 |
Arc prev; |
|
1823 |
|
|
1824 |
prev = _graph.direct(edge, true); |
|
1825 |
for (int i = 0; left_path[i] != nca; i += 2) { |
|
1826 |
_matching->set(left_path[i], prev); |
|
1827 |
_status->set(left_path[i], MATCHED); |
|
1828 |
evenToMatched(left_path[i], tree); |
|
1829 |
|
|
1830 |
prev = _graph.oppositeArc((*_pred)[left_path[i + 1]]); |
|
1831 |
_status->set(left_path[i + 1], MATCHED); |
|
1832 |
oddToMatched(left_path[i + 1]); |
|
1833 |
} |
|
1834 |
_matching->set(nca, prev); |
|
1835 |
|
|
1836 |
for (int i = 0; right_path[i] != nca; i += 2) { |
|
1837 |
_status->set(right_path[i], MATCHED); |
|
1838 |
evenToMatched(right_path[i], tree); |
|
1839 |
|
|
1840 |
_matching->set(right_path[i + 1], (*_pred)[right_path[i + 1]]); |
|
1841 |
_status->set(right_path[i + 1], MATCHED); |
|
1842 |
oddToMatched(right_path[i + 1]); |
|
1843 |
} |
|
1844 |
|
|
1845 |
destroyTree(tree); |
|
1846 |
} |
|
1847 |
|
|
1848 |
void extractCycle(const Arc &arc) { |
|
1849 |
Node left = _graph.source(arc); |
|
1850 |
Node odd = _graph.target((*_matching)[left]); |
|
1851 |
Arc prev; |
|
1852 |
while (odd != left) { |
|
1853 |
Node even = _graph.target((*_matching)[odd]); |
|
1854 |
prev = (*_matching)[odd]; |
|
1855 |
odd = _graph.target((*_matching)[even]); |
|
1856 |
_matching->set(even, _graph.oppositeArc(prev)); |
|
1857 |
} |
|
1858 |
_matching->set(left, arc); |
|
1859 |
|
|
1860 |
Node right = _graph.target(arc); |
|
1861 |
int right_tree = _tree_set->find(right); |
|
1862 |
alternatePath(right, right_tree); |
|
1863 |
destroyTree(right_tree); |
|
1864 |
_matching->set(right, _graph.oppositeArc(arc)); |
|
1865 |
} |
|
1866 |
|
|
1867 |
public: |
|
1868 |
|
|
1869 |
/// \brief Constructor |
|
1870 |
/// |
|
1871 |
/// Constructor. |
|
1872 |
MaxWeightedPerfectFractionalMatching(const Graph& graph, |
|
1873 |
const WeightMap& weight, |
|
1874 |
bool allow_loops = true) |
|
1875 |
: _graph(graph), _weight(weight), _matching(0), |
|
1876 |
_node_potential(0), _node_num(0), _allow_loops(allow_loops), |
|
1877 |
_status(0), _pred(0), |
|
1878 |
_tree_set_index(0), _tree_set(0), |
|
1879 |
|
|
1880 |
_delta2_index(0), _delta2(0), |
|
1881 |
_delta3_index(0), _delta3(0), |
|
1882 |
|
|
1883 |
_delta_sum() {} |
|
1884 |
|
|
1885 |
~MaxWeightedPerfectFractionalMatching() { |
|
1886 |
destroyStructures(); |
|
1887 |
} |
|
1888 |
|
|
1889 |
/// \name Execution Control |
|
1890 |
/// The simplest way to execute the algorithm is to use the |
|
1891 |
/// \ref run() member function. |
|
1892 |
|
|
1893 |
///@{ |
|
1894 |
|
|
1895 |
/// \brief Initialize the algorithm |
|
1896 |
/// |
|
1897 |
/// This function initializes the algorithm. |
|
1898 |
void init() { |
|
1899 |
createStructures(); |
|
1900 |
|
|
1901 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
1902 |
(*_delta2_index)[n] = _delta2->PRE_HEAP; |
|
1903 |
} |
|
1904 |
for (EdgeIt e(_graph); e != INVALID; ++e) { |
|
1905 |
(*_delta3_index)[e] = _delta3->PRE_HEAP; |
|
1906 |
} |
|
1907 |
|
|
1908 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
1909 |
Value max = - std::numeric_limits<Value>::max(); |
|
1910 |
for (OutArcIt e(_graph, n); e != INVALID; ++e) { |
|
1911 |
if (_graph.target(e) == n && !_allow_loops) continue; |
|
1912 |
if ((dualScale * _weight[e]) / 2 > max) { |
|
1913 |
max = (dualScale * _weight[e]) / 2; |
|
1914 |
} |
|
1915 |
} |
|
1916 |
_node_potential->set(n, max); |
|
1917 |
|
|
1918 |
_tree_set->insert(n); |
|
1919 |
|
|
1920 |
_matching->set(n, INVALID); |
|
1921 |
_status->set(n, EVEN); |
|
1922 |
} |
|
1923 |
|
|
1924 |
for (EdgeIt e(_graph); e != INVALID; ++e) { |
|
1925 |
Node left = _graph.u(e); |
|
1926 |
Node right = _graph.v(e); |
|
1927 |
if (left == right && !_allow_loops) continue; |
|
1928 |
_delta3->push(e, ((*_node_potential)[left] + |
|
1929 |
(*_node_potential)[right] - |
|
1930 |
dualScale * _weight[e]) / 2); |
|
1931 |
} |
|
1932 |
} |
|
1933 |
|
|
1934 |
/// \brief Start the algorithm |
|
1935 |
/// |
|
1936 |
/// This function starts the algorithm. |
|
1937 |
/// |
|
1938 |
/// \pre \ref init() must be called before using this function. |
|
1939 |
bool start() { |
|
1940 |
enum OpType { |
|
1941 |
D2, D3 |
|
1942 |
}; |
|
1943 |
|
|
1944 |
int unmatched = _node_num; |
|
1945 |
while (unmatched > 0) { |
|
1946 |
Value d2 = !_delta2->empty() ? |
|
1947 |
_delta2->prio() : std::numeric_limits<Value>::max(); |
|
1948 |
|
|
1949 |
Value d3 = !_delta3->empty() ? |
|
1950 |
_delta3->prio() : std::numeric_limits<Value>::max(); |
|
1951 |
|
|
1952 |
_delta_sum = d3; OpType ot = D3; |
|
1953 |
if (d2 < _delta_sum) { _delta_sum = d2; ot = D2; } |
|
1954 |
|
|
1955 |
if (_delta_sum == std::numeric_limits<Value>::max()) { |
|
1956 |
return false; |
|
1957 |
} |
|
1958 |
|
|
1959 |
switch (ot) { |
|
1960 |
case D2: |
|
1961 |
{ |
|
1962 |
Node n = _delta2->top(); |
|
1963 |
Arc a = (*_pred)[n]; |
|
1964 |
if ((*_matching)[n] == INVALID) { |
|
1965 |
augmentOnArc(a); |
|
1966 |
--unmatched; |
|
1967 |
} else { |
|
1968 |
Node v = _graph.target((*_matching)[n]); |
|
1969 |
if ((*_matching)[n] != |
|
1970 |
_graph.oppositeArc((*_matching)[v])) { |
|
1971 |
extractCycle(a); |
|
1972 |
--unmatched; |
|
1973 |
} else { |
|
1974 |
extendOnArc(a); |
|
1975 |
} |
|
1976 |
} |
|
1977 |
} break; |
|
1978 |
case D3: |
|
1979 |
{ |
|
1980 |
Edge e = _delta3->top(); |
|
1981 |
|
|
1982 |
Node left = _graph.u(e); |
|
1983 |
Node right = _graph.v(e); |
|
1984 |
|
|
1985 |
int left_tree = _tree_set->find(left); |
|
1986 |
int right_tree = _tree_set->find(right); |
|
1987 |
|
|
1988 |
if (left_tree == right_tree) { |
|
1989 |
cycleOnEdge(e, left_tree); |
|
1990 |
--unmatched; |
|
1991 |
} else { |
|
1992 |
augmentOnEdge(e); |
|
1993 |
unmatched -= 2; |
|
1994 |
} |
|
1995 |
} break; |
|
1996 |
} |
|
1997 |
} |
|
1998 |
return true; |
|
1999 |
} |
|
2000 |
|
|
2001 |
/// \brief Run the algorithm. |
|
2002 |
/// |
|
2003 |
/// This method runs the \c %MaxWeightedPerfectFractionalMatching |
|
2004 |
/// algorithm. |
|
2005 |
/// |
|
2006 |
/// \note mwfm.run() is just a shortcut of the following code. |
|
2007 |
/// \code |
|
2008 |
/// mwpfm.init(); |
|
2009 |
/// mwpfm.start(); |
|
2010 |
/// \endcode |
|
2011 |
bool run() { |
|
2012 |
init(); |
|
2013 |
return start(); |
|
2014 |
} |
|
2015 |
|
|
2016 |
/// @} |
|
2017 |
|
|
2018 |
/// \name Primal Solution |
|
2019 |
/// Functions to get the primal solution, i.e. the maximum weighted |
|
2020 |
/// matching.\n |
|
2021 |
/// Either \ref run() or \ref start() function should be called before |
|
2022 |
/// using them. |
|
2023 |
|
|
2024 |
/// @{ |
|
2025 |
|
|
2026 |
/// \brief Return the weight of the matching. |
|
2027 |
/// |
|
2028 |
/// This function returns the weight of the found matching. This |
|
2029 |
/// value is scaled by \ref primalScale "primal scale". |
|
2030 |
/// |
|
2031 |
/// \pre Either run() or start() must be called before using this function. |
|
2032 |
Value matchingWeight() const { |
|
2033 |
Value sum = 0; |
|
2034 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
2035 |
if ((*_matching)[n] != INVALID) { |
|
2036 |
sum += _weight[(*_matching)[n]]; |
|
2037 |
} |
|
2038 |
} |
|
2039 |
return sum * primalScale / 2; |
|
2040 |
} |
|
2041 |
|
|
2042 |
/// \brief Return the number of covered nodes in the matching. |
|
2043 |
/// |
|
2044 |
/// This function returns the number of covered nodes in the matching. |
|
2045 |
/// |
|
2046 |
/// \pre Either run() or start() must be called before using this function. |
|
2047 |
int matchingSize() const { |
|
2048 |
int num = 0; |
|
2049 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
2050 |
if ((*_matching)[n] != INVALID) { |
|
2051 |
++num; |
|
2052 |
} |
|
2053 |
} |
|
2054 |
return num; |
|
2055 |
} |
|
2056 |
|
|
2057 |
/// \brief Return \c true if the given edge is in the matching. |
|
2058 |
/// |
|
2059 |
/// This function returns \c true if the given edge is in the |
|
2060 |
/// found matching. The result is scaled by \ref primalScale |
|
2061 |
/// "primal scale". |
|
2062 |
/// |
|
2063 |
/// \pre Either run() or start() must be called before using this function. |
|
2064 |
int matching(const Edge& edge) const { |
|
2065 |
return (edge == (*_matching)[_graph.u(edge)] ? 1 : 0) |
|
2066 |
+ (edge == (*_matching)[_graph.v(edge)] ? 1 : 0); |
|
2067 |
} |
|
2068 |
|
|
2069 |
/// \brief Return the fractional matching arc (or edge) incident |
|
2070 |
/// to the given node. |
|
2071 |
/// |
|
2072 |
/// This function returns one of the fractional matching arc (or |
|
2073 |
/// edge) incident to the given node in the found matching or \c |
|
2074 |
/// INVALID if the node is not covered by the matching or if the |
|
2075 |
/// node is on an odd length cycle then it is the successor edge |
|
2076 |
/// on the cycle. |
|
2077 |
/// |
|
2078 |
/// \pre Either run() or start() must be called before using this function. |
|
2079 |
Arc matching(const Node& node) const { |
|
2080 |
return (*_matching)[node]; |
|
2081 |
} |
|
2082 |
|
|
2083 |
/// \brief Return a const reference to the matching map. |
|
2084 |
/// |
|
2085 |
/// This function returns a const reference to a node map that stores |
|
2086 |
/// the matching arc (or edge) incident to each node. |
|
2087 |
const MatchingMap& matchingMap() const { |
|
2088 |
return *_matching; |
|
2089 |
} |
|
2090 |
|
|
2091 |
/// @} |
|
2092 |
|
|
2093 |
/// \name Dual Solution |
|
2094 |
/// Functions to get the dual solution.\n |
|
2095 |
/// Either \ref run() or \ref start() function should be called before |
|
2096 |
/// using them. |
|
2097 |
|
|
2098 |
/// @{ |
|
2099 |
|
|
2100 |
/// \brief Return the value of the dual solution. |
|
2101 |
/// |
|
2102 |
/// This function returns the value of the dual solution. |
|
2103 |
/// It should be equal to the primal value scaled by \ref dualScale |
|
2104 |
/// "dual scale". |
|
2105 |
/// |
|
2106 |
/// \pre Either run() or start() must be called before using this function. |
|
2107 |
Value dualValue() const { |
|
2108 |
Value sum = 0; |
|
2109 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
2110 |
sum += nodeValue(n); |
|
2111 |
} |
|
2112 |
return sum; |
|
2113 |
} |
|
2114 |
|
|
2115 |
/// \brief Return the dual value (potential) of the given node. |
|
2116 |
/// |
|
2117 |
/// This function returns the dual value (potential) of the given node. |
|
2118 |
/// |
|
2119 |
/// \pre Either run() or start() must be called before using this function. |
|
2120 |
Value nodeValue(const Node& n) const { |
|
2121 |
return (*_node_potential)[n]; |
|
2122 |
} |
|
2123 |
|
|
2124 |
/// @} |
|
2125 |
|
|
2126 |
}; |
|
2127 |
|
|
2128 |
} //END OF NAMESPACE LEMON |
|
2129 |
|
|
2130 |
#endif //LEMON_FRACTIONAL_MATCHING_H |
1 |
/* -*- mode: C++; indent-tabs-mode: nil; -*- |
|
2 |
* |
|
3 |
* This file is a part of LEMON, a generic C++ optimization library. |
|
4 |
* |
|
5 |
* Copyright (C) 2003-2009 |
|
6 |
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
|
7 |
* (Egervary Research Group on Combinatorial Optimization, EGRES). |
|
8 |
* |
|
9 |
* Permission to use, modify and distribute this software is granted |
|
10 |
* provided that this copyright notice appears in all copies. For |
|
11 |
* precise terms see the accompanying LICENSE file. |
|
12 |
* |
|
13 |
* This software is provided "AS IS" with no warranty of any kind, |
|
14 |
* express or implied, and with no claim as to its suitability for any |
|
15 |
* purpose. |
|
16 |
* |
|
17 |
*/ |
|
18 |
|
|
19 |
#include <iostream> |
|
20 |
#include <sstream> |
|
21 |
#include <vector> |
|
22 |
#include <queue> |
|
23 |
#include <cstdlib> |
|
24 |
|
|
25 |
#include <lemon/fractional_matching.h> |
|
26 |
#include <lemon/smart_graph.h> |
|
27 |
#include <lemon/concepts/graph.h> |
|
28 |
#include <lemon/concepts/maps.h> |
|
29 |
#include <lemon/lgf_reader.h> |
|
30 |
#include <lemon/math.h> |
|
31 |
|
|
32 |
#include "test_tools.h" |
|
33 |
|
|
34 |
using namespace std; |
|
35 |
using namespace lemon; |
|
36 |
|
|
37 |
GRAPH_TYPEDEFS(SmartGraph); |
|
38 |
|
|
39 |
|
|
40 |
const int lgfn = 4; |
|
41 |
const std::string lgf[lgfn] = { |
|
42 |
"@nodes\n" |
|
43 |
"label\n" |
|
44 |
"0\n" |
|
45 |
"1\n" |
|
46 |
"2\n" |
|
47 |
"3\n" |
|
48 |
"4\n" |
|
49 |
"5\n" |
|
50 |
"6\n" |
|
51 |
"7\n" |
|
52 |
"@edges\n" |
|
53 |
" label weight\n" |
|
54 |
"7 4 0 984\n" |
|
55 |
"0 7 1 73\n" |
|
56 |
"7 1 2 204\n" |
|
57 |
"2 3 3 583\n" |
|
58 |
"2 7 4 565\n" |
|
59 |
"2 1 5 582\n" |
|
60 |
"0 4 6 551\n" |
|
61 |
"2 5 7 385\n" |
|
62 |
"1 5 8 561\n" |
|
63 |
"5 3 9 484\n" |
|
64 |
"7 5 10 904\n" |
|
65 |
"3 6 11 47\n" |
|
66 |
"7 6 12 888\n" |
|
67 |
"3 0 13 747\n" |
|
68 |
"6 1 14 310\n", |
|
69 |
|
|
70 |
"@nodes\n" |
|
71 |
"label\n" |
|
72 |
"0\n" |
|
73 |
"1\n" |
|
74 |
"2\n" |
|
75 |
"3\n" |
|
76 |
"4\n" |
|
77 |
"5\n" |
|
78 |
"6\n" |
|
79 |
"7\n" |
|
80 |
"@edges\n" |
|
81 |
" label weight\n" |
|
82 |
"2 5 0 710\n" |
|
83 |
"0 5 1 241\n" |
|
84 |
"2 4 2 856\n" |
|
85 |
"2 6 3 762\n" |
|
86 |
"4 1 4 747\n" |
|
87 |
"6 1 5 962\n" |
|
88 |
"4 7 6 723\n" |
|
89 |
"1 7 7 661\n" |
|
90 |
"2 3 8 376\n" |
|
91 |
"1 0 9 416\n" |
|
92 |
"6 7 10 391\n", |
|
93 |
|
|
94 |
"@nodes\n" |
|
95 |
"label\n" |
|
96 |
"0\n" |
|
97 |
"1\n" |
|
98 |
"2\n" |
|
99 |
"3\n" |
|
100 |
"4\n" |
|
101 |
"5\n" |
|
102 |
"6\n" |
|
103 |
"7\n" |
|
104 |
"@edges\n" |
|
105 |
" label weight\n" |
|
106 |
"6 2 0 553\n" |
|
107 |
"0 7 1 653\n" |
|
108 |
"6 3 2 22\n" |
|
109 |
"4 7 3 846\n" |
|
110 |
"7 2 4 981\n" |
|
111 |
"7 6 5 250\n" |
|
112 |
"5 2 6 539\n", |
|
113 |
|
|
114 |
"@nodes\n" |
|
115 |
"label\n" |
|
116 |
"0\n" |
|
117 |
"@edges\n" |
|
118 |
" label weight\n" |
|
119 |
"0 0 0 100\n" |
|
120 |
}; |
|
121 |
|
|
122 |
void checkMaxFractionalMatchingCompile() |
|
123 |
{ |
|
124 |
typedef concepts::Graph Graph; |
|
125 |
typedef Graph::Node Node; |
|
126 |
typedef Graph::Edge Edge; |
|
127 |
|
|
128 |
Graph g; |
|
129 |
Node n; |
|
130 |
Edge e; |
|
131 |
|
|
132 |
MaxFractionalMatching<Graph> mat_test(g); |
|
133 |
const MaxFractionalMatching<Graph>& |
|
134 |
const_mat_test = mat_test; |
|
135 |
|
|
136 |
mat_test.init(); |
|
137 |
mat_test.start(); |
|
138 |
mat_test.start(true); |
|
139 |
mat_test.startPerfect(); |
|
140 |
mat_test.startPerfect(true); |
|
141 |
mat_test.run(); |
|
142 |
mat_test.run(true); |
|
143 |
mat_test.runPerfect(); |
|
144 |
mat_test.runPerfect(true); |
|
145 |
|
|
146 |
const_mat_test.matchingSize(); |
|
147 |
const_mat_test.matching(e); |
|
148 |
const_mat_test.matching(n); |
|
149 |
const MaxFractionalMatching<Graph>::MatchingMap& mmap = |
|
150 |
const_mat_test.matchingMap(); |
|
151 |
e = mmap[n]; |
|
152 |
|
|
153 |
const_mat_test.barrier(n); |
|
154 |
} |
|
155 |
|
|
156 |
void checkMaxWeightedFractionalMatchingCompile() |
|
157 |
{ |
|
158 |
typedef concepts::Graph Graph; |
|
159 |
typedef Graph::Node Node; |
|
160 |
typedef Graph::Edge Edge; |
|
161 |
typedef Graph::EdgeMap<int> WeightMap; |
|
162 |
|
|
163 |
Graph g; |
|
164 |
Node n; |
|
165 |
Edge e; |
|
166 |
WeightMap w(g); |
|
167 |
|
|
168 |
MaxWeightedFractionalMatching<Graph> mat_test(g, w); |
|
169 |
const MaxWeightedFractionalMatching<Graph>& |
|
170 |
const_mat_test = mat_test; |
|
171 |
|
|
172 |
mat_test.init(); |
|
173 |
mat_test.start(); |
|
174 |
mat_test.run(); |
|
175 |
|
|
176 |
const_mat_test.matchingWeight(); |
|
177 |
const_mat_test.matchingSize(); |
|
178 |
const_mat_test.matching(e); |
|
179 |
const_mat_test.matching(n); |
|
180 |
const MaxWeightedFractionalMatching<Graph>::MatchingMap& mmap = |
|
181 |
const_mat_test.matchingMap(); |
|
182 |
e = mmap[n]; |
|
183 |
|
|
184 |
const_mat_test.dualValue(); |
|
185 |
const_mat_test.nodeValue(n); |
|
186 |
} |
|
187 |
|
|
188 |
void checkMaxWeightedPerfectFractionalMatchingCompile() |
|
189 |
{ |
|
190 |
typedef concepts::Graph Graph; |
|
191 |
typedef Graph::Node Node; |
|
192 |
typedef Graph::Edge Edge; |
|
193 |
typedef Graph::EdgeMap<int> WeightMap; |
|
194 |
|
|
195 |
Graph g; |
|
196 |
Node n; |
|
197 |
Edge e; |
|
198 |
WeightMap w(g); |
|
199 |
|
|
200 |
MaxWeightedPerfectFractionalMatching<Graph> mat_test(g, w); |
|
201 |
const MaxWeightedPerfectFractionalMatching<Graph>& |
|
202 |
const_mat_test = mat_test; |
|
203 |
|
|
204 |
mat_test.init(); |
|
205 |
mat_test.start(); |
|
206 |
mat_test.run(); |
|
207 |
|
|
208 |
const_mat_test.matchingWeight(); |
|
209 |
const_mat_test.matching(e); |
|
210 |
const_mat_test.matching(n); |
|
211 |
const MaxWeightedPerfectFractionalMatching<Graph>::MatchingMap& mmap = |
|
212 |
const_mat_test.matchingMap(); |
|
213 |
e = mmap[n]; |
|
214 |
|
|
215 |
const_mat_test.dualValue(); |
|
216 |
const_mat_test.nodeValue(n); |
|
217 |
} |
|
218 |
|
|
219 |
void checkFractionalMatching(const SmartGraph& graph, |
|
220 |
const MaxFractionalMatching<SmartGraph>& mfm, |
|
221 |
bool allow_loops = true) { |
|
222 |
int pv = 0; |
|
223 |
for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) { |
|
224 |
int indeg = 0; |
|
225 |
for (InArcIt a(graph, n); a != INVALID; ++a) { |
|
226 |
if (mfm.matching(graph.source(a)) == a) { |
|
227 |
++indeg; |
|
228 |
} |
|
229 |
} |
|
230 |
if (mfm.matching(n) != INVALID) { |
|
231 |
check(indeg == 1, "Invalid matching"); |
|
232 |
++pv; |
|
233 |
} else { |
|
234 |
check(indeg == 0, "Invalid matching"); |
|
235 |
} |
|
236 |
} |
|
237 |
check(pv == mfm.matchingSize(), "Wrong matching size"); |
|
238 |
|
|
239 |
for (SmartGraph::EdgeIt e(graph); e != INVALID; ++e) { |
|
240 |
check((e == mfm.matching(graph.u(e)) ? 1 : 0) + |
|
241 |
(e == mfm.matching(graph.v(e)) ? 1 : 0) == |
|
242 |
mfm.matching(e), "Invalid matching"); |
|
243 |
} |
|
244 |
|
|
245 |
SmartGraph::NodeMap<bool> processed(graph, false); |
|
246 |
for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) { |
|
247 |
if (processed[n]) continue; |
|
248 |
processed[n] = true; |
|
249 |
if (mfm.matching(n) == INVALID) continue; |
|
250 |
int num = 1; |
|
251 |
Node v = graph.target(mfm.matching(n)); |
|
252 |
while (v != n) { |
|
253 |
processed[v] = true; |
|
254 |
++num; |
|
255 |
v = graph.target(mfm.matching(v)); |
|
256 |
} |
|
257 |
check(num == 2 || num % 2 == 1, "Wrong cycle size"); |
|
258 |
check(allow_loops || num != 1, "Wrong cycle size"); |
|
259 |
} |
|
260 |
|
|
261 |
int anum = 0, bnum = 0; |
|
262 |
SmartGraph::NodeMap<bool> neighbours(graph, false); |
|
263 |
for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) { |
|
264 |
if (!mfm.barrier(n)) continue; |
|
265 |
++anum; |
|
266 |
for (SmartGraph::InArcIt a(graph, n); a != INVALID; ++a) { |
|
267 |
Node u = graph.source(a); |
|
268 |
if (!allow_loops && u == n) continue; |
|
269 |
if (!neighbours[u]) { |
|
270 |
neighbours[u] = true; |
|
271 |
++bnum; |
|
272 |
} |
|
273 |
} |
|
274 |
} |
|
275 |
check(anum - bnum + mfm.matchingSize() == countNodes(graph), |
|
276 |
"Wrong barrier"); |
|
277 |
} |
|
278 |
|
|
279 |
void checkPerfectFractionalMatching(const SmartGraph& graph, |
|
280 |
const MaxFractionalMatching<SmartGraph>& mfm, |
|
281 |
bool perfect, bool allow_loops = true) { |
|
282 |
if (perfect) { |
|
283 |
for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) { |
|
284 |
int indeg = 0; |
|
285 |
for (InArcIt a(graph, n); a != INVALID; ++a) { |
|
286 |
if (mfm.matching(graph.source(a)) == a) { |
|
287 |
++indeg; |
|
288 |
} |
|
289 |
} |
|
290 |
check(mfm.matching(n) != INVALID, "Invalid matching"); |
|
291 |
check(indeg == 1, "Invalid matching"); |
|
292 |
} |
|
293 |
for (SmartGraph::EdgeIt e(graph); e != INVALID; ++e) { |
|
294 |
check((e == mfm.matching(graph.u(e)) ? 1 : 0) + |
|
295 |
(e == mfm.matching(graph.v(e)) ? 1 : 0) == |
|
296 |
mfm.matching(e), "Invalid matching"); |
|
297 |
} |
|
298 |
} else { |
|
299 |
int anum = 0, bnum = 0; |
|
300 |
SmartGraph::NodeMap<bool> neighbours(graph, false); |
|
301 |
for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) { |
|
302 |
if (!mfm.barrier(n)) continue; |
|
303 |
++anum; |
|
304 |
for (SmartGraph::InArcIt a(graph, n); a != INVALID; ++a) { |
|
305 |
Node u = graph.source(a); |
|
306 |
if (!allow_loops && u == n) continue; |
|
307 |
if (!neighbours[u]) { |
|
308 |
neighbours[u] = true; |
|
309 |
++bnum; |
|
310 |
} |
|
311 |
} |
|
312 |
} |
|
313 |
check(anum - bnum > 0, "Wrong barrier"); |
|
314 |
} |
|
315 |
} |
|
316 |
|
|
317 |
void checkWeightedFractionalMatching(const SmartGraph& graph, |
|
318 |
const SmartGraph::EdgeMap<int>& weight, |
|
319 |
const MaxWeightedFractionalMatching<SmartGraph>& mwfm, |
|
320 |
bool allow_loops = true) { |
|
321 |
for (SmartGraph::EdgeIt e(graph); e != INVALID; ++e) { |
|
322 |
if (graph.u(e) == graph.v(e) && !allow_loops) continue; |
|
323 |
int rw = mwfm.nodeValue(graph.u(e)) + mwfm.nodeValue(graph.v(e)) |
|
324 |
- weight[e] * mwfm.dualScale; |
|
325 |
|
|
326 |
check(rw >= 0, "Negative reduced weight"); |
|
327 |
check(rw == 0 || !mwfm.matching(e), |
|
328 |
"Non-zero reduced weight on matching edge"); |
|
329 |
} |
|
330 |
|
|
331 |
int pv = 0; |
|
332 |
for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) { |
|
333 |
int indeg = 0; |
|
334 |
for (InArcIt a(graph, n); a != INVALID; ++a) { |
|
335 |
if (mwfm.matching(graph.source(a)) == a) { |
|
336 |
++indeg; |
|
337 |
} |
|
338 |
} |
|
339 |
check(indeg <= 1, "Invalid matching"); |
|
340 |
if (mwfm.matching(n) != INVALID) { |
|
341 |
check(mwfm.nodeValue(n) >= 0, "Invalid node value"); |
|
342 |
check(indeg == 1, "Invalid matching"); |
|
343 |
pv += weight[mwfm.matching(n)]; |
|
344 |
SmartGraph::Node o = graph.target(mwfm.matching(n)); |
|
345 |
} else { |
|
346 |
check(mwfm.nodeValue(n) == 0, "Invalid matching"); |
|
347 |
check(indeg == 0, "Invalid matching"); |
|
348 |
} |
|
349 |
} |
|
350 |
|
|
351 |
for (SmartGraph::EdgeIt e(graph); e != INVALID; ++e) { |
|
352 |
check((e == mwfm.matching(graph.u(e)) ? 1 : 0) + |
|
353 |
(e == mwfm.matching(graph.v(e)) ? 1 : 0) == |
|
354 |
mwfm.matching(e), "Invalid matching"); |
|
355 |
} |
|
356 |
|
|
357 |
int dv = 0; |
|
358 |
for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) { |
|
359 |
dv += mwfm.nodeValue(n); |
|
360 |
} |
|
361 |
|
|
362 |
check(pv * mwfm.dualScale == dv * 2, "Wrong duality"); |
|
363 |
|
|
364 |
SmartGraph::NodeMap<bool> processed(graph, false); |
|
365 |
for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) { |
|
366 |
if (processed[n]) continue; |
|
367 |
processed[n] = true; |
|
368 |
if (mwfm.matching(n) == INVALID) continue; |
|
369 |
int num = 1; |
|
370 |
Node v = graph.target(mwfm.matching(n)); |
|
371 |
while (v != n) { |
|
372 |
processed[v] = true; |
|
373 |
++num; |
|
374 |
v = graph.target(mwfm.matching(v)); |
|
375 |
} |
|
376 |
check(num == 2 || num % 2 == 1, "Wrong cycle size"); |
|
377 |
check(allow_loops || num != 1, "Wrong cycle size"); |
|
378 |
} |
|
379 |
|
|
380 |
return; |
|
381 |
} |
|
382 |
|
|
383 |
void checkWeightedPerfectFractionalMatching(const SmartGraph& graph, |
|
384 |
const SmartGraph::EdgeMap<int>& weight, |
|
385 |
const MaxWeightedPerfectFractionalMatching<SmartGraph>& mwpfm, |
|
386 |
bool allow_loops = true) { |
|
387 |
for (SmartGraph::EdgeIt e(graph); e != INVALID; ++e) { |
|
388 |
if (graph.u(e) == graph.v(e) && !allow_loops) continue; |
|
389 |
int rw = mwpfm.nodeValue(graph.u(e)) + mwpfm.nodeValue(graph.v(e)) |
|
390 |
- weight[e] * mwpfm.dualScale; |
|
391 |
|
|
392 |
check(rw >= 0, "Negative reduced weight"); |
|
393 |
check(rw == 0 || !mwpfm.matching(e), |
|
394 |
"Non-zero reduced weight on matching edge"); |
|
395 |
} |
|
396 |
|
|
397 |
int pv = 0; |
|
398 |
for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) { |
|
399 |
int indeg = 0; |
|
400 |
for (InArcIt a(graph, n); a != INVALID; ++a) { |
|
401 |
if (mwpfm.matching(graph.source(a)) == a) { |
|
402 |
++indeg; |
|
403 |
} |
|
404 |
} |
|
405 |
check(mwpfm.matching(n) != INVALID, "Invalid perfect matching"); |
|
406 |
check(indeg == 1, "Invalid perfect matching"); |
|
407 |
pv += weight[mwpfm.matching(n)]; |
|
408 |
SmartGraph::Node o = graph.target(mwpfm.matching(n)); |
|
409 |
} |
|
410 |
|
|
411 |
for (SmartGraph::EdgeIt e(graph); e != INVALID; ++e) { |
|
412 |
check((e == mwpfm.matching(graph.u(e)) ? 1 : 0) + |
|
413 |
(e == mwpfm.matching(graph.v(e)) ? 1 : 0) == |
|
414 |
mwpfm.matching(e), "Invalid matching"); |
|
415 |
} |
|
416 |
|
|
417 |
int dv = 0; |
|
418 |
for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) { |
|
419 |
dv += mwpfm.nodeValue(n); |
|
420 |
} |
|
421 |
|
|
422 |
check(pv * mwpfm.dualScale == dv * 2, "Wrong duality"); |
|
423 |
|
|
424 |
SmartGraph::NodeMap<bool> processed(graph, false); |
|
425 |
for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) { |
|
426 |
if (processed[n]) continue; |
|
427 |
processed[n] = true; |
|
428 |
if (mwpfm.matching(n) == INVALID) continue; |
|
429 |
int num = 1; |
|
430 |
Node v = graph.target(mwpfm.matching(n)); |
|
431 |
while (v != n) { |
|
432 |
processed[v] = true; |
|
433 |
++num; |
|
434 |
v = graph.target(mwpfm.matching(v)); |
|
435 |
} |
|
436 |
check(num == 2 || num % 2 == 1, "Wrong cycle size"); |
|
437 |
check(allow_loops || num != 1, "Wrong cycle size"); |
|
438 |
} |
|
439 |
|
|
440 |
return; |
|
441 |
} |
|
442 |
|
|
443 |
|
|
444 |
int main() { |
|
445 |
|
|
446 |
for (int i = 0; i < lgfn; ++i) { |
|
447 |
SmartGraph graph; |
|
448 |
SmartGraph::EdgeMap<int> weight(graph); |
|
449 |
|
|
450 |
istringstream lgfs(lgf[i]); |
|
451 |
graphReader(graph, lgfs). |
|
452 |
edgeMap("weight", weight).run(); |
|
453 |
|
|
454 |
bool perfect_with_loops; |
|
455 |
{ |
|
456 |
MaxFractionalMatching<SmartGraph> mfm(graph, true); |
|
457 |
mfm.run(); |
|
458 |
checkFractionalMatching(graph, mfm, true); |
|
459 |
perfect_with_loops = mfm.matchingSize() == countNodes(graph); |
|
460 |
} |
|
461 |
|
|
462 |
bool perfect_without_loops; |
|
463 |
{ |
|
464 |
MaxFractionalMatching<SmartGraph> mfm(graph, false); |
|
465 |
mfm.run(); |
|
466 |
checkFractionalMatching(graph, mfm, false); |
|
467 |
perfect_without_loops = mfm.matchingSize() == countNodes(graph); |
|
468 |
} |
|
469 |
|
|
470 |
{ |
|
471 |
MaxFractionalMatching<SmartGraph> mfm(graph, true); |
|
472 |
bool result = mfm.runPerfect(); |
|
473 |
checkPerfectFractionalMatching(graph, mfm, result, true); |
|
474 |
check(result == perfect_with_loops, "Wrong perfect matching"); |
|
475 |
} |
|
476 |
|
|
477 |
{ |
|
478 |
MaxFractionalMatching<SmartGraph> mfm(graph, false); |
|
479 |
bool result = mfm.runPerfect(); |
|
480 |
checkPerfectFractionalMatching(graph, mfm, result, false); |
|
481 |
check(result == perfect_without_loops, "Wrong perfect matching"); |
|
482 |
} |
|
483 |
|
|
484 |
{ |
|
485 |
MaxWeightedFractionalMatching<SmartGraph> mwfm(graph, weight, true); |
|
486 |
mwfm.run(); |
|
487 |
checkWeightedFractionalMatching(graph, weight, mwfm, true); |
|
488 |
} |
|
489 |
|
|
490 |
{ |
|
491 |
MaxWeightedFractionalMatching<SmartGraph> mwfm(graph, weight, false); |
|
492 |
mwfm.run(); |
|
493 |
checkWeightedFractionalMatching(graph, weight, mwfm, false); |
|
494 |
} |
|
495 |
|
|
496 |
{ |
|
497 |
MaxWeightedPerfectFractionalMatching<SmartGraph> mwpfm(graph, weight, |
|
498 |
true); |
|
499 |
bool perfect = mwpfm.run(); |
|
500 |
check(perfect == (mwpfm.matchingSize() == countNodes(graph)), |
|
501 |
"Perfect matching found"); |
|
502 |
check(perfect == perfect_with_loops, "Wrong perfect matching"); |
|
503 |
|
|
504 |
if (perfect) { |
|
505 |
checkWeightedPerfectFractionalMatching(graph, weight, mwpfm, true); |
|
506 |
} |
|
507 |
} |
|
508 |
|
|
509 |
{ |
|
510 |
MaxWeightedPerfectFractionalMatching<SmartGraph> mwpfm(graph, weight, |
|
511 |
false); |
|
512 |
bool perfect = mwpfm.run(); |
|
513 |
check(perfect == (mwpfm.matchingSize() == countNodes(graph)), |
|
514 |
"Perfect matching found"); |
|
515 |
check(perfect == perfect_without_loops, "Wrong perfect matching"); |
|
516 |
|
|
517 |
if (perfect) { |
|
518 |
checkWeightedPerfectFractionalMatching(graph, weight, mwpfm, false); |
|
519 |
} |
|
520 |
} |
|
521 |
|
|
522 |
} |
|
523 |
|
|
524 |
return 0; |
|
525 |
} |
... | ... |
@@ -383,13 +383,13 @@ |
383 | 383 |
|
384 | 384 |
In most cases the \ref Preflow algorithm provides the |
385 | 385 |
fastest method for computing a maximum flow. All implementations |
386 | 386 |
also provide functions to query the minimum cut, which is the dual |
387 | 387 |
problem of maximum flow. |
388 | 388 |
|
389 |
\ref Circulation is a preflow push-relabel algorithm implemented directly |
|
389 |
\ref Circulation is a preflow push-relabel algorithm implemented directly |
|
390 | 390 |
for finding feasible circulations, which is a somewhat different problem, |
391 | 391 |
but it is strongly related to maximum flow. |
392 | 392 |
For more information, see \ref Circulation. |
393 | 393 |
*/ |
394 | 394 |
|
395 | 395 |
/** |
... | ... |
@@ -519,12 +519,19 @@ |
519 | 519 |
maximum cardinality matching in general graphs. |
520 | 520 |
- \ref MaxWeightedMatching Edmond's blossom shrinking algorithm for calculating |
521 | 521 |
maximum weighted matching in general graphs. |
522 | 522 |
- \ref MaxWeightedPerfectMatching |
523 | 523 |
Edmond's blossom shrinking algorithm for calculating maximum weighted |
524 | 524 |
perfect matching in general graphs. |
525 |
- \ref MaxFractionalMatching Push-relabel algorithm for calculating |
|
526 |
maximum cardinality fractional matching in general graphs. |
|
527 |
- \ref MaxWeightedFractionalMatching Augmenting path algorithm for calculating |
|
528 |
maximum weighted fractional matching in general graphs. |
|
529 |
- \ref MaxWeightedPerfectFractionalMatching |
|
530 |
Augmenting path algorithm for calculating maximum weighted |
|
531 |
perfect fractional matching in general graphs. |
|
525 | 532 |
|
526 | 533 |
\image html matching.png |
527 | 534 |
\image latex matching.eps "Min Cost Perfect Matching" width=\textwidth |
528 | 535 |
*/ |
529 | 536 |
|
530 | 537 |
/** |
... | ... |
@@ -81,12 +81,13 @@ |
81 | 81 |
lemon/dimacs.h \ |
82 | 82 |
lemon/edge_set.h \ |
83 | 83 |
lemon/elevator.h \ |
84 | 84 |
lemon/error.h \ |
85 | 85 |
lemon/euler.h \ |
86 | 86 |
lemon/fib_heap.h \ |
87 |
lemon/fractional_matching.h \ |
|
87 | 88 |
lemon/full_graph.h \ |
88 | 89 |
lemon/glpk.h \ |
89 | 90 |
lemon/gomory_hu.h \ |
90 | 91 |
lemon/graph_to_eps.h \ |
91 | 92 |
lemon/grid_graph.h \ |
92 | 93 |
lemon/hartmann_orlin_mmc.h \ |
... | ... |
@@ -13,24 +13,25 @@ |
13 | 13 |
* This software is provided "AS IS" with no warranty of any kind, |
14 | 14 |
* express or implied, and with no claim as to its suitability for any |
15 | 15 |
* purpose. |
16 | 16 |
* |
17 | 17 |
*/ |
18 | 18 |
|
19 |
#ifndef LEMON_MAX_MATCHING_H |
|
20 |
#define LEMON_MAX_MATCHING_H |
|
19 |
#ifndef LEMON_MATCHING_H |
|
20 |
#define LEMON_MATCHING_H |
|
21 | 21 |
|
22 | 22 |
#include <vector> |
23 | 23 |
#include <queue> |
24 | 24 |
#include <set> |
25 | 25 |
#include <limits> |
26 | 26 |
|
27 | 27 |
#include <lemon/core.h> |
28 | 28 |
#include <lemon/unionfind.h> |
29 | 29 |
#include <lemon/bin_heap.h> |
30 | 30 |
#include <lemon/maps.h> |
31 |
#include <lemon/fractional_matching.h> |
|
31 | 32 |
|
32 | 33 |
///\ingroup matching |
33 | 34 |
///\file |
34 | 35 |
///\brief Maximum matching algorithms in general graphs. |
35 | 36 |
|
36 | 37 |
namespace lemon { |
... | ... |
@@ -38,13 +39,13 @@ |
38 | 39 |
/// \ingroup matching |
39 | 40 |
/// |
40 | 41 |
/// \brief Maximum cardinality matching in general graphs |
41 | 42 |
/// |
42 | 43 |
/// This class implements Edmonds' alternating forest matching algorithm |
43 | 44 |
/// for finding a maximum cardinality matching in a general undirected graph. |
44 |
/// It can be started from an arbitrary initial matching |
|
45 |
/// It can be started from an arbitrary initial matching |
|
45 | 46 |
/// (the default is the empty one). |
46 | 47 |
/// |
47 | 48 |
/// The dual solution of the problem is a map of the nodes to |
48 | 49 |
/// \ref MaxMatching::Status "Status", having values \c EVEN (or \c D), |
49 | 50 |
/// \c ODD (or \c A) and \c MATCHED (or \c C) defining the Gallai-Edmonds |
50 | 51 |
/// decomposition of the graph. The nodes in \c EVEN/D induce a subgraph |
... | ... |
@@ -66,17 +67,17 @@ |
66 | 67 |
/// The type of the matching map |
67 | 68 |
typedef typename Graph::template NodeMap<typename Graph::Arc> |
68 | 69 |
MatchingMap; |
69 | 70 |
|
70 | 71 |
///\brief Status constants for Gallai-Edmonds decomposition. |
71 | 72 |
/// |
72 |
///These constants are used for indicating the Gallai-Edmonds |
|
73 |
///These constants are used for indicating the Gallai-Edmonds |
|
73 | 74 |
///decomposition of a graph. The nodes with status \c EVEN (or \c D) |
74 | 75 |
///induce a subgraph with factor-critical components, the nodes with |
75 | 76 |
///status \c ODD (or \c A) form the canonical barrier, and the nodes |
76 |
///with status \c MATCHED (or \c C) induce a subgraph having a |
|
77 |
///with status \c MATCHED (or \c C) induce a subgraph having a |
|
77 | 78 |
///perfect matching. |
78 | 79 |
enum Status { |
79 | 80 |
EVEN = 1, ///< = 1. (\c D is an alias for \c EVEN.) |
80 | 81 |
D = 1, |
81 | 82 |
MATCHED = 0, ///< = 0. (\c C is an alias for \c MATCHED.) |
82 | 83 |
C = 0, |
... | ... |
@@ -509,13 +510,13 @@ |
509 | 510 |
(*_status)[n] = EVEN; |
510 | 511 |
processSparse(n); |
511 | 512 |
} |
512 | 513 |
} |
513 | 514 |
} |
514 | 515 |
|
515 |
/// \brief Start Edmonds' algorithm with a heuristic improvement |
|
516 |
/// \brief Start Edmonds' algorithm with a heuristic improvement |
|
516 | 517 |
/// for dense graphs |
517 | 518 |
/// |
518 | 519 |
/// This function runs Edmonds' algorithm with a heuristic of postponing |
519 | 520 |
/// shrinks, therefore resulting in a faster algorithm for dense graphs. |
520 | 521 |
/// |
521 | 522 |
/// \pre \ref init(), \ref greedyInit() or \ref matchingInit() must be |
... | ... |
@@ -531,14 +532,14 @@ |
531 | 532 |
} |
532 | 533 |
} |
533 | 534 |
|
534 | 535 |
|
535 | 536 |
/// \brief Run Edmonds' algorithm |
536 | 537 |
/// |
537 |
/// This function runs Edmonds' algorithm. An additional heuristic of |
|
538 |
/// postponing shrinks is used for relatively dense graphs |
|
538 |
/// This function runs Edmonds' algorithm. An additional heuristic of |
|
539 |
/// postponing shrinks is used for relatively dense graphs |
|
539 | 540 |
/// (for which <tt>m>=2*n</tt> holds). |
540 | 541 |
void run() { |
541 | 542 |
if (countEdges(_graph) < 2 * countNodes(_graph)) { |
542 | 543 |
greedyInit(); |
543 | 544 |
startSparse(); |
544 | 545 |
} else { |
... | ... |
@@ -553,13 +554,13 @@ |
553 | 554 |
/// Functions to get the primal solution, i.e. the maximum matching. |
554 | 555 |
|
555 | 556 |
/// @{ |
556 | 557 |
|
557 | 558 |
/// \brief Return the size (cardinality) of the matching. |
558 | 559 |
/// |
559 |
/// This function returns the size (cardinality) of the current matching. |
|
560 |
/// This function returns the size (cardinality) of the current matching. |
|
560 | 561 |
/// After run() it returns the size of the maximum matching in the graph. |
561 | 562 |
int matchingSize() const { |
562 | 563 |
int size = 0; |
563 | 564 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
564 | 565 |
if ((*_matching)[n] != INVALID) { |
565 | 566 |
++size; |
... | ... |
@@ -567,22 +568,22 @@ |
567 | 568 |
} |
568 | 569 |
return size / 2; |
569 | 570 |
} |
570 | 571 |
|
571 | 572 |
/// \brief Return \c true if the given edge is in the matching. |
572 | 573 |
/// |
573 |
/// This function returns \c true if the given edge is in the current |
|
574 |
/// This function returns \c true if the given edge is in the current |
|
574 | 575 |
/// matching. |
575 | 576 |
bool matching(const Edge& edge) const { |
576 | 577 |
return edge == (*_matching)[_graph.u(edge)]; |
577 | 578 |
} |
578 | 579 |
|
579 | 580 |
/// \brief Return the matching arc (or edge) incident to the given node. |
580 | 581 |
/// |
581 | 582 |
/// This function returns the matching arc (or edge) incident to the |
582 |
/// given node in the current matching or \c INVALID if the node is |
|
583 |
/// given node in the current matching or \c INVALID if the node is |
|
583 | 584 |
/// not covered by the matching. |
584 | 585 |
Arc matching(const Node& n) const { |
585 | 586 |
return (*_matching)[n]; |
586 | 587 |
} |
587 | 588 |
|
588 | 589 |
/// \brief Return a const reference to the matching map. |
... | ... |
@@ -592,23 +593,23 @@ |
592 | 593 |
const MatchingMap& matchingMap() const { |
593 | 594 |
return *_matching; |
594 | 595 |
} |
595 | 596 |
|
596 | 597 |
/// \brief Return the mate of the given node. |
597 | 598 |
/// |
598 |
/// This function returns the mate of the given node in the current |
|
599 |
/// This function returns the mate of the given node in the current |
|
599 | 600 |
/// matching or \c INVALID if the node is not covered by the matching. |
600 | 601 |
Node mate(const Node& n) const { |
601 | 602 |
return (*_matching)[n] != INVALID ? |
602 | 603 |
_graph.target((*_matching)[n]) : INVALID; |
603 | 604 |
} |
604 | 605 |
|
605 | 606 |
/// @} |
606 | 607 |
|
607 | 608 |
/// \name Dual Solution |
608 |
/// Functions to get the dual solution, i.e. the Gallai-Edmonds |
|
609 |
/// Functions to get the dual solution, i.e. the Gallai-Edmonds |
|
609 | 610 |
/// decomposition. |
610 | 611 |
|
611 | 612 |
/// @{ |
612 | 613 |
|
613 | 614 |
/// \brief Return the status of the given node in the Edmonds-Gallai |
614 | 615 |
/// decomposition. |
... | ... |
@@ -645,14 +646,14 @@ |
645 | 646 |
/// |
646 | 647 |
/// This class provides an efficient implementation of Edmond's |
647 | 648 |
/// maximum weighted matching algorithm. The implementation is based |
648 | 649 |
/// on extensive use of priority queues and provides |
649 | 650 |
/// \f$O(nm\log n)\f$ time complexity. |
650 | 651 |
/// |
651 |
/// The maximum weighted matching problem is to find a subset of the |
|
652 |
/// edges in an undirected graph with maximum overall weight for which |
|
652 |
/// The maximum weighted matching problem is to find a subset of the |
|
653 |
/// edges in an undirected graph with maximum overall weight for which |
|
653 | 654 |
/// each node has at most one incident edge. |
654 | 655 |
/// It can be formulated with the following linear program. |
655 | 656 |
/// \f[ \sum_{e \in \delta(u)}x_e \le 1 \quad \forall u\in V\f] |
656 | 657 |
/** \f[ \sum_{e \in \gamma(B)}x_e \le \frac{\vert B \vert - 1}{2} |
657 | 658 |
\quad \forall B\in\mathcal{O}\f] */ |
658 | 659 |
/// \f[x_e \ge 0\quad \forall e\in E\f] |
... | ... |
@@ -670,22 +671,22 @@ |
670 | 671 |
z_B \ge w_{uv} \quad \forall uv\in E\f] */ |
671 | 672 |
/// \f[y_u \ge 0 \quad \forall u \in V\f] |
672 | 673 |
/// \f[z_B \ge 0 \quad \forall B \in \mathcal{O}\f] |
673 | 674 |
/** \f[\min \sum_{u \in V}y_u + \sum_{B \in \mathcal{O}} |
674 | 675 |
\frac{\vert B \vert - 1}{2}z_B\f] */ |
675 | 676 |
/// |
676 |
/// The algorithm can be executed with the run() function. |
|
677 |
/// The algorithm can be executed with the run() function. |
|
677 | 678 |
/// After it the matching (the primal solution) and the dual solution |
678 |
/// can be obtained using the query functions and the |
|
679 |
/// \ref MaxWeightedMatching::BlossomIt "BlossomIt" nested class, |
|
680 |
/// |
|
679 |
/// can be obtained using the query functions and the |
|
680 |
/// \ref MaxWeightedMatching::BlossomIt "BlossomIt" nested class, |
|
681 |
/// which is able to iterate on the nodes of a blossom. |
|
681 | 682 |
/// If the value type is integer, then the dual solution is multiplied |
682 | 683 |
/// by \ref MaxWeightedMatching::dualScale "4". |
683 | 684 |
/// |
684 | 685 |
/// \tparam GR The undirected graph type the algorithm runs on. |
685 |
/// \tparam WM The type edge weight map. The default type is |
|
686 |
/// \tparam WM The type edge weight map. The default type is |
|
686 | 687 |
/// \ref concepts::Graph::EdgeMap "GR::EdgeMap<int>". |
687 | 688 |
#ifdef DOXYGEN |
688 | 689 |
template <typename GR, typename WM> |
689 | 690 |
#else |
690 | 691 |
template <typename GR, |
691 | 692 |
typename WM = typename GR::template EdgeMap<int> > |
... | ... |
@@ -742,13 +743,13 @@ |
742 | 743 |
int _node_num; |
743 | 744 |
int _blossom_num; |
744 | 745 |
|
745 | 746 |
typedef RangeMap<int> IntIntMap; |
746 | 747 |
|
747 | 748 |
enum Status { |
748 |
EVEN = -1, MATCHED = 0, ODD = 1 |
|
749 |
EVEN = -1, MATCHED = 0, ODD = 1 |
|
749 | 750 |
}; |
750 | 751 |
|
751 | 752 |
typedef HeapUnionFind<Value, IntNodeMap> BlossomSet; |
752 | 753 |
struct BlossomData { |
753 | 754 |
int tree; |
754 | 755 |
Status status; |
... | ... |
@@ -794,12 +795,16 @@ |
794 | 795 |
BinHeap<Value, IntEdgeMap> *_delta3; |
795 | 796 |
|
796 | 797 |
IntIntMap *_delta4_index; |
797 | 798 |
BinHeap<Value, IntIntMap> *_delta4; |
798 | 799 |
|
799 | 800 |
Value _delta_sum; |
801 |
int _unmatched; |
|
802 |
|
|
803 |
typedef MaxWeightedFractionalMatching<Graph, WeightMap> FractionalMatching; |
|
804 |
FractionalMatching *_fractional; |
|
800 | 805 |
|
801 | 806 |
void createStructures() { |
802 | 807 |
_node_num = countNodes(_graph); |
803 | 808 |
_blossom_num = _node_num * 3 / 2; |
804 | 809 |
|
805 | 810 |
if (!_matching) { |
... | ... |
@@ -841,15 +846,12 @@ |
841 | 846 |
_delta4_index = new IntIntMap(_blossom_num); |
842 | 847 |
_delta4 = new BinHeap<Value, IntIntMap>(*_delta4_index); |
843 | 848 |
} |
844 | 849 |
} |
845 | 850 |
|
846 | 851 |
void destroyStructures() { |
847 |
_node_num = countNodes(_graph); |
|
848 |
_blossom_num = _node_num * 3 / 2; |
|
849 |
|
|
850 | 852 |
if (_matching) { |
851 | 853 |
delete _matching; |
852 | 854 |
} |
853 | 855 |
if (_node_potential) { |
854 | 856 |
delete _node_potential; |
855 | 857 |
} |
... | ... |
@@ -919,16 +921,12 @@ |
919 | 921 |
dualScale * _weight[e]; |
920 | 922 |
|
921 | 923 |
if ((*_blossom_data)[vb].status == EVEN) { |
922 | 924 |
if (_delta3->state(e) != _delta3->IN_HEAP && blossom != vb) { |
923 | 925 |
_delta3->push(e, rw / 2); |
924 | 926 |
} |
925 |
} else if ((*_blossom_data)[vb].status == UNMATCHED) { |
|
926 |
if (_delta3->state(e) != _delta3->IN_HEAP) { |
|
927 |
_delta3->push(e, rw); |
|
928 |
} |
|
929 | 927 |
} else { |
930 | 928 |
typename std::map<int, Arc>::iterator it = |
931 | 929 |
(*_node_data)[vi].heap_index.find(tree); |
932 | 930 |
|
933 | 931 |
if (it != (*_node_data)[vi].heap_index.end()) { |
934 | 932 |
if ((*_node_data)[vi].heap[it->second] > rw) { |
... | ... |
@@ -946,313 +944,209 @@ |
946 | 944 |
|
947 | 945 |
if ((*_blossom_data)[vb].status == MATCHED) { |
948 | 946 |
if (_delta2->state(vb) != _delta2->IN_HEAP) { |
949 | 947 |
_delta2->push(vb, _blossom_set->classPrio(vb) - |
950 | 948 |
(*_blossom_data)[vb].offset); |
951 | 949 |
} else if ((*_delta2)[vb] > _blossom_set->classPrio(vb) - |
952 |
(*_blossom_data)[vb].offset){ |
|
953 |
_delta2->decrease(vb, _blossom_set->classPrio(vb) - |
|
954 |
(*_blossom_data)[vb].offset); |
|
955 |
} |
|
956 |
} |
|
957 |
} |
|
958 |
} |
|
959 |
} |
|
960 |
} |
|
961 |
(*_blossom_data)[blossom].offset = 0; |
|
962 |
} |
|
963 |
|
|
964 |
void matchedToOdd(int blossom) { |
|
965 |
if (_delta2->state(blossom) == _delta2->IN_HEAP) { |
|
966 |
_delta2->erase(blossom); |
|
967 |
} |
|
968 |
(*_blossom_data)[blossom].offset += _delta_sum; |
|
969 |
if (!_blossom_set->trivial(blossom)) { |
|
970 |
_delta4->push(blossom, (*_blossom_data)[blossom].pot / 2 + |
|
971 |
(*_blossom_data)[blossom].offset); |
|
972 |
} |
|
973 |
} |
|
974 |
|
|
975 |
void evenToMatched(int blossom, int tree) { |
|
976 |
if (!_blossom_set->trivial(blossom)) { |
|
977 |
(*_blossom_data)[blossom].pot += 2 * _delta_sum; |
|
978 |
} |
|
979 |
|
|
980 |
for (typename BlossomSet::ItemIt n(*_blossom_set, blossom); |
|
981 |
n != INVALID; ++n) { |
|
982 |
int ni = (*_node_index)[n]; |
|
983 |
(*_node_data)[ni].pot -= _delta_sum; |
|
984 |
|
|
985 |
_delta1->erase(n); |
|
986 |
|
|
987 |
for (InArcIt e(_graph, n); e != INVALID; ++e) { |
|
988 |
Node v = _graph.source(e); |
|
989 |
int vb = _blossom_set->find(v); |
|
990 |
int vi = (*_node_index)[v]; |
|
991 |
|
|
992 |
Value rw = (*_node_data)[ni].pot + (*_node_data)[vi].pot - |
|
993 |
dualScale * _weight[e]; |
|
994 |
|
|
995 |
if (vb == blossom) { |
|
996 |
if (_delta3->state(e) == _delta3->IN_HEAP) { |
|
997 |
_delta3->erase(e); |
|
998 |
} |
|
999 |
} else if ((*_blossom_data)[vb].status == EVEN) { |
|
1000 |
|
|
1001 |
if (_delta3->state(e) == _delta3->IN_HEAP) { |
|
1002 |
_delta3->erase(e); |
|
1003 |
} |
|
1004 |
|
|
1005 |
int vt = _tree_set->find(vb); |
|
1006 |
|
|
1007 |
if (vt != tree) { |
|
1008 |
|
|
1009 |
Arc r = _graph.oppositeArc(e); |
|
1010 |
|
|
1011 |
typename std::map<int, Arc>::iterator it = |
|
1012 |
(*_node_data)[ni].heap_index.find(vt); |
|
1013 |
|
|
1014 |
if (it != (*_node_data)[ni].heap_index.end()) { |
|
1015 |
if ((*_node_data)[ni].heap[it->second] > rw) { |
|
1016 |
(*_node_data)[ni].heap.replace(it->second, r); |
|
1017 |
(*_node_data)[ni].heap.decrease(r, rw); |
|
1018 |
it->second = r; |
|
1019 |
} |
|
1020 |
} else { |
|
1021 |
(*_node_data)[ni].heap.push(r, rw); |
|
1022 |
(*_node_data)[ni].heap_index.insert(std::make_pair(vt, r)); |
|
1023 |
} |
|
1024 |
|
|
1025 |
if ((*_blossom_set)[n] > (*_node_data)[ni].heap.prio()) { |
|
1026 |
_blossom_set->decrease(n, (*_node_data)[ni].heap.prio()); |
|
1027 |
|
|
1028 |
if (_delta2->state(blossom) != _delta2->IN_HEAP) { |
|
1029 |
_delta2->push(blossom, _blossom_set->classPrio(blossom) - |
|
1030 |
(*_blossom_data)[blossom].offset); |
|
1031 |
} else if ((*_delta2)[blossom] > |
|
1032 |
_blossom_set->classPrio(blossom) - |
|
1033 |
(*_blossom_data)[blossom].offset){ |
|
1034 |
_delta2->decrease(blossom, _blossom_set->classPrio(blossom) - |
|
1035 |
(*_blossom_data)[blossom].offset); |
|
1036 |
} |
|
1037 |
} |
|
1038 |
} |
|
1039 |
|
|
1040 |
} else if ((*_blossom_data)[vb].status == UNMATCHED) { |
|
1041 |
if (_delta3->state(e) == _delta3->IN_HEAP) { |
|
1042 |
_delta3->erase(e); |
|
1043 |
} |
|
1044 |
} else { |
|
1045 |
|
|
1046 |
typename std::map<int, Arc>::iterator it = |
|
1047 |
(*_node_data)[vi].heap_index.find(tree); |
|
1048 |
|
|
1049 |
if (it != (*_node_data)[vi].heap_index.end()) { |
|
1050 |
(*_node_data)[vi].heap.erase(it->second); |
|
1051 |
(*_node_data)[vi].heap_index.erase(it); |
|
1052 |
if ((*_node_data)[vi].heap.empty()) { |
|
1053 |
_blossom_set->increase(v, std::numeric_limits<Value>::max()); |
|
1054 |
} else if ((*_blossom_set)[v] < (*_node_data)[vi].heap.prio()) { |
|
1055 |
_blossom_set->increase(v, (*_node_data)[vi].heap.prio()); |
|
1056 |
} |
|
1057 |
|
|
1058 |
if ((*_blossom_data)[vb].status == MATCHED) { |
|
1059 |
if (_blossom_set->classPrio(vb) == |
|
1060 |
std::numeric_limits<Value>::max()) { |
|
1061 |
_delta2->erase(vb); |
|
1062 |
} else if ((*_delta2)[vb] < _blossom_set->classPrio(vb) - |
|
1063 |
(*_blossom_data)[vb].offset) { |
|
1064 |
_delta2->increase(vb, _blossom_set->classPrio(vb) - |
|
1065 |
(*_blossom_data)[vb].offset); |
|
1066 |
} |
|
1067 |
} |
|
1068 |
} |
|
1069 |
} |
|
1070 |
} |
|
1071 |
} |
|
1072 |
} |
|
1073 |
|
|
1074 |
void oddToMatched(int blossom) { |
|
1075 |
(*_blossom_data)[blossom].offset -= _delta_sum; |
|
1076 |
|
|
1077 |
if (_blossom_set->classPrio(blossom) != |
|
1078 |
std::numeric_limits<Value>::max()) { |
|
1079 |
_delta2->push(blossom, _blossom_set->classPrio(blossom) - |
|
1080 |
(*_blossom_data)[blossom].offset); |
|
1081 |
} |
|
1082 |
|
|
1083 |
if (!_blossom_set->trivial(blossom)) { |
|
1084 |
_delta4->erase(blossom); |
|
1085 |
} |
|
1086 |
} |
|
1087 |
|
|
1088 |
void oddToEven(int blossom, int tree) { |
|
1089 |
if (!_blossom_set->trivial(blossom)) { |
|
1090 |
_delta4->erase(blossom); |
|
1091 |
(*_blossom_data)[blossom].pot -= |
|
1092 |
2 * (2 * _delta_sum - (*_blossom_data)[blossom].offset); |
|
1093 |
} |
|
1094 |
|
|
1095 |
for (typename BlossomSet::ItemIt n(*_blossom_set, blossom); |
|
1096 |
n != INVALID; ++n) { |
|
1097 |
int ni = (*_node_index)[n]; |
|
1098 |
|
|
1099 |
_blossom_set->increase(n, std::numeric_limits<Value>::max()); |
|
1100 |
|
|
1101 |
(*_node_data)[ni].heap.clear(); |
|
1102 |
(*_node_data)[ni].heap_index.clear(); |
|
1103 |
(*_node_data)[ni].pot += |
|
1104 |
2 * _delta_sum - (*_blossom_data)[blossom].offset; |
|
1105 |
|
|
1106 |
_delta1->push(n, (*_node_data)[ni].pot); |
|
1107 |
|
|
1108 |
for (InArcIt e(_graph, n); e != INVALID; ++e) { |
|
1109 |
Node v = _graph.source(e); |
|
1110 |
int vb = _blossom_set->find(v); |
|
1111 |
int vi = (*_node_index)[v]; |
|
1112 |
|
|
1113 |
Value rw = (*_node_data)[ni].pot + (*_node_data)[vi].pot - |
|
1114 |
dualScale * _weight[e]; |
|
1115 |
|
|
1116 |
if ((*_blossom_data)[vb].status == EVEN) { |
|
1117 |
if (_delta3->state(e) != _delta3->IN_HEAP && blossom != vb) { |
|
1118 |
_delta3->push(e, rw / 2); |
|
1119 |
} |
|
1120 |
} else if ((*_blossom_data)[vb].status == UNMATCHED) { |
|
1121 |
if (_delta3->state(e) != _delta3->IN_HEAP) { |
|
1122 |
_delta3->push(e, rw); |
|
1123 |
} |
|
1124 |
} else { |
|
1125 |
|
|
1126 |
typename std::map<int, Arc>::iterator it = |
|
1127 |
(*_node_data)[vi].heap_index.find(tree); |
|
1128 |
|
|
1129 |
if (it != (*_node_data)[vi].heap_index.end()) { |
|
1130 |
if ((*_node_data)[vi].heap[it->second] > rw) { |
|
1131 |
(*_node_data)[vi].heap.replace(it->second, e); |
|
1132 |
(*_node_data)[vi].heap.decrease(e, rw); |
|
1133 |
it->second = e; |
|
1134 |
} |
|
1135 |
} else { |
|
1136 |
(*_node_data)[vi].heap.push(e, rw); |
|
1137 |
(*_node_data)[vi].heap_index.insert(std::make_pair(tree, e)); |
|
1138 |
} |
|
1139 |
|
|
1140 |
if ((*_blossom_set)[v] > (*_node_data)[vi].heap.prio()) { |
|
1141 |
_blossom_set->decrease(v, (*_node_data)[vi].heap.prio()); |
|
1142 |
|
|
1143 |
if ((*_blossom_data)[vb].status == MATCHED) { |
|
1144 |
if (_delta2->state(vb) != _delta2->IN_HEAP) { |
|
1145 |
_delta2->push(vb, _blossom_set->classPrio(vb) - |
|
1146 |
(*_blossom_data)[vb].offset); |
|
1147 |
} else if ((*_delta2)[vb] > _blossom_set->classPrio(vb) - |
|
1148 | 950 |
(*_blossom_data)[vb].offset) { |
1149 | 951 |
_delta2->decrease(vb, _blossom_set->classPrio(vb) - |
1150 | 952 |
(*_blossom_data)[vb].offset); |
1151 | 953 |
} |
1152 | 954 |
} |
1153 | 955 |
} |
1154 | 956 |
} |
1155 | 957 |
} |
1156 | 958 |
} |
1157 | 959 |
(*_blossom_data)[blossom].offset = 0; |
1158 | 960 |
} |
1159 | 961 |
|
1160 |
|
|
1161 |
void matchedToUnmatched(int blossom) { |
|
962 |
void matchedToOdd(int blossom) { |
|
1162 | 963 |
if (_delta2->state(blossom) == _delta2->IN_HEAP) { |
1163 | 964 |
_delta2->erase(blossom); |
1164 | 965 |
} |
966 |
(*_blossom_data)[blossom].offset += _delta_sum; |
|
967 |
if (!_blossom_set->trivial(blossom)) { |
|
968 |
_delta4->push(blossom, (*_blossom_data)[blossom].pot / 2 + |
|
969 |
(*_blossom_data)[blossom].offset); |
|
970 |
} |
|
971 |
} |
|
972 |
|
|
973 |
void evenToMatched(int blossom, int tree) { |
|
974 |
if (!_blossom_set->trivial(blossom)) { |
|
975 |
(*_blossom_data)[blossom].pot += 2 * _delta_sum; |
|
976 |
} |
|
1165 | 977 |
|
1166 | 978 |
for (typename BlossomSet::ItemIt n(*_blossom_set, blossom); |
1167 | 979 |
n != INVALID; ++n) { |
1168 | 980 |
int ni = (*_node_index)[n]; |
1169 |
|
|
1170 |
_blossom_set->increase(n, std::numeric_limits<Value>::max()); |
|
1171 |
|
|
1172 |
(*_node_data)[ni].heap.clear(); |
|
1173 |
(*_node_data)[ni].heap_index.clear(); |
|
1174 |
|
|
1175 |
for (OutArcIt e(_graph, n); e != INVALID; ++e) { |
|
1176 |
Node v = _graph.target(e); |
|
981 |
(*_node_data)[ni].pot -= _delta_sum; |
|
982 |
|
|
983 |
_delta1->erase(n); |
|
984 |
|
|
985 |
for (InArcIt e(_graph, n); e != INVALID; ++e) { |
|
986 |
Node v = _graph.source(e); |
|
1177 | 987 |
int vb = _blossom_set->find(v); |
1178 | 988 |
int vi = (*_node_index)[v]; |
1179 | 989 |
|
1180 | 990 |
Value rw = (*_node_data)[ni].pot + (*_node_data)[vi].pot - |
1181 | 991 |
dualScale * _weight[e]; |
1182 | 992 |
|
1183 |
if ((*_blossom_data)[vb].status == EVEN) { |
|
1184 |
if (_delta3->state(e) != _delta3->IN_HEAP) { |
|
1185 |
|
|
993 |
if (vb == blossom) { |
|
994 |
if (_delta3->state(e) == _delta3->IN_HEAP) { |
|
995 |
_delta3->erase(e); |
|
996 |
} |
|
997 |
} else if ((*_blossom_data)[vb].status == EVEN) { |
|
998 |
|
|
999 |
if (_delta3->state(e) == _delta3->IN_HEAP) { |
|
1000 |
_delta3->erase(e); |
|
1001 |
} |
|
1002 |
|
|
1003 |
int vt = _tree_set->find(vb); |
|
1004 |
|
|
1005 |
if (vt != tree) { |
|
1006 |
|
|
1007 |
Arc r = _graph.oppositeArc(e); |
|
1008 |
|
|
1009 |
typename std::map<int, Arc>::iterator it = |
|
1010 |
(*_node_data)[ni].heap_index.find(vt); |
|
1011 |
|
|
1012 |
if (it != (*_node_data)[ni].heap_index.end()) { |
|
1013 |
if ((*_node_data)[ni].heap[it->second] > rw) { |
|
1014 |
(*_node_data)[ni].heap.replace(it->second, r); |
|
1015 |
(*_node_data)[ni].heap.decrease(r, rw); |
|
1016 |
it->second = r; |
|
1017 |
} |
|
1018 |
} else { |
|
1019 |
(*_node_data)[ni].heap.push(r, rw); |
|
1020 |
(*_node_data)[ni].heap_index.insert(std::make_pair(vt, r)); |
|
1021 |
} |
|
1022 |
|
|
1023 |
if ((*_blossom_set)[n] > (*_node_data)[ni].heap.prio()) { |
|
1024 |
_blossom_set->decrease(n, (*_node_data)[ni].heap.prio()); |
|
1025 |
|
|
1026 |
if (_delta2->state(blossom) != _delta2->IN_HEAP) { |
|
1027 |
_delta2->push(blossom, _blossom_set->classPrio(blossom) - |
|
1028 |
(*_blossom_data)[blossom].offset); |
|
1029 |
} else if ((*_delta2)[blossom] > |
|
1030 |
_blossom_set->classPrio(blossom) - |
|
1031 |
(*_blossom_data)[blossom].offset){ |
|
1032 |
_delta2->decrease(blossom, _blossom_set->classPrio(blossom) - |
|
1033 |
(*_blossom_data)[blossom].offset); |
|
1034 |
} |
|
1035 |
} |
|
1036 |
} |
|
1037 |
} else { |
|
1038 |
|
|
1039 |
typename std::map<int, Arc>::iterator it = |
|
1040 |
(*_node_data)[vi].heap_index.find(tree); |
|
1041 |
|
|
1042 |
if (it != (*_node_data)[vi].heap_index.end()) { |
|
1043 |
(*_node_data)[vi].heap.erase(it->second); |
|
1044 |
(*_node_data)[vi].heap_index.erase(it); |
|
1045 |
if ((*_node_data)[vi].heap.empty()) { |
|
1046 |
_blossom_set->increase(v, std::numeric_limits<Value>::max()); |
|
1047 |
} else if ((*_blossom_set)[v] < (*_node_data)[vi].heap.prio()) { |
|
1048 |
_blossom_set->increase(v, (*_node_data)[vi].heap.prio()); |
|
1049 |
} |
|
1050 |
|
|
1051 |
if ((*_blossom_data)[vb].status == MATCHED) { |
|
1052 |
if (_blossom_set->classPrio(vb) == |
|
1053 |
std::numeric_limits<Value>::max()) { |
|
1054 |
_delta2->erase(vb); |
|
1055 |
} else if ((*_delta2)[vb] < _blossom_set->classPrio(vb) - |
|
1056 |
(*_blossom_data)[vb].offset) { |
|
1057 |
_delta2->increase(vb, _blossom_set->classPrio(vb) - |
|
1058 |
(*_blossom_data)[vb].offset); |
|
1059 |
} |
|
1060 |
} |
|
1186 | 1061 |
} |
1187 | 1062 |
} |
1188 | 1063 |
} |
1189 | 1064 |
} |
1190 | 1065 |
} |
1191 | 1066 |
|
1192 |
void |
|
1067 |
void oddToMatched(int blossom) { |
|
1068 |
(*_blossom_data)[blossom].offset -= _delta_sum; |
|
1069 |
|
|
1070 |
if (_blossom_set->classPrio(blossom) != |
|
1071 |
std::numeric_limits<Value>::max()) { |
|
1072 |
_delta2->push(blossom, _blossom_set->classPrio(blossom) - |
|
1073 |
(*_blossom_data)[blossom].offset); |
|
1074 |
} |
|
1075 |
|
|
1076 |
if (!_blossom_set->trivial(blossom)) { |
|
1077 |
_delta4->erase(blossom); |
|
1078 |
} |
|
1079 |
} |
|
1080 |
|
|
1081 |
void oddToEven(int blossom, int tree) { |
|
1082 |
if (!_blossom_set->trivial(blossom)) { |
|
1083 |
_delta4->erase(blossom); |
|
1084 |
(*_blossom_data)[blossom].pot -= |
|
1085 |
2 * (2 * _delta_sum - (*_blossom_data)[blossom].offset); |
|
1086 |
} |
|
1087 |
|
|
1193 | 1088 |
for (typename BlossomSet::ItemIt n(*_blossom_set, blossom); |
1194 | 1089 |
n != INVALID; ++n) { |
1195 | 1090 |
int ni = (*_node_index)[n]; |
1196 | 1091 |
|
1092 |
_blossom_set->increase(n, std::numeric_limits<Value>::max()); |
|
1093 |
|
|
1094 |
(*_node_data)[ni].heap.clear(); |
|
1095 |
(*_node_data)[ni].heap_index.clear(); |
|
1096 |
(*_node_data)[ni].pot += |
|
1097 |
2 * _delta_sum - (*_blossom_data)[blossom].offset; |
|
1098 |
|
|
1099 |
_delta1->push(n, (*_node_data)[ni].pot); |
|
1100 |
|
|
1197 | 1101 |
for (InArcIt e(_graph, n); e != INVALID; ++e) { |
1198 | 1102 |
Node v = _graph.source(e); |
1199 | 1103 |
int vb = _blossom_set->find(v); |
1200 | 1104 |
int vi = (*_node_index)[v]; |
1201 | 1105 |
|
1202 | 1106 |
Value rw = (*_node_data)[ni].pot + (*_node_data)[vi].pot - |
1203 | 1107 |
dualScale * _weight[e]; |
1204 | 1108 |
|
1205 |
if (vb == blossom) { |
|
1206 |
if (_delta3->state(e) == _delta3->IN_HEAP) { |
|
1207 |
|
|
1109 |
if ((*_blossom_data)[vb].status == EVEN) { |
|
1110 |
if (_delta3->state(e) != _delta3->IN_HEAP && blossom != vb) { |
|
1111 |
_delta3->push(e, rw / 2); |
|
1208 | 1112 |
} |
1209 |
} else if ((*_blossom_data)[vb].status == EVEN) { |
|
1210 |
|
|
1211 |
if (_delta3->state(e) == _delta3->IN_HEAP) { |
|
1212 |
_delta3->erase(e); |
|
1213 |
} |
|
1214 |
|
|
1215 |
int vt = _tree_set->find(vb); |
|
1216 |
|
|
1217 |
|
|
1113 |
} else { |
|
1218 | 1114 |
|
1219 | 1115 |
typename std::map<int, Arc>::iterator it = |
1220 |
(*_node_data)[ni].heap_index.find(vt); |
|
1221 |
|
|
1222 |
if (it != (*_node_data)[ni].heap_index.end()) { |
|
1223 |
if ((*_node_data)[ni].heap[it->second] > rw) { |
|
1224 |
(*_node_data)[ni].heap.replace(it->second, r); |
|
1225 |
(*_node_data)[ni].heap.decrease(r, rw); |
|
1226 |
|
|
1116 |
(*_node_data)[vi].heap_index.find(tree); |
|
1117 |
|
|
1118 |
if (it != (*_node_data)[vi].heap_index.end()) { |
|
1119 |
if ((*_node_data)[vi].heap[it->second] > rw) { |
|
1120 |
(*_node_data)[vi].heap.replace(it->second, e); |
|
1121 |
(*_node_data)[vi].heap.decrease(e, rw); |
|
1122 |
it->second = e; |
|
1227 | 1123 |
} |
1228 | 1124 |
} else { |
1229 |
(*_node_data)[ni].heap.push(r, rw); |
|
1230 |
(*_node_data)[ni].heap_index.insert(std::make_pair(vt, r)); |
|
1125 |
(*_node_data)[vi].heap.push(e, rw); |
|
1126 |
(*_node_data)[vi].heap_index.insert(std::make_pair(tree, e)); |
|
1231 | 1127 |
} |
1232 | 1128 |
|
1233 |
if ((*_blossom_set)[n] > (*_node_data)[ni].heap.prio()) { |
|
1234 |
_blossom_set->decrease(n, (*_node_data)[ni].heap.prio()); |
|
1235 |
|
|
1236 |
if (_delta2->state(blossom) != _delta2->IN_HEAP) { |
|
1237 |
_delta2->push(blossom, _blossom_set->classPrio(blossom) - |
|
1238 |
(*_blossom_data)[blossom].offset); |
|
1239 |
} else if ((*_delta2)[blossom] > _blossom_set->classPrio(blossom)- |
|
1240 |
(*_blossom_data)[blossom].offset){ |
|
1241 |
_delta2->decrease(blossom, _blossom_set->classPrio(blossom) - |
|
1242 |
(*_blossom_data)[blossom].offset); |
|
1129 |
if ((*_blossom_set)[v] > (*_node_data)[vi].heap.prio()) { |
|
1130 |
_blossom_set->decrease(v, (*_node_data)[vi].heap.prio()); |
|
1131 |
|
|
1132 |
if ((*_blossom_data)[vb].status == MATCHED) { |
|
1133 |
if (_delta2->state(vb) != _delta2->IN_HEAP) { |
|
1134 |
_delta2->push(vb, _blossom_set->classPrio(vb) - |
|
1135 |
(*_blossom_data)[vb].offset); |
|
1136 |
} else if ((*_delta2)[vb] > _blossom_set->classPrio(vb) - |
|
1137 |
(*_blossom_data)[vb].offset) { |
|
1138 |
_delta2->decrease(vb, _blossom_set->classPrio(vb) - |
|
1139 |
(*_blossom_data)[vb].offset); |
|
1140 |
} |
|
1243 | 1141 |
} |
1244 | 1142 |
} |
1245 |
|
|
1246 |
} else if ((*_blossom_data)[vb].status == UNMATCHED) { |
|
1247 |
if (_delta3->state(e) == _delta3->IN_HEAP) { |
|
1248 |
_delta3->erase(e); |
|
1249 |
} |
|
1250 | 1143 |
} |
1251 | 1144 |
} |
1252 | 1145 |
} |
1146 |
(*_blossom_data)[blossom].offset = 0; |
|
1253 | 1147 |
} |
1254 | 1148 |
|
1255 | 1149 |
void alternatePath(int even, int tree) { |
1256 | 1150 |
int odd; |
1257 | 1151 |
|
1258 | 1152 |
evenToMatched(even, tree); |
... | ... |
@@ -1291,45 +1185,48 @@ |
1291 | 1185 |
int blossom = _blossom_set->find(node); |
1292 | 1186 |
int tree = _tree_set->find(blossom); |
1293 | 1187 |
|
1294 | 1188 |
alternatePath(blossom, tree); |
1295 | 1189 |
destroyTree(tree); |
1296 | 1190 |
|
1297 |
(*_blossom_data)[blossom].status = UNMATCHED; |
|
1298 | 1191 |
(*_blossom_data)[blossom].base = node; |
1299 |
|
|
1192 |
(*_blossom_data)[blossom].next = INVALID; |
|
1300 | 1193 |
} |
1301 | 1194 |
|
1302 |
|
|
1303 | 1195 |
void augmentOnEdge(const Edge& edge) { |
1304 | 1196 |
|
1305 | 1197 |
int left = _blossom_set->find(_graph.u(edge)); |
1306 | 1198 |
int right = _blossom_set->find(_graph.v(edge)); |
1307 | 1199 |
|
1308 |
if ((*_blossom_data)[left].status == EVEN) { |
|
1309 |
int left_tree = _tree_set->find(left); |
|
1310 |
alternatePath(left, left_tree); |
|
1311 |
destroyTree(left_tree); |
|
1312 |
} else { |
|
1313 |
(*_blossom_data)[left].status = MATCHED; |
|
1314 |
unmatchedToMatched(left); |
|
1315 |
} |
|
1316 |
|
|
1317 |
if ((*_blossom_data)[right].status == EVEN) { |
|
1318 |
int right_tree = _tree_set->find(right); |
|
1319 |
alternatePath(right, right_tree); |
|
1320 |
destroyTree(right_tree); |
|
1321 |
} else { |
|
1322 |
(*_blossom_data)[right].status = MATCHED; |
|
1323 |
unmatchedToMatched(right); |
|
1324 |
|
|
1200 |
int left_tree = _tree_set->find(left); |
|
1201 |
alternatePath(left, left_tree); |
|
1202 |
destroyTree(left_tree); |
|
1203 |
|
|
1204 |
int right_tree = _tree_set->find(right); |
|
1205 |
alternatePath(right, right_tree); |
|
1206 |
destroyTree(right_tree); |
|
1325 | 1207 |
|
1326 | 1208 |
(*_blossom_data)[left].next = _graph.direct(edge, true); |
1327 | 1209 |
(*_blossom_data)[right].next = _graph.direct(edge, false); |
1328 | 1210 |
} |
1329 | 1211 |
|
1212 |
void augmentOnArc(const Arc& arc) { |
|
1213 |
|
|
1214 |
int left = _blossom_set->find(_graph.source(arc)); |
|
1215 |
int right = _blossom_set->find(_graph.target(arc)); |
|
1216 |
|
|
1217 |
(*_blossom_data)[left].status = MATCHED; |
|
1218 |
|
|
1219 |
int right_tree = _tree_set->find(right); |
|
1220 |
alternatePath(right, right_tree); |
|
1221 |
destroyTree(right_tree); |
|
1222 |
|
|
1223 |
(*_blossom_data)[left].next = arc; |
|
1224 |
(*_blossom_data)[right].next = _graph.oppositeArc(arc); |
|
1225 |
} |
|
1226 |
|
|
1330 | 1227 |
void extendOnArc(const Arc& arc) { |
1331 | 1228 |
int base = _blossom_set->find(_graph.target(arc)); |
1332 | 1229 |
int tree = _tree_set->find(base); |
1333 | 1230 |
|
1334 | 1231 |
int odd = _blossom_set->find(_graph.source(arc)); |
1335 | 1232 |
_tree_set->insert(odd, tree); |
... | ... |
@@ -1526,13 +1423,13 @@ |
1526 | 1423 |
|
1527 | 1424 |
(*_blossom_data)[sb].status = ODD; |
1528 | 1425 |
matchedToOdd(sb); |
1529 | 1426 |
_tree_set->insert(sb, tree); |
1530 | 1427 |
(*_blossom_data)[sb].pred = pred; |
1531 | 1428 |
(*_blossom_data)[sb].next = |
1532 |
|
|
1429 |
_graph.oppositeArc((*_blossom_data)[tb].next); |
|
1533 | 1430 |
|
1534 | 1431 |
pred = (*_blossom_data)[ub].next; |
1535 | 1432 |
|
1536 | 1433 |
(*_blossom_data)[tb].status = EVEN; |
1537 | 1434 |
matchedToEven(tb, tree); |
1538 | 1435 |
_tree_set->insert(tb, tree); |
... | ... |
@@ -1626,13 +1523,13 @@ |
1626 | 1523 |
std::vector<int> blossoms; |
1627 | 1524 |
for (typename BlossomSet::ClassIt c(*_blossom_set); c != INVALID; ++c) { |
1628 | 1525 |
blossoms.push_back(c); |
1629 | 1526 |
} |
1630 | 1527 |
|
1631 | 1528 |
for (int i = 0; i < int(blossoms.size()); ++i) { |
1632 |
if ((*_blossom_data)[blossoms[i]]. |
|
1529 |
if ((*_blossom_data)[blossoms[i]].next != INVALID) { |
|
1633 | 1530 |
|
1634 | 1531 |
Value offset = (*_blossom_data)[blossoms[i]].offset; |
1635 | 1532 |
(*_blossom_data)[blossoms[i]].pot += 2 * offset; |
1636 | 1533 |
for (typename BlossomSet::ItemIt n(*_blossom_set, blossoms[i]); |
1637 | 1534 |
n != INVALID; ++n) { |
1638 | 1535 |
(*_node_data)[(*_node_index)[n]].pot -= offset; |
... | ... |
@@ -1664,16 +1561,22 @@ |
1664 | 1561 |
|
1665 | 1562 |
_delta1_index(0), _delta1(0), |
1666 | 1563 |
_delta2_index(0), _delta2(0), |
1667 | 1564 |
_delta3_index(0), _delta3(0), |
1668 | 1565 |
_delta4_index(0), _delta4(0), |
1669 | 1566 |
|
1670 |
_delta_sum() |
|
1567 |
_delta_sum(), _unmatched(0), |
|
1568 |
|
|
1569 |
_fractional(0) |
|
1570 |
{} |
|
1671 | 1571 |
|
1672 | 1572 |
~MaxWeightedMatching() { |
1673 | 1573 |
destroyStructures(); |
1574 |
if (_fractional) { |
|
1575 |
delete _fractional; |
|
1576 |
} |
|
1674 | 1577 |
} |
1675 | 1578 |
|
1676 | 1579 |
/// \name Execution Control |
1677 | 1580 |
/// The simplest way to execute the algorithm is to use the |
1678 | 1581 |
/// \ref run() member function. |
1679 | 1582 |
|
... | ... |
@@ -1696,12 +1599,14 @@ |
1696 | 1599 |
} |
1697 | 1600 |
for (int i = 0; i < _blossom_num; ++i) { |
1698 | 1601 |
(*_delta2_index)[i] = _delta2->PRE_HEAP; |
1699 | 1602 |
(*_delta4_index)[i] = _delta4->PRE_HEAP; |
1700 | 1603 |
} |
1701 | 1604 |
|
1605 |
_unmatched = _node_num; |
|
1606 |
|
|
1702 | 1607 |
int index = 0; |
1703 | 1608 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
1704 | 1609 |
Value max = 0; |
1705 | 1610 |
for (OutArcIt e(_graph, n); e != INVALID; ++e) { |
1706 | 1611 |
if (_graph.target(e) == n) continue; |
1707 | 1612 |
if ((dualScale * _weight[e]) / 2 > max) { |
... | ... |
@@ -1730,88 +1635,217 @@ |
1730 | 1635 |
_delta3->push(e, ((*_node_data)[si].pot + (*_node_data)[ti].pot - |
1731 | 1636 |
dualScale * _weight[e]) / 2); |
1732 | 1637 |
} |
1733 | 1638 |
} |
1734 | 1639 |
} |
1735 | 1640 |
|
1641 |
/// \brief Initialize the algorithm with fractional matching |
|
1642 |
/// |
|
1643 |
/// This function initializes the algorithm with a fractional |
|
1644 |
/// matching. This initialization is also called jumpstart heuristic. |
|
1645 |
void fractionalInit() { |
|
1646 |
createStructures(); |
|
1647 |
|
|
1648 |
if (_fractional == 0) { |
|
1649 |
_fractional = new FractionalMatching(_graph, _weight, false); |
|
1650 |
} |
|
1651 |
_fractional->run(); |
|
1652 |
|
|
1653 |
for (ArcIt e(_graph); e != INVALID; ++e) { |
|
1654 |
(*_node_heap_index)[e] = BinHeap<Value, IntArcMap>::PRE_HEAP; |
|
1655 |
} |
|
1656 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
1657 |
(*_delta1_index)[n] = _delta1->PRE_HEAP; |
|
1658 |
} |
|
1659 |
for (EdgeIt e(_graph); e != INVALID; ++e) { |
|
1660 |
(*_delta3_index)[e] = _delta3->PRE_HEAP; |
|
1661 |
} |
|
1662 |
for (int i = 0; i < _blossom_num; ++i) { |
|
1663 |
(*_delta2_index)[i] = _delta2->PRE_HEAP; |
|
1664 |
(*_delta4_index)[i] = _delta4->PRE_HEAP; |
|
1665 |
} |
|
1666 |
|
|
1667 |
_unmatched = 0; |
|
1668 |
|
|
1669 |
int index = 0; |
|
1670 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
1671 |
Value pot = _fractional->nodeValue(n); |
|
1672 |
(*_node_index)[n] = index; |
|
1673 |
(*_node_data)[index].pot = pot; |
|
1674 |
int blossom = |
|
1675 |
_blossom_set->insert(n, std::numeric_limits<Value>::max()); |
|
1676 |
|
|
1677 |
(*_blossom_data)[blossom].status = MATCHED; |
|
1678 |
(*_blossom_data)[blossom].pred = INVALID; |
|
1679 |
(*_blossom_data)[blossom].next = _fractional->matching(n); |
|
1680 |
if (_fractional->matching(n) == INVALID) { |
|
1681 |
(*_blossom_data)[blossom].base = n; |
|
1682 |
} |
|
1683 |
(*_blossom_data)[blossom].pot = 0; |
|
1684 |
(*_blossom_data)[blossom].offset = 0; |
|
1685 |
++index; |
|
1686 |
} |
|
1687 |
|
|
1688 |
typename Graph::template NodeMap<bool> processed(_graph, false); |
|
1689 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
1690 |
if (processed[n]) continue; |
|
1691 |
processed[n] = true; |
|
1692 |
if (_fractional->matching(n) == INVALID) continue; |
|
1693 |
int num = 1; |
|
1694 |
Node v = _graph.target(_fractional->matching(n)); |
|
1695 |
while (n != v) { |
|
1696 |
processed[v] = true; |
|
1697 |
v = _graph.target(_fractional->matching(v)); |
|
1698 |
++num; |
|
1699 |
} |
|
1700 |
|
|
1701 |
if (num % 2 == 1) { |
|
1702 |
std::vector<int> subblossoms(num); |
|
1703 |
|
|
1704 |
subblossoms[--num] = _blossom_set->find(n); |
|
1705 |
_delta1->push(n, _fractional->nodeValue(n)); |
|
1706 |
v = _graph.target(_fractional->matching(n)); |
|
1707 |
while (n != v) { |
|
1708 |
subblossoms[--num] = _blossom_set->find(v); |
|
1709 |
_delta1->push(v, _fractional->nodeValue(v)); |
|
1710 |
v = _graph.target(_fractional->matching(v)); |
|
1711 |
} |
|
1712 |
|
|
1713 |
int surface = |
|
1714 |
_blossom_set->join(subblossoms.begin(), subblossoms.end()); |
|
1715 |
(*_blossom_data)[surface].status = EVEN; |
|
1716 |
(*_blossom_data)[surface].pred = INVALID; |
|
1717 |
(*_blossom_data)[surface].next = INVALID; |
|
1718 |
(*_blossom_data)[surface].pot = 0; |
|
1719 |
(*_blossom_data)[surface].offset = 0; |
|
1720 |
|
|
1721 |
_tree_set->insert(surface); |
|
1722 |
++_unmatched; |
|
1723 |
} |
|
1724 |
} |
|
1725 |
|
|
1726 |
for (EdgeIt e(_graph); e != INVALID; ++e) { |
|
1727 |
int si = (*_node_index)[_graph.u(e)]; |
|
1728 |
int sb = _blossom_set->find(_graph.u(e)); |
|
1729 |
int ti = (*_node_index)[_graph.v(e)]; |
|
1730 |
int tb = _blossom_set->find(_graph.v(e)); |
|
1731 |
if ((*_blossom_data)[sb].status == EVEN && |
|
1732 |
(*_blossom_data)[tb].status == EVEN && sb != tb) { |
|
1733 |
_delta3->push(e, ((*_node_data)[si].pot + (*_node_data)[ti].pot - |
|
1734 |
dualScale * _weight[e]) / 2); |
|
1735 |
} |
|
1736 |
} |
|
1737 |
|
|
1738 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
1739 |
int nb = _blossom_set->find(n); |
|
1740 |
if ((*_blossom_data)[nb].status != MATCHED) continue; |
|
1741 |
int ni = (*_node_index)[n]; |
|
1742 |
|
|
1743 |
for (OutArcIt e(_graph, n); e != INVALID; ++e) { |
|
1744 |
Node v = _graph.target(e); |
|
1745 |
int vb = _blossom_set->find(v); |
|
1746 |
int vi = (*_node_index)[v]; |
|
1747 |
|
|
1748 |
Value rw = (*_node_data)[ni].pot + (*_node_data)[vi].pot - |
|
1749 |
dualScale * _weight[e]; |
|
1750 |
|
|
1751 |
if ((*_blossom_data)[vb].status == EVEN) { |
|
1752 |
|
|
1753 |
int vt = _tree_set->find(vb); |
|
1754 |
|
|
1755 |
typename std::map<int, Arc>::iterator it = |
|
1756 |
(*_node_data)[ni].heap_index.find(vt); |
|
1757 |
|
|
1758 |
if (it != (*_node_data)[ni].heap_index.end()) { |
|
1759 |
if ((*_node_data)[ni].heap[it->second] > rw) { |
|
1760 |
(*_node_data)[ni].heap.replace(it->second, e); |
|
1761 |
(*_node_data)[ni].heap.decrease(e, rw); |
|
1762 |
it->second = e; |
|
1763 |
} |
|
1764 |
} else { |
|
1765 |
(*_node_data)[ni].heap.push(e, rw); |
|
1766 |
(*_node_data)[ni].heap_index.insert(std::make_pair(vt, e)); |
|
1767 |
} |
|
1768 |
} |
|
1769 |
} |
|
1770 |
|
|
1771 |
if (!(*_node_data)[ni].heap.empty()) { |
|
1772 |
_blossom_set->decrease(n, (*_node_data)[ni].heap.prio()); |
|
1773 |
_delta2->push(nb, _blossom_set->classPrio(nb)); |
|
1774 |
} |
|
1775 |
} |
|
1776 |
} |
|
1777 |
|
|
1736 | 1778 |
/// \brief Start the algorithm |
1737 | 1779 |
/// |
1738 | 1780 |
/// This function starts the algorithm. |
1739 | 1781 |
/// |
1740 |
/// \pre \ref init() must be called |
|
1782 |
/// \pre \ref init() or \ref fractionalInit() must be called |
|
1783 |
/// before using this function. |
|
1741 | 1784 |
void start() { |
1742 | 1785 |
enum OpType { |
1743 | 1786 |
D1, D2, D3, D4 |
1744 | 1787 |
}; |
1745 | 1788 |
|
1746 |
int unmatched = _node_num; |
|
1747 |
while (unmatched > 0) { |
|
1789 |
while (_unmatched > 0) { |
|
1748 | 1790 |
Value d1 = !_delta1->empty() ? |
1749 | 1791 |
_delta1->prio() : std::numeric_limits<Value>::max(); |
1750 | 1792 |
|
1751 | 1793 |
Value d2 = !_delta2->empty() ? |
1752 | 1794 |
_delta2->prio() : std::numeric_limits<Value>::max(); |
1753 | 1795 |
|
1754 | 1796 |
Value d3 = !_delta3->empty() ? |
1755 | 1797 |
_delta3->prio() : std::numeric_limits<Value>::max(); |
1756 | 1798 |
|
1757 | 1799 |
Value d4 = !_delta4->empty() ? |
1758 | 1800 |
_delta4->prio() : std::numeric_limits<Value>::max(); |
1759 | 1801 |
|
1760 |
_delta_sum = |
|
1802 |
_delta_sum = d3; OpType ot = D3; |
|
1803 |
if (d1 < _delta_sum) { _delta_sum = d1; ot = D1; } |
|
1761 | 1804 |
if (d2 < _delta_sum) { _delta_sum = d2; ot = D2; } |
1762 |
if (d3 < _delta_sum) { _delta_sum = d3; ot = D3; } |
|
1763 | 1805 |
if (d4 < _delta_sum) { _delta_sum = d4; ot = D4; } |
1764 | 1806 |
|
1765 |
|
|
1766 | 1807 |
switch (ot) { |
1767 | 1808 |
case D1: |
1768 | 1809 |
{ |
1769 | 1810 |
Node n = _delta1->top(); |
1770 | 1811 |
unmatchNode(n); |
1771 |
-- |
|
1812 |
--_unmatched; |
|
1772 | 1813 |
} |
1773 | 1814 |
break; |
1774 | 1815 |
case D2: |
1775 | 1816 |
{ |
1776 | 1817 |
int blossom = _delta2->top(); |
1777 | 1818 |
Node n = _blossom_set->classTop(blossom); |
1778 |
Arc e = (*_node_data)[(*_node_index)[n]].heap.top(); |
|
1779 |
extendOnArc(e); |
|
1819 |
Arc a = (*_node_data)[(*_node_index)[n]].heap.top(); |
|
1820 |
if ((*_blossom_data)[blossom].next == INVALID) { |
|
1821 |
augmentOnArc(a); |
|
1822 |
--_unmatched; |
|
1823 |
} else { |
|
1824 |
extendOnArc(a); |
|
1825 |
} |
|
1780 | 1826 |
} |
1781 | 1827 |
break; |
1782 | 1828 |
case D3: |
1783 | 1829 |
{ |
1784 | 1830 |
Edge e = _delta3->top(); |
1785 | 1831 |
|
1786 | 1832 |
int left_blossom = _blossom_set->find(_graph.u(e)); |
1787 | 1833 |
int right_blossom = _blossom_set->find(_graph.v(e)); |
1788 | 1834 |
|
1789 | 1835 |
if (left_blossom == right_blossom) { |
1790 | 1836 |
_delta3->pop(); |
1791 | 1837 |
} else { |
1792 |
int left_tree; |
|
1793 |
if ((*_blossom_data)[left_blossom].status == EVEN) { |
|
1794 |
left_tree = _tree_set->find(left_blossom); |
|
1795 |
} else { |
|
1796 |
left_tree = -1; |
|
1797 |
++unmatched; |
|
1798 |
} |
|
1799 |
int right_tree; |
|
1800 |
if ((*_blossom_data)[right_blossom].status == EVEN) { |
|
1801 |
right_tree = _tree_set->find(right_blossom); |
|
1802 |
} else { |
|
1803 |
right_tree = -1; |
|
1804 |
++unmatched; |
|
1805 |
} |
|
1838 |
int left_tree = _tree_set->find(left_blossom); |
|
1839 |
int right_tree = _tree_set->find(right_blossom); |
|
1806 | 1840 |
|
1807 | 1841 |
if (left_tree == right_tree) { |
1808 | 1842 |
shrinkOnEdge(e, left_tree); |
1809 | 1843 |
} else { |
1810 | 1844 |
augmentOnEdge(e); |
1811 |
|
|
1845 |
_unmatched -= 2; |
|
1812 | 1846 |
} |
1813 | 1847 |
} |
1814 | 1848 |
} break; |
1815 | 1849 |
case D4: |
1816 | 1850 |
splitBlossom(_delta4->top()); |
1817 | 1851 |
break; |
... | ... |
@@ -1823,24 +1857,24 @@ |
1823 | 1857 |
/// \brief Run the algorithm. |
1824 | 1858 |
/// |
1825 | 1859 |
/// This method runs the \c %MaxWeightedMatching algorithm. |
1826 | 1860 |
/// |
1827 | 1861 |
/// \note mwm.run() is just a shortcut of the following code. |
1828 | 1862 |
/// \code |
1829 |
/// mwm. |
|
1863 |
/// mwm.fractionalInit(); |
|
1830 | 1864 |
/// mwm.start(); |
1831 | 1865 |
/// \endcode |
1832 | 1866 |
void run() { |
1833 |
|
|
1867 |
fractionalInit(); |
|
1834 | 1868 |
start(); |
1835 | 1869 |
} |
1836 | 1870 |
|
1837 | 1871 |
/// @} |
1838 | 1872 |
|
1839 | 1873 |
/// \name Primal Solution |
1840 |
/// Functions to get the primal solution, i.e. the maximum weighted |
|
1874 |
/// Functions to get the primal solution, i.e. the maximum weighted |
|
1841 | 1875 |
/// matching.\n |
1842 | 1876 |
/// Either \ref run() or \ref start() function should be called before |
1843 | 1877 |
/// using them. |
1844 | 1878 |
|
1845 | 1879 |
/// @{ |
1846 | 1880 |
|
... | ... |
@@ -1853,13 +1887,13 @@ |
1853 | 1887 |
Value sum = 0; |
1854 | 1888 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
1855 | 1889 |
if ((*_matching)[n] != INVALID) { |
1856 | 1890 |
sum += _weight[(*_matching)[n]]; |
1857 | 1891 |
} |
1858 | 1892 |
} |
1859 |
return sum / |
|
1893 |
return sum / 2; |
|
1860 | 1894 |
} |
1861 | 1895 |
|
1862 | 1896 |
/// \brief Return the size (cardinality) of the matching. |
1863 | 1897 |
/// |
1864 | 1898 |
/// This function returns the size (cardinality) of the found matching. |
1865 | 1899 |
/// |
... | ... |
@@ -1873,24 +1907,24 @@ |
1873 | 1907 |
} |
1874 | 1908 |
return num /= 2; |
1875 | 1909 |
} |
1876 | 1910 |
|
1877 | 1911 |
/// \brief Return \c true if the given edge is in the matching. |
1878 | 1912 |
/// |
1879 |
/// This function returns \c true if the given edge is in the found |
|
1913 |
/// This function returns \c true if the given edge is in the found |
|
1880 | 1914 |
/// matching. |
1881 | 1915 |
/// |
1882 | 1916 |
/// \pre Either run() or start() must be called before using this function. |
1883 | 1917 |
bool matching(const Edge& edge) const { |
1884 | 1918 |
return edge == (*_matching)[_graph.u(edge)]; |
1885 | 1919 |
} |
1886 | 1920 |
|
1887 | 1921 |
/// \brief Return the matching arc (or edge) incident to the given node. |
1888 | 1922 |
/// |
1889 | 1923 |
/// This function returns the matching arc (or edge) incident to the |
1890 |
/// given node in the found matching or \c INVALID if the node is |
|
1924 |
/// given node in the found matching or \c INVALID if the node is |
|
1891 | 1925 |
/// not covered by the matching. |
1892 | 1926 |
/// |
1893 | 1927 |
/// \pre Either run() or start() must be called before using this function. |
1894 | 1928 |
Arc matching(const Node& node) const { |
1895 | 1929 |
return (*_matching)[node]; |
1896 | 1930 |
} |
... | ... |
@@ -1902,13 +1936,13 @@ |
1902 | 1936 |
const MatchingMap& matchingMap() const { |
1903 | 1937 |
return *_matching; |
1904 | 1938 |
} |
1905 | 1939 |
|
1906 | 1940 |
/// \brief Return the mate of the given node. |
1907 | 1941 |
/// |
1908 |
/// This function returns the mate of the given node in the found |
|
1942 |
/// This function returns the mate of the given node in the found |
|
1909 | 1943 |
/// matching or \c INVALID if the node is not covered by the matching. |
1910 | 1944 |
/// |
1911 | 1945 |
/// \pre Either run() or start() must be called before using this function. |
1912 | 1946 |
Node mate(const Node& node) const { |
1913 | 1947 |
return (*_matching)[node] != INVALID ? |
1914 | 1948 |
_graph.target((*_matching)[node]) : INVALID; |
... | ... |
@@ -1922,14 +1956,14 @@ |
1922 | 1956 |
/// using them. |
1923 | 1957 |
|
1924 | 1958 |
/// @{ |
1925 | 1959 |
|
1926 | 1960 |
/// \brief Return the value of the dual solution. |
1927 | 1961 |
/// |
1928 |
/// This function returns the value of the dual solution. |
|
1929 |
/// It should be equal to the primal value scaled by \ref dualScale |
|
1962 |
/// This function returns the value of the dual solution. |
|
1963 |
/// It should be equal to the primal value scaled by \ref dualScale |
|
1930 | 1964 |
/// "dual scale". |
1931 | 1965 |
/// |
1932 | 1966 |
/// \pre Either run() or start() must be called before using this function. |
1933 | 1967 |
Value dualValue() const { |
1934 | 1968 |
Value sum = 0; |
1935 | 1969 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
... | ... |
@@ -1978,25 +2012,25 @@ |
1978 | 2012 |
Value blossomValue(int k) const { |
1979 | 2013 |
return _blossom_potential[k].value; |
1980 | 2014 |
} |
1981 | 2015 |
|
1982 | 2016 |
/// \brief Iterator for obtaining the nodes of a blossom. |
1983 | 2017 |
/// |
1984 |
/// This class provides an iterator for obtaining the nodes of the |
|
2018 |
/// This class provides an iterator for obtaining the nodes of the |
|
1985 | 2019 |
/// given blossom. It lists a subset of the nodes. |
1986 |
/// Before using this iterator, you must allocate a |
|
2020 |
/// Before using this iterator, you must allocate a |
|
1987 | 2021 |
/// MaxWeightedMatching class and execute it. |
1988 | 2022 |
class BlossomIt { |
1989 | 2023 |
public: |
1990 | 2024 |
|
1991 | 2025 |
/// \brief Constructor. |
1992 | 2026 |
/// |
1993 | 2027 |
/// Constructor to get the nodes of the given variable. |
1994 | 2028 |
/// |
1995 |
/// \pre Either \ref MaxWeightedMatching::run() "algorithm.run()" or |
|
1996 |
/// \ref MaxWeightedMatching::start() "algorithm.start()" must be |
|
2029 |
/// \pre Either \ref MaxWeightedMatching::run() "algorithm.run()" or |
|
2030 |
/// \ref MaxWeightedMatching::start() "algorithm.start()" must be |
|
1997 | 2031 |
/// called before initializing this iterator. |
1998 | 2032 |
BlossomIt(const MaxWeightedMatching& algorithm, int variable) |
1999 | 2033 |
: _algorithm(&algorithm) |
2000 | 2034 |
{ |
2001 | 2035 |
_index = _algorithm->_blossom_potential[variable].begin; |
2002 | 2036 |
_last = _algorithm->_blossom_potential[variable].end; |
... | ... |
@@ -2043,14 +2077,14 @@ |
2043 | 2077 |
/// |
2044 | 2078 |
/// This class provides an efficient implementation of Edmond's |
2045 | 2079 |
/// maximum weighted perfect matching algorithm. The implementation |
2046 | 2080 |
/// is based on extensive use of priority queues and provides |
2047 | 2081 |
/// \f$O(nm\log n)\f$ time complexity. |
2048 | 2082 |
/// |
2049 |
/// The maximum weighted perfect matching problem is to find a subset of |
|
2050 |
/// the edges in an undirected graph with maximum overall weight for which |
|
2083 |
/// The maximum weighted perfect matching problem is to find a subset of |
|
2084 |
/// the edges in an undirected graph with maximum overall weight for which |
|
2051 | 2085 |
/// each node has exactly one incident edge. |
2052 | 2086 |
/// It can be formulated with the following linear program. |
2053 | 2087 |
/// \f[ \sum_{e \in \delta(u)}x_e = 1 \quad \forall u\in V\f] |
2054 | 2088 |
/** \f[ \sum_{e \in \gamma(B)}x_e \le \frac{\vert B \vert - 1}{2} |
2055 | 2089 |
\quad \forall B\in\mathcal{O}\f] */ |
2056 | 2090 |
/// \f[x_e \ge 0\quad \forall e\in E\f] |
... | ... |
@@ -2067,22 +2101,22 @@ |
2067 | 2101 |
/** \f[ y_u + y_v + \sum_{B \in \mathcal{O}, uv \in \gamma(B)}z_B \ge |
2068 | 2102 |
w_{uv} \quad \forall uv\in E\f] */ |
2069 | 2103 |
/// \f[z_B \ge 0 \quad \forall B \in \mathcal{O}\f] |
2070 | 2104 |
/** \f[\min \sum_{u \in V}y_u + \sum_{B \in \mathcal{O}} |
2071 | 2105 |
\frac{\vert B \vert - 1}{2}z_B\f] */ |
2072 | 2106 |
/// |
2073 |
/// The algorithm can be executed with the run() function. |
|
2107 |
/// The algorithm can be executed with the run() function. |
|
2074 | 2108 |
/// After it the matching (the primal solution) and the dual solution |
2075 |
/// can be obtained using the query functions and the |
|
2076 |
/// \ref MaxWeightedPerfectMatching::BlossomIt "BlossomIt" nested class, |
|
2077 |
/// |
|
2109 |
/// can be obtained using the query functions and the |
|
2110 |
/// \ref MaxWeightedPerfectMatching::BlossomIt "BlossomIt" nested class, |
|
2111 |
/// which is able to iterate on the nodes of a blossom. |
|
2078 | 2112 |
/// If the value type is integer, then the dual solution is multiplied |
2079 | 2113 |
/// by \ref MaxWeightedMatching::dualScale "4". |
2080 | 2114 |
/// |
2081 | 2115 |
/// \tparam GR The undirected graph type the algorithm runs on. |
2082 |
/// \tparam WM The type edge weight map. The default type is |
|
2116 |
/// \tparam WM The type edge weight map. The default type is |
|
2083 | 2117 |
/// \ref concepts::Graph::EdgeMap "GR::EdgeMap<int>". |
2084 | 2118 |
#ifdef DOXYGEN |
2085 | 2119 |
template <typename GR, typename WM> |
2086 | 2120 |
#else |
2087 | 2121 |
template <typename GR, |
2088 | 2122 |
typename WM = typename GR::template EdgeMap<int> > |
... | ... |
@@ -2187,12 +2221,17 @@ |
2187 | 2221 |
BinHeap<Value, IntEdgeMap> *_delta3; |
2188 | 2222 |
|
2189 | 2223 |
IntIntMap *_delta4_index; |
2190 | 2224 |
BinHeap<Value, IntIntMap> *_delta4; |
2191 | 2225 |
|
2192 | 2226 |
Value _delta_sum; |
2227 |
int _unmatched; |
|
2228 |
|
|
2229 |
typedef MaxWeightedPerfectFractionalMatching<Graph, WeightMap> |
|
2230 |
FractionalMatching; |
|
2231 |
FractionalMatching *_fractional; |
|
2193 | 2232 |
|
2194 | 2233 |
void createStructures() { |
2195 | 2234 |
_node_num = countNodes(_graph); |
2196 | 2235 |
_blossom_num = _node_num * 3 / 2; |
2197 | 2236 |
|
2198 | 2237 |
if (!_matching) { |
... | ... |
@@ -2230,15 +2269,12 @@ |
2230 | 2269 |
_delta4_index = new IntIntMap(_blossom_num); |
2231 | 2270 |
_delta4 = new BinHeap<Value, IntIntMap>(*_delta4_index); |
2232 | 2271 |
} |
2233 | 2272 |
} |
2234 | 2273 |
|
2235 | 2274 |
void destroyStructures() { |
2236 |
_node_num = countNodes(_graph); |
|
2237 |
_blossom_num = _node_num * 3 / 2; |
|
2238 |
|
|
2239 | 2275 |
if (_matching) { |
2240 | 2276 |
delete _matching; |
2241 | 2277 |
} |
2242 | 2278 |
if (_node_potential) { |
2243 | 2279 |
delete _node_potential; |
2244 | 2280 |
} |
... | ... |
@@ -2905,16 +2941,22 @@ |
2905 | 2941 |
_tree_set_index(0), _tree_set(0), |
2906 | 2942 |
|
2907 | 2943 |
_delta2_index(0), _delta2(0), |
2908 | 2944 |
_delta3_index(0), _delta3(0), |
2909 | 2945 |
_delta4_index(0), _delta4(0), |
2910 | 2946 |
|
2911 |
_delta_sum() |
|
2947 |
_delta_sum(), _unmatched(0), |
|
2948 |
|
|
2949 |
_fractional(0) |
|
2950 |
{} |
|
2912 | 2951 |
|
2913 | 2952 |
~MaxWeightedPerfectMatching() { |
2914 | 2953 |
destroyStructures(); |
2954 |
if (_fractional) { |
|
2955 |
delete _fractional; |
|
2956 |
} |
|
2915 | 2957 |
} |
2916 | 2958 |
|
2917 | 2959 |
/// \name Execution Control |
2918 | 2960 |
/// The simplest way to execute the algorithm is to use the |
2919 | 2961 |
/// \ref run() member function. |
2920 | 2962 |
|
... | ... |
@@ -2934,12 +2976,14 @@ |
2934 | 2976 |
} |
2935 | 2977 |
for (int i = 0; i < _blossom_num; ++i) { |
2936 | 2978 |
(*_delta2_index)[i] = _delta2->PRE_HEAP; |
2937 | 2979 |
(*_delta4_index)[i] = _delta4->PRE_HEAP; |
2938 | 2980 |
} |
2939 | 2981 |
|
2982 |
_unmatched = _node_num; |
|
2983 |
|
|
2940 | 2984 |
int index = 0; |
2941 | 2985 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
2942 | 2986 |
Value max = - std::numeric_limits<Value>::max(); |
2943 | 2987 |
for (OutArcIt e(_graph, n); e != INVALID; ++e) { |
2944 | 2988 |
if (_graph.target(e) == n) continue; |
2945 | 2989 |
if ((dualScale * _weight[e]) / 2 > max) { |
... | ... |
@@ -2967,35 +3011,169 @@ |
2967 | 3011 |
_delta3->push(e, ((*_node_data)[si].pot + (*_node_data)[ti].pot - |
2968 | 3012 |
dualScale * _weight[e]) / 2); |
2969 | 3013 |
} |
2970 | 3014 |
} |
2971 | 3015 |
} |
2972 | 3016 |
|
3017 |
/// \brief Initialize the algorithm with fractional matching |
|
3018 |
/// |
|
3019 |
/// This function initializes the algorithm with a fractional |
|
3020 |
/// matching. This initialization is also called jumpstart heuristic. |
|
3021 |
void fractionalInit() { |
|
3022 |
createStructures(); |
|
3023 |
|
|
3024 |
if (_fractional == 0) { |
|
3025 |
_fractional = new FractionalMatching(_graph, _weight, false); |
|
3026 |
} |
|
3027 |
if (!_fractional->run()) { |
|
3028 |
_unmatched = -1; |
|
3029 |
return; |
|
3030 |
} |
|
3031 |
|
|
3032 |
for (ArcIt e(_graph); e != INVALID; ++e) { |
|
3033 |
(*_node_heap_index)[e] = BinHeap<Value, IntArcMap>::PRE_HEAP; |
|
3034 |
} |
|
3035 |
for (EdgeIt e(_graph); e != INVALID; ++e) { |
|
3036 |
(*_delta3_index)[e] = _delta3->PRE_HEAP; |
|
3037 |
} |
|
3038 |
for (int i = 0; i < _blossom_num; ++i) { |
|
3039 |
(*_delta2_index)[i] = _delta2->PRE_HEAP; |
|
3040 |
(*_delta4_index)[i] = _delta4->PRE_HEAP; |
|
3041 |
} |
|
3042 |
|
|
3043 |
_unmatched = 0; |
|
3044 |
|
|
3045 |
int index = 0; |
|
3046 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
3047 |
Value pot = _fractional->nodeValue(n); |
|
3048 |
(*_node_index)[n] = index; |
|
3049 |
(*_node_data)[index].pot = pot; |
|
3050 |
int blossom = |
|
3051 |
_blossom_set->insert(n, std::numeric_limits<Value>::max()); |
|
3052 |
|
|
3053 |
(*_blossom_data)[blossom].status = MATCHED; |
|
3054 |
(*_blossom_data)[blossom].pred = INVALID; |
|
3055 |
(*_blossom_data)[blossom].next = _fractional->matching(n); |
|
3056 |
(*_blossom_data)[blossom].pot = 0; |
|
3057 |
(*_blossom_data)[blossom].offset = 0; |
|
3058 |
++index; |
|
3059 |
} |
|
3060 |
|
|
3061 |
typename Graph::template NodeMap<bool> processed(_graph, false); |
|
3062 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
3063 |
if (processed[n]) continue; |
|
3064 |
processed[n] = true; |
|
3065 |
if (_fractional->matching(n) == INVALID) continue; |
|
3066 |
int num = 1; |
|
3067 |
Node v = _graph.target(_fractional->matching(n)); |
|
3068 |
while (n != v) { |
|
3069 |
processed[v] = true; |
|
3070 |
v = _graph.target(_fractional->matching(v)); |
|
3071 |
++num; |
|
3072 |
} |
|
3073 |
|
|
3074 |
if (num % 2 == 1) { |
|
3075 |
std::vector<int> subblossoms(num); |
|
3076 |
|
|
3077 |
subblossoms[--num] = _blossom_set->find(n); |
|
3078 |
v = _graph.target(_fractional->matching(n)); |
|
3079 |
while (n != v) { |
|
3080 |
subblossoms[--num] = _blossom_set->find(v); |
|
3081 |
v = _graph.target(_fractional->matching(v)); |
|
3082 |
} |
|
3083 |
|
|
3084 |
int surface = |
|
3085 |
_blossom_set->join(subblossoms.begin(), subblossoms.end()); |
|
3086 |
(*_blossom_data)[surface].status = EVEN; |
|
3087 |
(*_blossom_data)[surface].pred = INVALID; |
|
3088 |
(*_blossom_data)[surface].next = INVALID; |
|
3089 |
(*_blossom_data)[surface].pot = 0; |
|
3090 |
(*_blossom_data)[surface].offset = 0; |
|
3091 |
|
|
3092 |
_tree_set->insert(surface); |
|
3093 |
++_unmatched; |
|
3094 |
} |
|
3095 |
} |
|
3096 |
|
|
3097 |
for (EdgeIt e(_graph); e != INVALID; ++e) { |
|
3098 |
int si = (*_node_index)[_graph.u(e)]; |
|
3099 |
int sb = _blossom_set->find(_graph.u(e)); |
|
3100 |
int ti = (*_node_index)[_graph.v(e)]; |
|
3101 |
int tb = _blossom_set->find(_graph.v(e)); |
|
3102 |
if ((*_blossom_data)[sb].status == EVEN && |
|
3103 |
(*_blossom_data)[tb].status == EVEN && sb != tb) { |
|
3104 |
_delta3->push(e, ((*_node_data)[si].pot + (*_node_data)[ti].pot - |
|
3105 |
dualScale * _weight[e]) / 2); |
|
3106 |
} |
|
3107 |
} |
|
3108 |
|
|
3109 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
|
3110 |
int nb = _blossom_set->find(n); |
|
3111 |
if ((*_blossom_data)[nb].status != MATCHED) continue; |
|
3112 |
int ni = (*_node_index)[n]; |
|
3113 |
|
|
3114 |
for (OutArcIt e(_graph, n); e != INVALID; ++e) { |
|
3115 |
Node v = _graph.target(e); |
|
3116 |
int vb = _blossom_set->find(v); |
|
3117 |
int vi = (*_node_index)[v]; |
|
3118 |
|
|
3119 |
Value rw = (*_node_data)[ni].pot + (*_node_data)[vi].pot - |
|
3120 |
dualScale * _weight[e]; |
|
3121 |
|
|
3122 |
if ((*_blossom_data)[vb].status == EVEN) { |
|
3123 |
|
|
3124 |
int vt = _tree_set->find(vb); |
|
3125 |
|
|
3126 |
typename std::map<int, Arc>::iterator it = |
|
3127 |
(*_node_data)[ni].heap_index.find(vt); |
|
3128 |
|
|
3129 |
if (it != (*_node_data)[ni].heap_index.end()) { |
|
3130 |
if ((*_node_data)[ni].heap[it->second] > rw) { |
|
3131 |
(*_node_data)[ni].heap.replace(it->second, e); |
|
3132 |
(*_node_data)[ni].heap.decrease(e, rw); |
|
3133 |
it->second = e; |
|
3134 |
} |
|
3135 |
} else { |
|
3136 |
(*_node_data)[ni].heap.push(e, rw); |
|
3137 |
(*_node_data)[ni].heap_index.insert(std::make_pair(vt, e)); |
|
3138 |
} |
|
3139 |
} |
|
3140 |
} |
|
3141 |
|
|
3142 |
if (!(*_node_data)[ni].heap.empty()) { |
|
3143 |
_blossom_set->decrease(n, (*_node_data)[ni].heap.prio()); |
|
3144 |
_delta2->push(nb, _blossom_set->classPrio(nb)); |
|
3145 |
} |
|
3146 |
} |
|
3147 |
} |
|
3148 |
|
|
2973 | 3149 |
/// \brief Start the algorithm |
2974 | 3150 |
/// |
2975 | 3151 |
/// This function starts the algorithm. |
2976 | 3152 |
/// |
2977 |
/// \pre \ref init() must be called before |
|
3153 |
/// \pre \ref init() or \ref fractionalInit() must be called before |
|
3154 |
/// using this function. |
|
2978 | 3155 |
bool start() { |
2979 | 3156 |
enum OpType { |
2980 | 3157 |
D2, D3, D4 |
2981 | 3158 |
}; |
2982 | 3159 |
|
2983 |
int unmatched = _node_num; |
|
2984 |
while (unmatched > 0) { |
|
3160 |
if (_unmatched == -1) return false; |
|
3161 |
|
|
3162 |
while (_unmatched > 0) { |
|
2985 | 3163 |
Value d2 = !_delta2->empty() ? |
2986 | 3164 |
_delta2->prio() : std::numeric_limits<Value>::max(); |
2987 | 3165 |
|
2988 | 3166 |
Value d3 = !_delta3->empty() ? |
2989 | 3167 |
_delta3->prio() : std::numeric_limits<Value>::max(); |
2990 | 3168 |
|
2991 | 3169 |
Value d4 = !_delta4->empty() ? |
2992 | 3170 |
_delta4->prio() : std::numeric_limits<Value>::max(); |
2993 | 3171 |
|
2994 |
_delta_sum = d2; OpType ot = D2; |
|
2995 |
if (d3 < _delta_sum) { _delta_sum = d3; ot = D3; } |
|
3172 |
_delta_sum = d3; OpType ot = D3; |
|
3173 |
if (d2 < _delta_sum) { _delta_sum = d2; ot = D2; } |
|
2996 | 3174 |
if (d4 < _delta_sum) { _delta_sum = d4; ot = D4; } |
2997 | 3175 |
|
2998 | 3176 |
if (_delta_sum == std::numeric_limits<Value>::max()) { |
2999 | 3177 |
return false; |
3000 | 3178 |
} |
3001 | 3179 |
|
... | ... |
@@ -3022,13 +3200,13 @@ |
3022 | 3200 |
int right_tree = _tree_set->find(right_blossom); |
3023 | 3201 |
|
3024 | 3202 |
if (left_tree == right_tree) { |
3025 | 3203 |
shrinkOnEdge(e, left_tree); |
3026 | 3204 |
} else { |
3027 | 3205 |
augmentOnEdge(e); |
3028 |
|
|
3206 |
_unmatched -= 2; |
|
3029 | 3207 |
} |
3030 | 3208 |
} |
3031 | 3209 |
} break; |
3032 | 3210 |
case D4: |
3033 | 3211 |
splitBlossom(_delta4->top()); |
3034 | 3212 |
break; |
... | ... |
@@ -3041,24 +3219,24 @@ |
3041 | 3219 |
/// \brief Run the algorithm. |
3042 | 3220 |
/// |
3043 | 3221 |
/// This method runs the \c %MaxWeightedPerfectMatching algorithm. |
3044 | 3222 |
/// |
3045 | 3223 |
/// \note mwpm.run() is just a shortcut of the following code. |
3046 | 3224 |
/// \code |
3047 |
/// mwpm. |
|
3225 |
/// mwpm.fractionalInit(); |
|
3048 | 3226 |
/// mwpm.start(); |
3049 | 3227 |
/// \endcode |
3050 | 3228 |
bool run() { |
3051 |
|
|
3229 |
fractionalInit(); |
|
3052 | 3230 |
return start(); |
3053 | 3231 |
} |
3054 | 3232 |
|
3055 | 3233 |
/// @} |
3056 | 3234 |
|
3057 | 3235 |
/// \name Primal Solution |
3058 |
/// Functions to get the primal solution, i.e. the maximum weighted |
|
3236 |
/// Functions to get the primal solution, i.e. the maximum weighted |
|
3059 | 3237 |
/// perfect matching.\n |
3060 | 3238 |
/// Either \ref run() or \ref start() function should be called before |
3061 | 3239 |
/// using them. |
3062 | 3240 |
|
3063 | 3241 |
/// @{ |
3064 | 3242 |
|
... | ... |
@@ -3071,29 +3249,29 @@ |
3071 | 3249 |
Value sum = 0; |
3072 | 3250 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
3073 | 3251 |
if ((*_matching)[n] != INVALID) { |
3074 | 3252 |
sum += _weight[(*_matching)[n]]; |
3075 | 3253 |
} |
3076 | 3254 |
} |
3077 |
return sum / |
|
3255 |
return sum / 2; |
|
3078 | 3256 |
} |
3079 | 3257 |
|
3080 | 3258 |
/// \brief Return \c true if the given edge is in the matching. |
3081 | 3259 |
/// |
3082 |
/// This function returns \c true if the given edge is in the found |
|
3260 |
/// This function returns \c true if the given edge is in the found |
|
3083 | 3261 |
/// matching. |
3084 | 3262 |
/// |
3085 | 3263 |
/// \pre Either run() or start() must be called before using this function. |
3086 | 3264 |
bool matching(const Edge& edge) const { |
3087 | 3265 |
return static_cast<const Edge&>((*_matching)[_graph.u(edge)]) == edge; |
3088 | 3266 |
} |
3089 | 3267 |
|
3090 | 3268 |
/// \brief Return the matching arc (or edge) incident to the given node. |
3091 | 3269 |
/// |
3092 | 3270 |
/// This function returns the matching arc (or edge) incident to the |
3093 |
/// given node in the found matching or \c INVALID if the node is |
|
3271 |
/// given node in the found matching or \c INVALID if the node is |
|
3094 | 3272 |
/// not covered by the matching. |
3095 | 3273 |
/// |
3096 | 3274 |
/// \pre Either run() or start() must be called before using this function. |
3097 | 3275 |
Arc matching(const Node& node) const { |
3098 | 3276 |
return (*_matching)[node]; |
3099 | 3277 |
} |
... | ... |
@@ -3105,13 +3283,13 @@ |
3105 | 3283 |
const MatchingMap& matchingMap() const { |
3106 | 3284 |
return *_matching; |
3107 | 3285 |
} |
3108 | 3286 |
|
3109 | 3287 |
/// \brief Return the mate of the given node. |
3110 | 3288 |
/// |
3111 |
/// This function returns the mate of the given node in the found |
|
3289 |
/// This function returns the mate of the given node in the found |
|
3112 | 3290 |
/// matching or \c INVALID if the node is not covered by the matching. |
3113 | 3291 |
/// |
3114 | 3292 |
/// \pre Either run() or start() must be called before using this function. |
3115 | 3293 |
Node mate(const Node& node) const { |
3116 | 3294 |
return _graph.target((*_matching)[node]); |
3117 | 3295 |
} |
... | ... |
@@ -3124,14 +3302,14 @@ |
3124 | 3302 |
/// using them. |
3125 | 3303 |
|
3126 | 3304 |
/// @{ |
3127 | 3305 |
|
3128 | 3306 |
/// \brief Return the value of the dual solution. |
3129 | 3307 |
/// |
3130 |
/// This function returns the value of the dual solution. |
|
3131 |
/// It should be equal to the primal value scaled by \ref dualScale |
|
3308 |
/// This function returns the value of the dual solution. |
|
3309 |
/// It should be equal to the primal value scaled by \ref dualScale |
|
3132 | 3310 |
/// "dual scale". |
3133 | 3311 |
/// |
3134 | 3312 |
/// \pre Either run() or start() must be called before using this function. |
3135 | 3313 |
Value dualValue() const { |
3136 | 3314 |
Value sum = 0; |
3137 | 3315 |
for (NodeIt n(_graph); n != INVALID; ++n) { |
... | ... |
@@ -3180,25 +3358,25 @@ |
3180 | 3358 |
Value blossomValue(int k) const { |
3181 | 3359 |
return _blossom_potential[k].value; |
3182 | 3360 |
} |
3183 | 3361 |
|
3184 | 3362 |
/// \brief Iterator for obtaining the nodes of a blossom. |
3185 | 3363 |
/// |
3186 |
/// This class provides an iterator for obtaining the nodes of the |
|
3364 |
/// This class provides an iterator for obtaining the nodes of the |
|
3187 | 3365 |
/// given blossom. It lists a subset of the nodes. |
3188 |
/// Before using this iterator, you must allocate a |
|
3366 |
/// Before using this iterator, you must allocate a |
|
3189 | 3367 |
/// MaxWeightedPerfectMatching class and execute it. |
3190 | 3368 |
class BlossomIt { |
3191 | 3369 |
public: |
3192 | 3370 |
|
3193 | 3371 |
/// \brief Constructor. |
3194 | 3372 |
/// |
3195 | 3373 |
/// Constructor to get the nodes of the given variable. |
3196 | 3374 |
/// |
3197 |
/// \pre Either \ref MaxWeightedPerfectMatching::run() "algorithm.run()" |
|
3198 |
/// or \ref MaxWeightedPerfectMatching::start() "algorithm.start()" |
|
3375 |
/// \pre Either \ref MaxWeightedPerfectMatching::run() "algorithm.run()" |
|
3376 |
/// or \ref MaxWeightedPerfectMatching::start() "algorithm.start()" |
|
3199 | 3377 |
/// must be called before initializing this iterator. |
3200 | 3378 |
BlossomIt(const MaxWeightedPerfectMatching& algorithm, int variable) |
3201 | 3379 |
: _algorithm(&algorithm) |
3202 | 3380 |
{ |
3203 | 3381 |
_index = _algorithm->_blossom_potential[variable].begin; |
3204 | 3382 |
_last = _algorithm->_blossom_potential[variable].end; |
... | ... |
@@ -3238,7 +3416,7 @@ |
3238 | 3416 |
/// @} |
3239 | 3417 |
|
3240 | 3418 |
}; |
3241 | 3419 |
|
3242 | 3420 |
} //END OF NAMESPACE LEMON |
3243 | 3421 |
|
3244 |
#endif // |
|
3422 |
#endif //LEMON_MATCHING_H |
... | ... |
@@ -20,12 +20,13 @@ |
20 | 20 |
test/digraph_test \ |
21 | 21 |
test/dijkstra_test \ |
22 | 22 |
test/dim_test \ |
23 | 23 |
test/edge_set_test \ |
24 | 24 |
test/error_test \ |
25 | 25 |
test/euler_test \ |
26 |
test/fractional_matching_test \ |
|
26 | 27 |
test/gomory_hu_test \ |
27 | 28 |
test/graph_copy_test \ |
28 | 29 |
test/graph_test \ |
29 | 30 |
test/graph_utils_test \ |
30 | 31 |
test/hao_orlin_test \ |
31 | 32 |
test/heap_test \ |
... | ... |
@@ -68,12 +69,13 @@ |
68 | 69 |
test_digraph_test_SOURCES = test/digraph_test.cc |
69 | 70 |
test_dijkstra_test_SOURCES = test/dijkstra_test.cc |
70 | 71 |
test_dim_test_SOURCES = test/dim_test.cc |
71 | 72 |
test_edge_set_test_SOURCES = test/edge_set_test.cc |
72 | 73 |
test_error_test_SOURCES = test/error_test.cc |
73 | 74 |
test_euler_test_SOURCES = test/euler_test.cc |
75 |
test_fractional_matching_test_SOURCES = test/fractional_matching_test.cc |
|
74 | 76 |
test_gomory_hu_test_SOURCES = test/gomory_hu_test.cc |
75 | 77 |
test_graph_copy_test_SOURCES = test/graph_copy_test.cc |
76 | 78 |
test_graph_test_SOURCES = test/graph_test.cc |
77 | 79 |
test_graph_utils_test_SOURCES = test/graph_utils_test.cc |
78 | 80 |
test_heap_test_SOURCES = test/heap_test.cc |
79 | 81 |
test_kruskal_test_SOURCES = test/kruskal_test.cc |
... | ... |
@@ -398,27 +398,51 @@ |
398 | 398 |
SmartGraph::EdgeMap<int> weight(graph); |
399 | 399 |
|
400 | 400 |
istringstream lgfs(lgf[i]); |
401 | 401 |
graphReader(graph, lgfs). |
402 | 402 |
edgeMap("weight", weight).run(); |
403 | 403 |
|
404 |
MaxMatching<SmartGraph> mm(graph); |
|
405 |
mm.run(); |
|
406 |
|
|
404 |
bool perfect; |
|
405 |
{ |
|
406 |
MaxMatching<SmartGraph> mm(graph); |
|
407 |
mm.run(); |
|
408 |
checkMatching(graph, mm); |
|
409 |
perfect = 2 * mm.matchingSize() == countNodes(graph); |
|
410 |
} |
|
407 | 411 |
|
408 |
MaxWeightedMatching<SmartGraph> mwm(graph, weight); |
|
409 |
mwm.run(); |
|
410 |
|
|
412 |
{ |
|
413 |
MaxWeightedMatching<SmartGraph> mwm(graph, weight); |
|
414 |
mwm.run(); |
|
415 |
checkWeightedMatching(graph, weight, mwm); |
|
416 |
} |
|
411 | 417 |
|
412 |
MaxWeightedPerfectMatching<SmartGraph> mwpm(graph, weight); |
|
413 |
bool perfect = mwpm.run(); |
|
418 |
{ |
|
419 |
MaxWeightedMatching<SmartGraph> mwm(graph, weight); |
|
420 |
mwm.init(); |
|
421 |
mwm.start(); |
|
422 |
checkWeightedMatching(graph, weight, mwm); |
|
423 |
} |
|
414 | 424 |
|
415 |
check(perfect == (mm.matchingSize() * 2 == countNodes(graph)), |
|
416 |
"Perfect matching found"); |
|
425 |
{ |
|
426 |
MaxWeightedPerfectMatching<SmartGraph> mwpm(graph, weight); |
|
427 |
bool result = mwpm.run(); |
|
428 |
|
|
429 |
check(result == perfect, "Perfect matching found"); |
|
430 |
if (perfect) { |
|
431 |
checkWeightedPerfectMatching(graph, weight, mwpm); |
|
432 |
} |
|
433 |
} |
|
417 | 434 |
|
418 |
if (perfect) { |
|
419 |
checkWeightedPerfectMatching(graph, weight, mwpm); |
|
435 |
{ |
|
436 |
MaxWeightedPerfectMatching<SmartGraph> mwpm(graph, weight); |
|
437 |
mwpm.init(); |
|
438 |
bool result = mwpm.start(); |
|
439 |
|
|
440 |
check(result == perfect, "Perfect matching found"); |
|
441 |
if (perfect) { |
|
442 |
checkWeightedPerfectMatching(graph, weight, mwpm); |
|
443 |
} |
|
420 | 444 |
} |
421 | 445 |
} |
422 | 446 |
|
423 | 447 |
return 0; |
424 | 448 |
} |
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