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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) 2003-2008
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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_MAX_MATCHING_H
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#define LEMON_MAX_MATCHING_H
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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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#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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///\ingroup matching
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///\file
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///\brief Maximum matching algorithms in graph.
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namespace lemon {
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///\ingroup matching
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///
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///\brief Edmonds' alternating forest maximum matching algorithm.
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///
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///This class provides Edmonds' alternating forest matching
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///algorithm. The starting matching (if any) can be passed to the
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///algorithm using some of init functions.
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///
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///The dual side of a matching is a map of the nodes to
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///MaxMatching::DecompType, having values \c D, \c A and \c C
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///showing the Gallai-Edmonds decomposition of the digraph. The nodes
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///in \c D induce a digraph with factor-critical components, the nodes
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///in \c A form the barrier, and the nodes in \c C induce a digraph
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///having a perfect matching. This decomposition can be attained by
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///calling \c decomposition() after running the algorithm.
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///
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///\param Digraph The graph type the algorithm runs on.
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template <typename Graph>
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class MaxMatching {
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protected:
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TEMPLATE_GRAPH_TYPEDEFS(Graph);
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typedef typename Graph::template NodeMap<int> UFECrossRef;
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typedef UnionFindEnum<UFECrossRef> UFE;
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typedef std::vector<Node> NV;
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typedef typename Graph::template NodeMap<int> EFECrossRef;
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typedef ExtendFindEnum<EFECrossRef> EFE;
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public:
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///\brief Indicates the Gallai-Edmonds decomposition of the digraph.
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///
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///Indicates the Gallai-Edmonds decomposition of the digraph, which
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///shows an upper bound on the size of a maximum matching. The
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///nodes with DecompType \c D induce a digraph with factor-critical
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///components, the nodes in \c A form the canonical barrier, and the
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///nodes in \c C induce a digraph having a perfect matching.
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enum DecompType {
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D=0,
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A=1,
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C=2
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};
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protected:
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static const int HEUR_density=2;
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const Graph& g;
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typename Graph::template NodeMap<Node> _mate;
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typename Graph::template NodeMap<DecompType> position;
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public:
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MaxMatching(const Graph& _g)
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: g(_g), _mate(_g), position(_g) {}
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///\brief Sets the actual matching to the empty matching.
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///
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///Sets the actual matching to the empty matching.
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///
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void init() {
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for(NodeIt v(g); v!=INVALID; ++v) {
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_mate.set(v,INVALID);
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position.set(v,C);
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}
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}
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///\brief Finds a greedy matching for initial matching.
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///
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///For initial matchig it finds a maximal greedy matching.
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void greedyInit() {
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for(NodeIt v(g); v!=INVALID; ++v) {
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_mate.set(v,INVALID);
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position.set(v,C);
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}
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for(NodeIt v(g); v!=INVALID; ++v)
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if ( _mate[v]==INVALID ) {
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for( IncEdgeIt e(g,v); e!=INVALID ; ++e ) {
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Node y=g.runningNode(e);
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if ( _mate[y]==INVALID && y!=v ) {
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_mate.set(v,y);
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_mate.set(y,v);
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break;
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}
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}
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}
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}
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///\brief Initialize the matching from each nodes' mate.
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///
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///Initialize the matching from a \c Node valued \c Node map. This
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///map must be \e symmetric, i.e. if \c map[u]==v then \c
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///map[v]==u must hold, and \c uv will be an arc of the initial
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///matching.
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template <typename MateMap>
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void mateMapInit(MateMap& map) {
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for(NodeIt v(g); v!=INVALID; ++v) {
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_mate.set(v,map[v]);
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position.set(v,C);
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}
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}
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///\brief Initialize the matching from a node map with the
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///incident matching arcs.
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///
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///Initialize the matching from an \c Edge valued \c Node map. \c
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///map[v] must be an \c Edge incident to \c v. This map must have
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///the property that if \c g.oppositeNode(u,map[u])==v then \c \c
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///g.oppositeNode(v,map[v])==u holds, and now some arc joining \c
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///u to \c v will be an arc of the matching.
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template<typename MatchingMap>
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void matchingMapInit(MatchingMap& map) {
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for(NodeIt v(g); v!=INVALID; ++v) {
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position.set(v,C);
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Edge e=map[v];
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if ( e!=INVALID )
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_mate.set(v,g.oppositeNode(v,e));
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else
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_mate.set(v,INVALID);
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}
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}
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///\brief Initialize the matching from the map containing the
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///undirected matching arcs.
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///
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///Initialize the matching from a \c bool valued \c Edge map. This
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///map must have the property that there are no two incident arcs
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///\c e, \c f with \c map[e]==map[f]==true. The arcs \c e with \c
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///map[e]==true form the matching.
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template <typename MatchingMap>
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void matchingInit(MatchingMap& map) {
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for(NodeIt v(g); v!=INVALID; ++v) {
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_mate.set(v,INVALID);
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position.set(v,C);
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}
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for(EdgeIt e(g); e!=INVALID; ++e) {
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if ( map[e] ) {
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Node u=g.u(e);
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Node v=g.v(e);
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_mate.set(u,v);
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_mate.set(v,u);
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}
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}
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}
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///\brief Runs Edmonds' algorithm.
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///
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///Runs Edmonds' algorithm for sparse digraphs (number of arcs <
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///2*number of nodes), and a heuristical Edmonds' algorithm with a
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///heuristic of postponing shrinks for dense digraphs.
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void run() {
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if (countEdges(g) < HEUR_density * countNodes(g)) {
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greedyInit();
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startSparse();
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} else {
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init();
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startDense();
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}
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}
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///\brief Starts Edmonds' algorithm.
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///
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///If runs the original Edmonds' algorithm.
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void startSparse() {
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typename Graph::template NodeMap<Node> ear(g,INVALID);
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//undefined for the base nodes of the blossoms (i.e. for the
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//representative elements of UFE blossom) and for the nodes in C
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UFECrossRef blossom_base(g);
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UFE blossom(blossom_base);
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NV rep(countNodes(g));
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EFECrossRef tree_base(g);
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EFE tree(tree_base);
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//If these UFE's would be members of the class then also
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//blossom_base and tree_base should be a member.
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//We build only one tree and the other vertices uncovered by the
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//matching belong to C. (They can be considered as singleton
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//trees.) If this tree can be augmented or no more
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//grow/augmentation/shrink is possible then we return to this
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//"for" cycle.
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for(NodeIt v(g); v!=INVALID; ++v) {
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if (position[v]==C && _mate[v]==INVALID) {
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rep[blossom.insert(v)] = v;
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tree.insert(v);
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position.set(v,D);
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normShrink(v, ear, blossom, rep, tree);
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}
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}
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}
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///\brief Starts Edmonds' algorithm.
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///
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///It runs Edmonds' algorithm with a heuristic of postponing
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///shrinks, giving a faster algorithm for dense digraphs.
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void startDense() {
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typename Graph::template NodeMap<Node> ear(g,INVALID);
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//undefined for the base nodes of the blossoms (i.e. for the
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//representative elements of UFE blossom) and for the nodes in C
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UFECrossRef blossom_base(g);
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UFE blossom(blossom_base);
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NV rep(countNodes(g));
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EFECrossRef tree_base(g);
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EFE tree(tree_base);
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//If these UFE's would be members of the class then also
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//blossom_base and tree_base should be a member.
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//We build only one tree and the other vertices uncovered by the
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//matching belong to C. (They can be considered as singleton
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//trees.) If this tree can be augmented or no more
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//grow/augmentation/shrink is possible then we return to this
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//"for" cycle.
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for(NodeIt v(g); v!=INVALID; ++v) {
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if ( position[v]==C && _mate[v]==INVALID ) {
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rep[blossom.insert(v)] = v;
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tree.insert(v);
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position.set(v,D);
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lateShrink(v, ear, blossom, rep, tree);
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}
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}
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}
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///\brief Returns the size of the actual matching stored.
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///
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///Returns the size of the actual matching stored. After \ref
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///run() it returns the size of a maximum matching in the digraph.
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int size() const {
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int s=0;
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for(NodeIt v(g); v!=INVALID; ++v) {
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if ( _mate[v]!=INVALID ) {
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++s;
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}
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}
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return s/2;
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}
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///\brief Returns the mate of a node in the actual matching.
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///
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///Returns the mate of a \c node in the actual matching.
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///Returns INVALID if the \c node is not covered by the actual matching.
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Node mate(const Node& node) const {
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return _mate[node];
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}
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///\brief Returns the matching arc incident to the given node.
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///
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///Returns the matching arc of a \c node in the actual matching.
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///Returns INVALID if the \c node is not covered by the actual matching.
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Edge matchingArc(const Node& node) const {
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if (_mate[node] == INVALID) return INVALID;
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Node n = node < _mate[node] ? node : _mate[node];
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for (IncEdgeIt e(g, n); e != INVALID; ++e) {
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if (g.oppositeNode(n, e) == _mate[n]) {
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return e;
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}
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}
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return INVALID;
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}
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/// \brief Returns the class of the node in the Edmonds-Gallai
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/// decomposition.
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///
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/// Returns the class of the node in the Edmonds-Gallai
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/// decomposition.
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DecompType decomposition(const Node& n) {
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return position[n] == A;
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}
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/// \brief Returns true when the node is in the barrier.
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///
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/// Returns true when the node is in the barrier.
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bool barrier(const Node& n) {
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return position[n] == A;
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}
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///\brief Gives back the matching in a \c Node of mates.
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///
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///Writes the stored matching to a \c Node valued \c Node map. The
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///resulting map will be \e symmetric, i.e. if \c map[u]==v then \c
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///map[v]==u will hold, and now \c uv is an arc of the matching.
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template <typename MateMap>
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void mateMap(MateMap& map) const {
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for(NodeIt v(g); v!=INVALID; ++v) {
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map.set(v,_mate[v]);
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}
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}
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///\brief Gives back the matching in an \c Edge valued \c Node
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///map.
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///
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///Writes the stored matching to an \c Edge valued \c Node
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///map. \c map[v] will be an \c Edge incident to \c v. This
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///map will have the property that if \c g.oppositeNode(u,map[u])
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///== v then \c map[u]==map[v] holds, and now this arc is an arc
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///of the matching.
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template <typename MatchingMap>
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void matchingMap(MatchingMap& map) const {
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typename Graph::template NodeMap<bool> todo(g,true);
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for(NodeIt v(g); v!=INVALID; ++v) {
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if (_mate[v]!=INVALID && v < _mate[v]) {
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Node u=_mate[v];
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for(IncEdgeIt e(g,v); e!=INVALID; ++e) {
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if ( g.runningNode(e) == u ) {
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map.set(u,e);
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map.set(v,e);
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todo.set(u,false);
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todo.set(v,false);
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break;
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}
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}
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}
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}
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}
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///\brief Gives back the matching in a \c bool valued \c Edge
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///map.
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///
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///Writes the matching stored to a \c bool valued \c Arc
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///map. This map will have the property that there are no two
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///incident arcs \c e, \c f with \c map[e]==map[f]==true. The
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///arcs \c e with \c map[e]==true form the matching.
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template<typename MatchingMap>
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void matching(MatchingMap& map) const {
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for(EdgeIt e(g); e!=INVALID; ++e) map.set(e,false);
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typename Graph::template NodeMap<bool> todo(g,true);
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for(NodeIt v(g); v!=INVALID; ++v) {
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if ( todo[v] && _mate[v]!=INVALID ) {
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Node u=_mate[v];
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for(IncEdgeIt e(g,v); e!=INVALID; ++e) {
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if ( g.runningNode(e) == u ) {
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map.set(e,true);
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todo.set(u,false);
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todo.set(v,false);
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break;
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}
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}
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}
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}
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}
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394 |
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///\brief Returns the canonical decomposition of the digraph after running
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///the algorithm.
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///
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///After calling any run methods of the class, it writes the
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///Gallai-Edmonds canonical decomposition of the digraph. \c map
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///must be a node map of \ref DecompType 's.
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template <typename DecompositionMap>
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void decomposition(DecompositionMap& map) const {
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for(NodeIt v(g); v!=INVALID; ++v) map.set(v,position[v]);
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}
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///\brief Returns a barrier on the nodes.
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///
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///After calling any run methods of the class, it writes a
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409 |
///canonical barrier on the nodes. The odd component number of the
|
|
410 |
///remaining digraph minus the barrier size is a lower bound for the
|
|
411 |
///uncovered nodes in the digraph. The \c map must be a node map of
|
|
412 |
///bools.
|
|
413 |
template <typename BarrierMap>
|
|
414 |
void barrier(BarrierMap& barrier) {
|
|
415 |
for(NodeIt v(g); v!=INVALID; ++v) barrier.set(v,position[v] == A);
|
|
416 |
}
|
|
417 |
|
|
418 |
private:
|
|
419 |
|
|
420 |
|
|
421 |
void lateShrink(Node v, typename Graph::template NodeMap<Node>& ear,
|
|
422 |
UFE& blossom, NV& rep, EFE& tree) {
|
|
423 |
//We have one tree which we grow, and also shrink but only if it
|
|
424 |
//cannot be postponed. If we augment then we return to the "for"
|
|
425 |
//cycle of runEdmonds().
|
|
426 |
|
|
427 |
std::queue<Node> Q; //queue of the totally unscanned nodes
|
|
428 |
Q.push(v);
|
|
429 |
std::queue<Node> R;
|
|
430 |
//queue of the nodes which must be scanned for a possible shrink
|
|
431 |
|
|
432 |
while ( !Q.empty() ) {
|
|
433 |
Node x=Q.front();
|
|
434 |
Q.pop();
|
|
435 |
for( IncEdgeIt e(g,x); e!= INVALID; ++e ) {
|
|
436 |
Node y=g.runningNode(e);
|
|
437 |
//growOrAugment grows if y is covered by the matching and
|
|
438 |
//augments if not. In this latter case it returns 1.
|
|
439 |
if (position[y]==C &&
|
|
440 |
growOrAugment(y, x, ear, blossom, rep, tree, Q)) return;
|
|
441 |
}
|
|
442 |
R.push(x);
|
|
443 |
}
|
|
444 |
|
|
445 |
while ( !R.empty() ) {
|
|
446 |
Node x=R.front();
|
|
447 |
R.pop();
|
|
448 |
|
|
449 |
for( IncEdgeIt e(g,x); e!=INVALID ; ++e ) {
|
|
450 |
Node y=g.runningNode(e);
|
|
451 |
|
|
452 |
if ( position[y] == D && blossom.find(x) != blossom.find(y) )
|
|
453 |
//Recall that we have only one tree.
|
|
454 |
shrink( x, y, ear, blossom, rep, tree, Q);
|
|
455 |
|
|
456 |
while ( !Q.empty() ) {
|
|
457 |
Node z=Q.front();
|
|
458 |
Q.pop();
|
|
459 |
for( IncEdgeIt f(g,z); f!= INVALID; ++f ) {
|
|
460 |
Node w=g.runningNode(f);
|
|
461 |
//growOrAugment grows if y is covered by the matching and
|
|
462 |
//augments if not. In this latter case it returns 1.
|
|
463 |
if (position[w]==C &&
|
|
464 |
growOrAugment(w, z, ear, blossom, rep, tree, Q)) return;
|
|
465 |
}
|
|
466 |
R.push(z);
|
|
467 |
}
|
|
468 |
} //for e
|
|
469 |
} // while ( !R.empty() )
|
|
470 |
}
|
|
471 |
|
|
472 |
void normShrink(Node v, typename Graph::template NodeMap<Node>& ear,
|
|
473 |
UFE& blossom, NV& rep, EFE& tree) {
|
|
474 |
//We have one tree, which we grow and shrink. If we augment then we
|
|
475 |
//return to the "for" cycle of runEdmonds().
|
|
476 |
|
|
477 |
std::queue<Node> Q; //queue of the unscanned nodes
|
|
478 |
Q.push(v);
|
|
479 |
while ( !Q.empty() ) {
|
|
480 |
|
|
481 |
Node x=Q.front();
|
|
482 |
Q.pop();
|
|
483 |
|
|
484 |
for( IncEdgeIt e(g,x); e!=INVALID; ++e ) {
|
|
485 |
Node y=g.runningNode(e);
|
|
486 |
|
|
487 |
switch ( position[y] ) {
|
|
488 |
case D: //x and y must be in the same tree
|
|
489 |
if ( blossom.find(x) != blossom.find(y))
|
|
490 |
//x and y are in the same tree
|
|
491 |
shrink(x, y, ear, blossom, rep, tree, Q);
|
|
492 |
break;
|
|
493 |
case C:
|
|
494 |
//growOrAugment grows if y is covered by the matching and
|
|
495 |
//augments if not. In this latter case it returns 1.
|
|
496 |
if (growOrAugment(y, x, ear, blossom, rep, tree, Q)) return;
|
|
497 |
break;
|
|
498 |
default: break;
|
|
499 |
}
|
|
500 |
}
|
|
501 |
}
|
|
502 |
}
|
|
503 |
|
|
504 |
void shrink(Node x,Node y, typename Graph::template NodeMap<Node>& ear,
|
|
505 |
UFE& blossom, NV& rep, EFE& tree,std::queue<Node>& Q) {
|
|
506 |
//x and y are the two adjacent vertices in two blossoms.
|
|
507 |
|
|
508 |
typename Graph::template NodeMap<bool> path(g,false);
|
|
509 |
|
|
510 |
Node b=rep[blossom.find(x)];
|
|
511 |
path.set(b,true);
|
|
512 |
b=_mate[b];
|
|
513 |
while ( b!=INVALID ) {
|
|
514 |
b=rep[blossom.find(ear[b])];
|
|
515 |
path.set(b,true);
|
|
516 |
b=_mate[b];
|
|
517 |
} //we go until the root through bases of blossoms and odd vertices
|
|
518 |
|
|
519 |
Node top=y;
|
|
520 |
Node middle=rep[blossom.find(top)];
|
|
521 |
Node bottom=x;
|
|
522 |
while ( !path[middle] )
|
|
523 |
shrinkStep(top, middle, bottom, ear, blossom, rep, tree, Q);
|
|
524 |
//Until we arrive to a node on the path, we update blossom, tree
|
|
525 |
//and the positions of the odd nodes.
|
|
526 |
|
|
527 |
Node base=middle;
|
|
528 |
top=x;
|
|
529 |
middle=rep[blossom.find(top)];
|
|
530 |
bottom=y;
|
|
531 |
Node blossom_base=rep[blossom.find(base)];
|
|
532 |
while ( middle!=blossom_base )
|
|
533 |
shrinkStep(top, middle, bottom, ear, blossom, rep, tree, Q);
|
|
534 |
//Until we arrive to a node on the path, we update blossom, tree
|
|
535 |
//and the positions of the odd nodes.
|
|
536 |
|
|
537 |
rep[blossom.find(base)] = base;
|
|
538 |
}
|
|
539 |
|
|
540 |
void shrinkStep(Node& top, Node& middle, Node& bottom,
|
|
541 |
typename Graph::template NodeMap<Node>& ear,
|
|
542 |
UFE& blossom, NV& rep, EFE& tree, std::queue<Node>& Q) {
|
|
543 |
//We traverse a blossom and update everything.
|
|
544 |
|
|
545 |
ear.set(top,bottom);
|
|
546 |
Node t=top;
|
|
547 |
while ( t!=middle ) {
|
|
548 |
Node u=_mate[t];
|
|
549 |
t=ear[u];
|
|
550 |
ear.set(t,u);
|
|
551 |
}
|
|
552 |
bottom=_mate[middle];
|
|
553 |
position.set(bottom,D);
|
|
554 |
Q.push(bottom);
|
|
555 |
top=ear[bottom];
|
|
556 |
Node oldmiddle=middle;
|
|
557 |
middle=rep[blossom.find(top)];
|
|
558 |
tree.erase(bottom);
|
|
559 |
tree.erase(oldmiddle);
|
|
560 |
blossom.insert(bottom);
|
|
561 |
blossom.join(bottom, oldmiddle);
|
|
562 |
blossom.join(top, oldmiddle);
|
|
563 |
}
|
|
564 |
|
|
565 |
|
|
566 |
|
|
567 |
bool growOrAugment(Node& y, Node& x, typename Graph::template
|
|
568 |
NodeMap<Node>& ear, UFE& blossom, NV& rep, EFE& tree,
|
|
569 |
std::queue<Node>& Q) {
|
|
570 |
//x is in a blossom in the tree, y is outside. If y is covered by
|
|
571 |
//the matching we grow, otherwise we augment. In this case we
|
|
572 |
//return 1.
|
|
573 |
|
|
574 |
if ( _mate[y]!=INVALID ) { //grow
|
|
575 |
ear.set(y,x);
|
|
576 |
Node w=_mate[y];
|
|
577 |
rep[blossom.insert(w)] = w;
|
|
578 |
position.set(y,A);
|
|
579 |
position.set(w,D);
|
|
580 |
int t = tree.find(rep[blossom.find(x)]);
|
|
581 |
tree.insert(y,t);
|
|
582 |
tree.insert(w,t);
|
|
583 |
Q.push(w);
|
|
584 |
} else { //augment
|
|
585 |
augment(x, ear, blossom, rep, tree);
|
|
586 |
_mate.set(x,y);
|
|
587 |
_mate.set(y,x);
|
|
588 |
return true;
|
|
589 |
}
|
|
590 |
return false;
|
|
591 |
}
|
|
592 |
|
|
593 |
void augment(Node x, typename Graph::template NodeMap<Node>& ear,
|
|
594 |
UFE& blossom, NV& rep, EFE& tree) {
|
|
595 |
Node v=_mate[x];
|
|
596 |
while ( v!=INVALID ) {
|
|
597 |
|
|
598 |
Node u=ear[v];
|
|
599 |
_mate.set(v,u);
|
|
600 |
Node tmp=v;
|
|
601 |
v=_mate[u];
|
|
602 |
_mate.set(u,tmp);
|
|
603 |
}
|
|
604 |
int y = tree.find(rep[blossom.find(x)]);
|
|
605 |
for (typename EFE::ItemIt tit(tree, y); tit != INVALID; ++tit) {
|
|
606 |
if ( position[tit] == D ) {
|
|
607 |
int b = blossom.find(tit);
|
|
608 |
for (typename UFE::ItemIt bit(blossom, b); bit != INVALID; ++bit) {
|
|
609 |
position.set(bit, C);
|
|
610 |
}
|
|
611 |
blossom.eraseClass(b);
|
|
612 |
} else position.set(tit, C);
|
|
613 |
}
|
|
614 |
tree.eraseClass(y);
|
|
615 |
|
|
616 |
}
|
|
617 |
|
|
618 |
};
|
|
619 |
|
|
620 |
/// \ingroup matching
|
|
621 |
///
|
|
622 |
/// \brief Weighted matching in general graphs
|
|
623 |
///
|
|
624 |
/// This class provides an efficient implementation of Edmond's
|
|
625 |
/// maximum weighted matching algorithm. The implementation is based
|
|
626 |
/// on extensive use of priority queues and provides
|
|
627 |
/// \f$O(nm\log(n))\f$ time complexity.
|
|
628 |
///
|
|
629 |
/// The maximum weighted matching problem is to find undirected
|
|
630 |
/// arcs in the digraph with maximum overall weight and no two of
|
|
631 |
/// them shares their endpoints. The problem can be formulated with
|
|
632 |
/// the next linear program:
|
|
633 |
/// \f[ \sum_{e \in \delta(u)}x_e \le 1 \quad \forall u\in V\f]
|
|
634 |
///\f[ \sum_{e \in \gamma(B)}x_e \le \frac{\vert B \vert - 1}{2} \quad \forall B\in\mathcal{O}\f]
|
|
635 |
/// \f[x_e \ge 0\quad \forall e\in E\f]
|
|
636 |
/// \f[\max \sum_{e\in E}x_ew_e\f]
|
|
637 |
/// where \f$\delta(X)\f$ is the set of arcs incident to a node in
|
|
638 |
/// \f$X\f$, \f$\gamma(X)\f$ is the set of arcs with both endpoints in
|
|
639 |
/// \f$X\f$ and \f$\mathcal{O}\f$ is the set of odd cardinality subsets of
|
|
640 |
/// the nodes.
|
|
641 |
///
|
|
642 |
/// The algorithm calculates an optimal matching and a proof of the
|
|
643 |
/// optimality. The solution of the dual problem can be used to check
|
|
644 |
/// the result of the algorithm. The dual linear problem is the next:
|
|
645 |
/// \f[ y_u + y_v + \sum_{B \in \mathcal{O}, uv \in \gamma(B)}z_B \ge w_{uv} \quad \forall uv\in E\f]
|
|
646 |
/// \f[y_u \ge 0 \quad \forall u \in V\f]
|
|
647 |
/// \f[z_B \ge 0 \quad \forall B \in \mathcal{O}\f]
|
|
648 |
/// \f[\min \sum_{u \in V}y_u + \sum_{B \in \mathcal{O}}\frac{\vert B \vert - 1}{2}z_B\f]
|
|
649 |
///
|
|
650 |
/// The algorithm can be executed with \c run() or the \c init() and
|
|
651 |
/// then the \c start() member functions. After it the matching can
|
|
652 |
/// be asked with \c matching() or mate() functions. The dual
|
|
653 |
/// solution can be get with \c nodeValue(), \c blossomNum() and \c
|
|
654 |
/// blossomValue() members and \ref MaxWeightedMatching::BlossomIt
|
|
655 |
/// "BlossomIt" nested class which is able to iterate on the nodes
|
|
656 |
/// of a blossom. If the value type is integral then the dual
|
|
657 |
/// solution is multiplied by \ref MaxWeightedMatching::dualScale "4".
|
|
658 |
template <typename _Graph,
|
|
659 |
typename _WeightMap = typename _Graph::template EdgeMap<int> >
|
|
660 |
class MaxWeightedMatching {
|
|
661 |
public:
|
|
662 |
|
|
663 |
typedef _Graph Graph;
|
|
664 |
typedef _WeightMap WeightMap;
|
|
665 |
typedef typename WeightMap::Value Value;
|
|
666 |
|
|
667 |
/// \brief Scaling factor for dual solution
|
|
668 |
///
|
|
669 |
/// Scaling factor for dual solution, it is equal to 4 or 1
|
|
670 |
/// according to the value type.
|
|
671 |
static const int dualScale =
|
|
672 |
std::numeric_limits<Value>::is_integer ? 4 : 1;
|
|
673 |
|
|
674 |
typedef typename Graph::template NodeMap<typename Graph::Arc>
|
|
675 |
MatchingMap;
|
|
676 |
|
|
677 |
private:
|
|
678 |
|
|
679 |
TEMPLATE_GRAPH_TYPEDEFS(Graph);
|
|
680 |
|
|
681 |
typedef typename Graph::template NodeMap<Value> NodePotential;
|
|
682 |
typedef std::vector<Node> BlossomNodeList;
|
|
683 |
|
|
684 |
struct BlossomVariable {
|
|
685 |
int begin, end;
|
|
686 |
Value value;
|
|
687 |
|
|
688 |
BlossomVariable(int _begin, int _end, Value _value)
|
|
689 |
: begin(_begin), end(_end), value(_value) {}
|
|
690 |
|
|
691 |
};
|
|
692 |
|
|
693 |
typedef std::vector<BlossomVariable> BlossomPotential;
|
|
694 |
|
|
695 |
const Graph& _graph;
|
|
696 |
const WeightMap& _weight;
|
|
697 |
|
|
698 |
MatchingMap* _matching;
|
|
699 |
|
|
700 |
NodePotential* _node_potential;
|
|
701 |
|
|
702 |
BlossomPotential _blossom_potential;
|
|
703 |
BlossomNodeList _blossom_node_list;
|
|
704 |
|
|
705 |
int _node_num;
|
|
706 |
int _blossom_num;
|
|
707 |
|
|
708 |
typedef typename Graph::template NodeMap<int> NodeIntMap;
|
|
709 |
typedef typename Graph::template ArcMap<int> ArcIntMap;
|
|
710 |
typedef typename Graph::template EdgeMap<int> EdgeIntMap;
|
|
711 |
typedef RangeMap<int> IntIntMap;
|
|
712 |
|
|
713 |
enum Status {
|
|
714 |
EVEN = -1, MATCHED = 0, ODD = 1, UNMATCHED = -2
|
|
715 |
};
|
|
716 |
|
|
717 |
typedef HeapUnionFind<Value, NodeIntMap> BlossomSet;
|
|
718 |
struct BlossomData {
|
|
719 |
int tree;
|
|
720 |
Status status;
|
|
721 |
Arc pred, next;
|
|
722 |
Value pot, offset;
|
|
723 |
Node base;
|
|
724 |
};
|
|
725 |
|
|
726 |
NodeIntMap *_blossom_index;
|
|
727 |
BlossomSet *_blossom_set;
|
|
728 |
RangeMap<BlossomData>* _blossom_data;
|
|
729 |
|
|
730 |
NodeIntMap *_node_index;
|
|
731 |
ArcIntMap *_node_heap_index;
|
|
732 |
|
|
733 |
struct NodeData {
|
|
734 |
|
|
735 |
NodeData(ArcIntMap& node_heap_index)
|
|
736 |
: heap(node_heap_index) {}
|
|
737 |
|
|
738 |
int blossom;
|
|
739 |
Value pot;
|
|
740 |
BinHeap<Value, ArcIntMap> heap;
|
|
741 |
std::map<int, Arc> heap_index;
|
|
742 |
|
|
743 |
int tree;
|
|
744 |
};
|
|
745 |
|
|
746 |
RangeMap<NodeData>* _node_data;
|
|
747 |
|
|
748 |
typedef ExtendFindEnum<IntIntMap> TreeSet;
|
|
749 |
|
|
750 |
IntIntMap *_tree_set_index;
|
|
751 |
TreeSet *_tree_set;
|
|
752 |
|
|
753 |
NodeIntMap *_delta1_index;
|
|
754 |
BinHeap<Value, NodeIntMap> *_delta1;
|
|
755 |
|
|
756 |
IntIntMap *_delta2_index;
|
|
757 |
BinHeap<Value, IntIntMap> *_delta2;
|
|
758 |
|
|
759 |
EdgeIntMap *_delta3_index;
|
|
760 |
BinHeap<Value, EdgeIntMap> *_delta3;
|
|
761 |
|
|
762 |
IntIntMap *_delta4_index;
|
|
763 |
BinHeap<Value, IntIntMap> *_delta4;
|
|
764 |
|
|
765 |
Value _delta_sum;
|
|
766 |
|
|
767 |
void createStructures() {
|
|
768 |
_node_num = countNodes(_graph);
|
|
769 |
_blossom_num = _node_num * 3 / 2;
|
|
770 |
|
|
771 |
if (!_matching) {
|
|
772 |
_matching = new MatchingMap(_graph);
|
|
773 |
}
|
|
774 |
if (!_node_potential) {
|
|
775 |
_node_potential = new NodePotential(_graph);
|
|
776 |
}
|
|
777 |
if (!_blossom_set) {
|
|
778 |
_blossom_index = new NodeIntMap(_graph);
|
|
779 |
_blossom_set = new BlossomSet(*_blossom_index);
|
|
780 |
_blossom_data = new RangeMap<BlossomData>(_blossom_num);
|
|
781 |
}
|
|
782 |
|
|
783 |
if (!_node_index) {
|
|
784 |
_node_index = new NodeIntMap(_graph);
|
|
785 |
_node_heap_index = new ArcIntMap(_graph);
|
|
786 |
_node_data = new RangeMap<NodeData>(_node_num,
|
|
787 |
NodeData(*_node_heap_index));
|
|
788 |
}
|
|
789 |
|
|
790 |
if (!_tree_set) {
|
|
791 |
_tree_set_index = new IntIntMap(_blossom_num);
|
|
792 |
_tree_set = new TreeSet(*_tree_set_index);
|
|
793 |
}
|
|
794 |
if (!_delta1) {
|
|
795 |
_delta1_index = new NodeIntMap(_graph);
|
|
796 |
_delta1 = new BinHeap<Value, NodeIntMap>(*_delta1_index);
|
|
797 |
}
|
|
798 |
if (!_delta2) {
|
|
799 |
_delta2_index = new IntIntMap(_blossom_num);
|
|
800 |
_delta2 = new BinHeap<Value, IntIntMap>(*_delta2_index);
|
|
801 |
}
|
|
802 |
if (!_delta3) {
|
|
803 |
_delta3_index = new EdgeIntMap(_graph);
|
|
804 |
_delta3 = new BinHeap<Value, EdgeIntMap>(*_delta3_index);
|
|
805 |
}
|
|
806 |
if (!_delta4) {
|
|
807 |
_delta4_index = new IntIntMap(_blossom_num);
|
|
808 |
_delta4 = new BinHeap<Value, IntIntMap>(*_delta4_index);
|
|
809 |
}
|
|
810 |
}
|
|
811 |
|
|
812 |
void destroyStructures() {
|
|
813 |
_node_num = countNodes(_graph);
|
|
814 |
_blossom_num = _node_num * 3 / 2;
|
|
815 |
|
|
816 |
if (_matching) {
|
|
817 |
delete _matching;
|
|
818 |
}
|
|
819 |
if (_node_potential) {
|
|
820 |
delete _node_potential;
|
|
821 |
}
|
|
822 |
if (_blossom_set) {
|
|
823 |
delete _blossom_index;
|
|
824 |
delete _blossom_set;
|
|
825 |
delete _blossom_data;
|
|
826 |
}
|
|
827 |
|
|
828 |
if (_node_index) {
|
|
829 |
delete _node_index;
|
|
830 |
delete _node_heap_index;
|
|
831 |
delete _node_data;
|
|
832 |
}
|
|
833 |
|
|
834 |
if (_tree_set) {
|
|
835 |
delete _tree_set_index;
|
|
836 |
delete _tree_set;
|
|
837 |
}
|
|
838 |
if (_delta1) {
|
|
839 |
delete _delta1_index;
|
|
840 |
delete _delta1;
|
|
841 |
}
|
|
842 |
if (_delta2) {
|
|
843 |
delete _delta2_index;
|
|
844 |
delete _delta2;
|
|
845 |
}
|
|
846 |
if (_delta3) {
|
|
847 |
delete _delta3_index;
|
|
848 |
delete _delta3;
|
|
849 |
}
|
|
850 |
if (_delta4) {
|
|
851 |
delete _delta4_index;
|
|
852 |
delete _delta4;
|
|
853 |
}
|
|
854 |
}
|
|
855 |
|
|
856 |
void matchedToEven(int blossom, int tree) {
|
|
857 |
if (_delta2->state(blossom) == _delta2->IN_HEAP) {
|
|
858 |
_delta2->erase(blossom);
|
|
859 |
}
|
|
860 |
|
|
861 |
if (!_blossom_set->trivial(blossom)) {
|
|
862 |
(*_blossom_data)[blossom].pot -=
|
|
863 |
2 * (_delta_sum - (*_blossom_data)[blossom].offset);
|
|
864 |
}
|
|
865 |
|
|
866 |
for (typename BlossomSet::ItemIt n(*_blossom_set, blossom);
|
|
867 |
n != INVALID; ++n) {
|
|
868 |
|
|
869 |
_blossom_set->increase(n, std::numeric_limits<Value>::max());
|
|
870 |
int ni = (*_node_index)[n];
|
|
871 |
|
|
872 |
(*_node_data)[ni].heap.clear();
|
|
873 |
(*_node_data)[ni].heap_index.clear();
|
|
874 |
|
|
875 |
(*_node_data)[ni].pot += _delta_sum - (*_blossom_data)[blossom].offset;
|
|
876 |
|
|
877 |
_delta1->push(n, (*_node_data)[ni].pot);
|
|
878 |
|
|
879 |
for (InArcIt e(_graph, n); e != INVALID; ++e) {
|
|
880 |
Node v = _graph.source(e);
|
|
881 |
int vb = _blossom_set->find(v);
|
|
882 |
int vi = (*_node_index)[v];
|
|
883 |
|
|
884 |
Value rw = (*_node_data)[ni].pot + (*_node_data)[vi].pot -
|
|
885 |
dualScale * _weight[e];
|
|
886 |
|
|
887 |
if ((*_blossom_data)[vb].status == EVEN) {
|
|
888 |
if (_delta3->state(e) != _delta3->IN_HEAP && blossom != vb) {
|
|
889 |
_delta3->push(e, rw / 2);
|
|
890 |
}
|
|
891 |
} else if ((*_blossom_data)[vb].status == UNMATCHED) {
|
|
892 |
if (_delta3->state(e) != _delta3->IN_HEAP) {
|
|
893 |
_delta3->push(e, rw);
|
|
894 |
}
|
|
895 |
} else {
|
|
896 |
typename std::map<int, Arc>::iterator it =
|
|
897 |
(*_node_data)[vi].heap_index.find(tree);
|
|
898 |
|
|
899 |
if (it != (*_node_data)[vi].heap_index.end()) {
|
|
900 |
if ((*_node_data)[vi].heap[it->second] > rw) {
|
|
901 |
(*_node_data)[vi].heap.replace(it->second, e);
|
|
902 |
(*_node_data)[vi].heap.decrease(e, rw);
|
|
903 |
it->second = e;
|
|
904 |
}
|
|
905 |
} else {
|
|
906 |
(*_node_data)[vi].heap.push(e, rw);
|
|
907 |
(*_node_data)[vi].heap_index.insert(std::make_pair(tree, e));
|
|
908 |
}
|
|
909 |
|
|
910 |
if ((*_blossom_set)[v] > (*_node_data)[vi].heap.prio()) {
|
|
911 |
_blossom_set->decrease(v, (*_node_data)[vi].heap.prio());
|
|
912 |
|
|
913 |
if ((*_blossom_data)[vb].status == MATCHED) {
|
|
914 |
if (_delta2->state(vb) != _delta2->IN_HEAP) {
|
|
915 |
_delta2->push(vb, _blossom_set->classPrio(vb) -
|
|
916 |
(*_blossom_data)[vb].offset);
|
|
917 |
} else if ((*_delta2)[vb] > _blossom_set->classPrio(vb) -
|
|
918 |
(*_blossom_data)[vb].offset){
|
|
919 |
_delta2->decrease(vb, _blossom_set->classPrio(vb) -
|
|
920 |
(*_blossom_data)[vb].offset);
|
|
921 |
}
|
|
922 |
}
|
|
923 |
}
|
|
924 |
}
|
|
925 |
}
|
|
926 |
}
|
|
927 |
(*_blossom_data)[blossom].offset = 0;
|
|
928 |
}
|
|
929 |
|
|
930 |
void matchedToOdd(int blossom) {
|
|
931 |
if (_delta2->state(blossom) == _delta2->IN_HEAP) {
|
|
932 |
_delta2->erase(blossom);
|
|
933 |
}
|
|
934 |
(*_blossom_data)[blossom].offset += _delta_sum;
|
|
935 |
if (!_blossom_set->trivial(blossom)) {
|
|
936 |
_delta4->push(blossom, (*_blossom_data)[blossom].pot / 2 +
|
|
937 |
(*_blossom_data)[blossom].offset);
|
|
938 |
}
|
|
939 |
}
|
|
940 |
|
|
941 |
void evenToMatched(int blossom, int tree) {
|
|
942 |
if (!_blossom_set->trivial(blossom)) {
|
|
943 |
(*_blossom_data)[blossom].pot += 2 * _delta_sum;
|
|
944 |
}
|
|
945 |
|
|
946 |
for (typename BlossomSet::ItemIt n(*_blossom_set, blossom);
|
|
947 |
n != INVALID; ++n) {
|
|
948 |
int ni = (*_node_index)[n];
|
|
949 |
(*_node_data)[ni].pot -= _delta_sum;
|
|
950 |
|
|
951 |
_delta1->erase(n);
|
|
952 |
|
|
953 |
for (InArcIt e(_graph, n); e != INVALID; ++e) {
|
|
954 |
Node v = _graph.source(e);
|
|
955 |
int vb = _blossom_set->find(v);
|
|
956 |
int vi = (*_node_index)[v];
|
|
957 |
|
|
958 |
Value rw = (*_node_data)[ni].pot + (*_node_data)[vi].pot -
|
|
959 |
dualScale * _weight[e];
|
|
960 |
|
|
961 |
if (vb == blossom) {
|
|
962 |
if (_delta3->state(e) == _delta3->IN_HEAP) {
|
|
963 |
_delta3->erase(e);
|
|
964 |
}
|
|
965 |
} else if ((*_blossom_data)[vb].status == EVEN) {
|
|
966 |
|
|
967 |
if (_delta3->state(e) == _delta3->IN_HEAP) {
|
|
968 |
_delta3->erase(e);
|
|
969 |
}
|
|
970 |
|
|
971 |
int vt = _tree_set->find(vb);
|
|
972 |
|
|
973 |
if (vt != tree) {
|
|
974 |
|
|
975 |
Arc r = _graph.oppositeArc(e);
|
|
976 |
|
|
977 |
typename std::map<int, Arc>::iterator it =
|
|
978 |
(*_node_data)[ni].heap_index.find(vt);
|
|
979 |
|
|
980 |
if (it != (*_node_data)[ni].heap_index.end()) {
|
|
981 |
if ((*_node_data)[ni].heap[it->second] > rw) {
|
|
982 |
(*_node_data)[ni].heap.replace(it->second, r);
|
|
983 |
(*_node_data)[ni].heap.decrease(r, rw);
|
|
984 |
it->second = r;
|
|
985 |
}
|
|
986 |
} else {
|
|
987 |
(*_node_data)[ni].heap.push(r, rw);
|
|
988 |
(*_node_data)[ni].heap_index.insert(std::make_pair(vt, r));
|
|
989 |
}
|
|
990 |
|
|
991 |
if ((*_blossom_set)[n] > (*_node_data)[ni].heap.prio()) {
|
|
992 |
_blossom_set->decrease(n, (*_node_data)[ni].heap.prio());
|
|
993 |
|
|
994 |
if (_delta2->state(blossom) != _delta2->IN_HEAP) {
|
|
995 |
_delta2->push(blossom, _blossom_set->classPrio(blossom) -
|
|
996 |
(*_blossom_data)[blossom].offset);
|
|
997 |
} else if ((*_delta2)[blossom] >
|
|
998 |
_blossom_set->classPrio(blossom) -
|
|
999 |
(*_blossom_data)[blossom].offset){
|
|
1000 |
_delta2->decrease(blossom, _blossom_set->classPrio(blossom) -
|
|
1001 |
(*_blossom_data)[blossom].offset);
|
|
1002 |
}
|
|
1003 |
}
|
|
1004 |
}
|
|
1005 |
|
|
1006 |
} else if ((*_blossom_data)[vb].status == UNMATCHED) {
|
|
1007 |
if (_delta3->state(e) == _delta3->IN_HEAP) {
|
|
1008 |
_delta3->erase(e);
|
|
1009 |
}
|
|
1010 |
} else {
|
|
1011 |
|
|
1012 |
typename std::map<int, Arc>::iterator it =
|
|
1013 |
(*_node_data)[vi].heap_index.find(tree);
|
|
1014 |
|
|
1015 |
if (it != (*_node_data)[vi].heap_index.end()) {
|
|
1016 |
(*_node_data)[vi].heap.erase(it->second);
|
|
1017 |
(*_node_data)[vi].heap_index.erase(it);
|
|
1018 |
if ((*_node_data)[vi].heap.empty()) {
|
|
1019 |
_blossom_set->increase(v, std::numeric_limits<Value>::max());
|
|
1020 |
} else if ((*_blossom_set)[v] < (*_node_data)[vi].heap.prio()) {
|
|
1021 |
_blossom_set->increase(v, (*_node_data)[vi].heap.prio());
|
|
1022 |
}
|
|
1023 |
|
|
1024 |
if ((*_blossom_data)[vb].status == MATCHED) {
|
|
1025 |
if (_blossom_set->classPrio(vb) ==
|
|
1026 |
std::numeric_limits<Value>::max()) {
|
|
1027 |
_delta2->erase(vb);
|
|
1028 |
} else if ((*_delta2)[vb] < _blossom_set->classPrio(vb) -
|
|
1029 |
(*_blossom_data)[vb].offset) {
|
|
1030 |
_delta2->increase(vb, _blossom_set->classPrio(vb) -
|
|
1031 |
(*_blossom_data)[vb].offset);
|
|
1032 |
}
|
|
1033 |
}
|
|
1034 |
}
|
|
1035 |
}
|
|
1036 |
}
|
|
1037 |
}
|
|
1038 |
}
|
|
1039 |
|
|
1040 |
void oddToMatched(int blossom) {
|
|
1041 |
(*_blossom_data)[blossom].offset -= _delta_sum;
|
|
1042 |
|
|
1043 |
if (_blossom_set->classPrio(blossom) !=
|
|
1044 |
std::numeric_limits<Value>::max()) {
|
|
1045 |
_delta2->push(blossom, _blossom_set->classPrio(blossom) -
|
|
1046 |
(*_blossom_data)[blossom].offset);
|
|
1047 |
}
|
|
1048 |
|
|
1049 |
if (!_blossom_set->trivial(blossom)) {
|
|
1050 |
_delta4->erase(blossom);
|
|
1051 |
}
|
|
1052 |
}
|
|
1053 |
|
|
1054 |
void oddToEven(int blossom, int tree) {
|
|
1055 |
if (!_blossom_set->trivial(blossom)) {
|
|
1056 |
_delta4->erase(blossom);
|
|
1057 |
(*_blossom_data)[blossom].pot -=
|
|
1058 |
2 * (2 * _delta_sum - (*_blossom_data)[blossom].offset);
|
|
1059 |
}
|
|
1060 |
|
|
1061 |
for (typename BlossomSet::ItemIt n(*_blossom_set, blossom);
|
|
1062 |
n != INVALID; ++n) {
|
|
1063 |
int ni = (*_node_index)[n];
|
|
1064 |
|
|
1065 |
_blossom_set->increase(n, std::numeric_limits<Value>::max());
|
|
1066 |
|
|
1067 |
(*_node_data)[ni].heap.clear();
|
|
1068 |
(*_node_data)[ni].heap_index.clear();
|
|
1069 |
(*_node_data)[ni].pot +=
|
|
1070 |
2 * _delta_sum - (*_blossom_data)[blossom].offset;
|
|
1071 |
|
|
1072 |
_delta1->push(n, (*_node_data)[ni].pot);
|
|
1073 |
|
|
1074 |
for (InArcIt e(_graph, n); e != INVALID; ++e) {
|
|
1075 |
Node v = _graph.source(e);
|
|
1076 |
int vb = _blossom_set->find(v);
|
|
1077 |
int vi = (*_node_index)[v];
|
|
1078 |
|
|
1079 |
Value rw = (*_node_data)[ni].pot + (*_node_data)[vi].pot -
|
|
1080 |
dualScale * _weight[e];
|
|
1081 |
|
|
1082 |
if ((*_blossom_data)[vb].status == EVEN) {
|
|
1083 |
if (_delta3->state(e) != _delta3->IN_HEAP && blossom != vb) {
|
|
1084 |
_delta3->push(e, rw / 2);
|
|
1085 |
}
|
|
1086 |
} else if ((*_blossom_data)[vb].status == UNMATCHED) {
|
|
1087 |
if (_delta3->state(e) != _delta3->IN_HEAP) {
|
|
1088 |
_delta3->push(e, rw);
|
|
1089 |
}
|
|
1090 |
} else {
|
|
1091 |
|
|
1092 |
typename std::map<int, Arc>::iterator it =
|
|
1093 |
(*_node_data)[vi].heap_index.find(tree);
|
|
1094 |
|
|
1095 |
if (it != (*_node_data)[vi].heap_index.end()) {
|
|
1096 |
if ((*_node_data)[vi].heap[it->second] > rw) {
|
|
1097 |
(*_node_data)[vi].heap.replace(it->second, e);
|
|
1098 |
(*_node_data)[vi].heap.decrease(e, rw);
|
|
1099 |
it->second = e;
|
|
1100 |
}
|
|
1101 |
} else {
|
|
1102 |
(*_node_data)[vi].heap.push(e, rw);
|
|
1103 |
(*_node_data)[vi].heap_index.insert(std::make_pair(tree, e));
|
|
1104 |
}
|
|
1105 |
|
|
1106 |
if ((*_blossom_set)[v] > (*_node_data)[vi].heap.prio()) {
|
|
1107 |
_blossom_set->decrease(v, (*_node_data)[vi].heap.prio());
|
|
1108 |
|
|
1109 |
if ((*_blossom_data)[vb].status == MATCHED) {
|
|
1110 |
if (_delta2->state(vb) != _delta2->IN_HEAP) {
|
|
1111 |
_delta2->push(vb, _blossom_set->classPrio(vb) -
|
|
1112 |
(*_blossom_data)[vb].offset);
|
|
1113 |
} else if ((*_delta2)[vb] > _blossom_set->classPrio(vb) -
|
|
1114 |
(*_blossom_data)[vb].offset) {
|
|
1115 |
_delta2->decrease(vb, _blossom_set->classPrio(vb) -
|
|
1116 |
(*_blossom_data)[vb].offset);
|
|
1117 |
}
|
|
1118 |
}
|
|
1119 |
}
|
|
1120 |
}
|
|
1121 |
}
|
|
1122 |
}
|
|
1123 |
(*_blossom_data)[blossom].offset = 0;
|
|
1124 |
}
|
|
1125 |
|
|
1126 |
|
|
1127 |
void matchedToUnmatched(int blossom) {
|
|
1128 |
if (_delta2->state(blossom) == _delta2->IN_HEAP) {
|
|
1129 |
_delta2->erase(blossom);
|
|
1130 |
}
|
|
1131 |
|
|
1132 |
for (typename BlossomSet::ItemIt n(*_blossom_set, blossom);
|
|
1133 |
n != INVALID; ++n) {
|
|
1134 |
int ni = (*_node_index)[n];
|
|
1135 |
|
|
1136 |
_blossom_set->increase(n, std::numeric_limits<Value>::max());
|
|
1137 |
|
|
1138 |
(*_node_data)[ni].heap.clear();
|
|
1139 |
(*_node_data)[ni].heap_index.clear();
|
|
1140 |
|
|
1141 |
for (OutArcIt e(_graph, n); e != INVALID; ++e) {
|
|
1142 |
Node v = _graph.target(e);
|
|
1143 |
int vb = _blossom_set->find(v);
|
|
1144 |
int vi = (*_node_index)[v];
|
|
1145 |
|
|
1146 |
Value rw = (*_node_data)[ni].pot + (*_node_data)[vi].pot -
|
|
1147 |
dualScale * _weight[e];
|
|
1148 |
|
|
1149 |
if ((*_blossom_data)[vb].status == EVEN) {
|
|
1150 |
if (_delta3->state(e) != _delta3->IN_HEAP) {
|
|
1151 |
_delta3->push(e, rw);
|
|
1152 |
}
|
|
1153 |
}
|
|
1154 |
}
|
|
1155 |
}
|
|
1156 |
}
|
|
1157 |
|
|
1158 |
void unmatchedToMatched(int blossom) {
|
|
1159 |
for (typename BlossomSet::ItemIt n(*_blossom_set, blossom);
|
|
1160 |
n != INVALID; ++n) {
|
|
1161 |
int ni = (*_node_index)[n];
|
|
1162 |
|
|
1163 |
for (InArcIt e(_graph, n); e != INVALID; ++e) {
|
|
1164 |
Node v = _graph.source(e);
|
|
1165 |
int vb = _blossom_set->find(v);
|
|
1166 |
int vi = (*_node_index)[v];
|
|
1167 |
|
|
1168 |
Value rw = (*_node_data)[ni].pot + (*_node_data)[vi].pot -
|
|
1169 |
dualScale * _weight[e];
|
|
1170 |
|
|
1171 |
if (vb == blossom) {
|
|
1172 |
if (_delta3->state(e) == _delta3->IN_HEAP) {
|
|
1173 |
_delta3->erase(e);
|
|
1174 |
}
|
|
1175 |
} else if ((*_blossom_data)[vb].status == EVEN) {
|
|
1176 |
|
|
1177 |
if (_delta3->state(e) == _delta3->IN_HEAP) {
|
|
1178 |
_delta3->erase(e);
|
|
1179 |
}
|
|
1180 |
|
|
1181 |
int vt = _tree_set->find(vb);
|
|
1182 |
|
|
1183 |
Arc r = _graph.oppositeArc(e);
|
|
1184 |
|
|
1185 |
typename std::map<int, Arc>::iterator it =
|
|
1186 |
(*_node_data)[ni].heap_index.find(vt);
|
|
1187 |
|
|
1188 |
if (it != (*_node_data)[ni].heap_index.end()) {
|
|
1189 |
if ((*_node_data)[ni].heap[it->second] > rw) {
|
|
1190 |
(*_node_data)[ni].heap.replace(it->second, r);
|
|
1191 |
(*_node_data)[ni].heap.decrease(r, rw);
|
|
1192 |
it->second = r;
|
|
1193 |
}
|
|
1194 |
} else {
|
|
1195 |
(*_node_data)[ni].heap.push(r, rw);
|
|
1196 |
(*_node_data)[ni].heap_index.insert(std::make_pair(vt, r));
|
|
1197 |
}
|
|
1198 |
|
|
1199 |
if ((*_blossom_set)[n] > (*_node_data)[ni].heap.prio()) {
|
|
1200 |
_blossom_set->decrease(n, (*_node_data)[ni].heap.prio());
|
|
1201 |
|
|
1202 |
if (_delta2->state(blossom) != _delta2->IN_HEAP) {
|
|
1203 |
_delta2->push(blossom, _blossom_set->classPrio(blossom) -
|
|
1204 |
(*_blossom_data)[blossom].offset);
|
|
1205 |
} else if ((*_delta2)[blossom] > _blossom_set->classPrio(blossom)-
|
|
1206 |
(*_blossom_data)[blossom].offset){
|
|
1207 |
_delta2->decrease(blossom, _blossom_set->classPrio(blossom) -
|
|
1208 |
(*_blossom_data)[blossom].offset);
|
|
1209 |
}
|
|
1210 |
}
|
|
1211 |
|
|
1212 |
} else if ((*_blossom_data)[vb].status == UNMATCHED) {
|
|
1213 |
if (_delta3->state(e) == _delta3->IN_HEAP) {
|
|
1214 |
_delta3->erase(e);
|
|
1215 |
}
|
|
1216 |
}
|
|
1217 |
}
|
|
1218 |
}
|
|
1219 |
}
|
|
1220 |
|
|
1221 |
void alternatePath(int even, int tree) {
|
|
1222 |
int odd;
|
|
1223 |
|
|
1224 |
evenToMatched(even, tree);
|
|
1225 |
(*_blossom_data)[even].status = MATCHED;
|
|
1226 |
|
|
1227 |
while ((*_blossom_data)[even].pred != INVALID) {
|
|
1228 |
odd = _blossom_set->find(_graph.target((*_blossom_data)[even].pred));
|
|
1229 |
(*_blossom_data)[odd].status = MATCHED;
|
|
1230 |
oddToMatched(odd);
|
|
1231 |
(*_blossom_data)[odd].next = (*_blossom_data)[odd].pred;
|
|
1232 |
|
|
1233 |
even = _blossom_set->find(_graph.target((*_blossom_data)[odd].pred));
|
|
1234 |
(*_blossom_data)[even].status = MATCHED;
|
|
1235 |
evenToMatched(even, tree);
|
|
1236 |
(*_blossom_data)[even].next =
|
|
1237 |
_graph.oppositeArc((*_blossom_data)[odd].pred);
|
|
1238 |
}
|
|
1239 |
|
|
1240 |
}
|
|
1241 |
|
|
1242 |
void destroyTree(int tree) {
|
|
1243 |
for (TreeSet::ItemIt b(*_tree_set, tree); b != INVALID; ++b) {
|
|
1244 |
if ((*_blossom_data)[b].status == EVEN) {
|
|
1245 |
(*_blossom_data)[b].status = MATCHED;
|
|
1246 |
evenToMatched(b, tree);
|
|
1247 |
} else if ((*_blossom_data)[b].status == ODD) {
|
|
1248 |
(*_blossom_data)[b].status = MATCHED;
|
|
1249 |
oddToMatched(b);
|
|
1250 |
}
|
|
1251 |
}
|
|
1252 |
_tree_set->eraseClass(tree);
|
|
1253 |
}
|
|
1254 |
|
|
1255 |
|
|
1256 |
void unmatchNode(const Node& node) {
|
|
1257 |
int blossom = _blossom_set->find(node);
|
|
1258 |
int tree = _tree_set->find(blossom);
|
|
1259 |
|
|
1260 |
alternatePath(blossom, tree);
|
|
1261 |
destroyTree(tree);
|
|
1262 |
|
|
1263 |
(*_blossom_data)[blossom].status = UNMATCHED;
|
|
1264 |
(*_blossom_data)[blossom].base = node;
|
|
1265 |
matchedToUnmatched(blossom);
|
|
1266 |
}
|
|
1267 |
|
|
1268 |
|
|
1269 |
void augmentOnArc(const Edge& arc) {
|
|
1270 |
|
|
1271 |
int left = _blossom_set->find(_graph.u(arc));
|
|
1272 |
int right = _blossom_set->find(_graph.v(arc));
|
|
1273 |
|
|
1274 |
if ((*_blossom_data)[left].status == EVEN) {
|
|
1275 |
int left_tree = _tree_set->find(left);
|
|
1276 |
alternatePath(left, left_tree);
|
|
1277 |
destroyTree(left_tree);
|
|
1278 |
} else {
|
|
1279 |
(*_blossom_data)[left].status = MATCHED;
|
|
1280 |
unmatchedToMatched(left);
|
|
1281 |
}
|
|
1282 |
|
|
1283 |
if ((*_blossom_data)[right].status == EVEN) {
|
|
1284 |
int right_tree = _tree_set->find(right);
|
|
1285 |
alternatePath(right, right_tree);
|
|
1286 |
destroyTree(right_tree);
|
|
1287 |
} else {
|
|
1288 |
(*_blossom_data)[right].status = MATCHED;
|
|
1289 |
unmatchedToMatched(right);
|
|
1290 |
}
|
|
1291 |
|
|
1292 |
(*_blossom_data)[left].next = _graph.direct(arc, true);
|
|
1293 |
(*_blossom_data)[right].next = _graph.direct(arc, false);
|
|
1294 |
}
|
|
1295 |
|
|
1296 |
void extendOnArc(const Arc& arc) {
|
|
1297 |
int base = _blossom_set->find(_graph.target(arc));
|
|
1298 |
int tree = _tree_set->find(base);
|
|
1299 |
|
|
1300 |
int odd = _blossom_set->find(_graph.source(arc));
|
|
1301 |
_tree_set->insert(odd, tree);
|
|
1302 |
(*_blossom_data)[odd].status = ODD;
|
|
1303 |
matchedToOdd(odd);
|
|
1304 |
(*_blossom_data)[odd].pred = arc;
|
|
1305 |
|
|
1306 |
int even = _blossom_set->find(_graph.target((*_blossom_data)[odd].next));
|
|
1307 |
(*_blossom_data)[even].pred = (*_blossom_data)[even].next;
|
|
1308 |
_tree_set->insert(even, tree);
|
|
1309 |
(*_blossom_data)[even].status = EVEN;
|
|
1310 |
matchedToEven(even, tree);
|
|
1311 |
}
|
|
1312 |
|
|
1313 |
void shrinkOnArc(const Edge& edge, int tree) {
|
|
1314 |
int nca = -1;
|
|
1315 |
std::vector<int> left_path, right_path;
|
|
1316 |
|
|
1317 |
{
|
|
1318 |
std::set<int> left_set, right_set;
|
|
1319 |
int left = _blossom_set->find(_graph.u(edge));
|
|
1320 |
left_path.push_back(left);
|
|
1321 |
left_set.insert(left);
|
|
1322 |
|
|
1323 |
int right = _blossom_set->find(_graph.v(edge));
|
|
1324 |
right_path.push_back(right);
|
|
1325 |
right_set.insert(right);
|
|
1326 |
|
|
1327 |
while (true) {
|
|
1328 |
|
|
1329 |
if ((*_blossom_data)[left].pred == INVALID) break;
|
|
1330 |
|
|
1331 |
left =
|
|
1332 |
_blossom_set->find(_graph.target((*_blossom_data)[left].pred));
|
|
1333 |
left_path.push_back(left);
|
|
1334 |
left =
|
|
1335 |
_blossom_set->find(_graph.target((*_blossom_data)[left].pred));
|
|
1336 |
left_path.push_back(left);
|
|
1337 |
|
|
1338 |
left_set.insert(left);
|
|
1339 |
|
|
1340 |
if (right_set.find(left) != right_set.end()) {
|
|
1341 |
nca = left;
|
|
1342 |
break;
|
|
1343 |
}
|
|
1344 |
|
|
1345 |
if ((*_blossom_data)[right].pred == INVALID) break;
|
|
1346 |
|
|
1347 |
right =
|
|
1348 |
_blossom_set->find(_graph.target((*_blossom_data)[right].pred));
|
|
1349 |
right_path.push_back(right);
|
|
1350 |
right =
|
|
1351 |
_blossom_set->find(_graph.target((*_blossom_data)[right].pred));
|
|
1352 |
right_path.push_back(right);
|
|
1353 |
|
|
1354 |
right_set.insert(right);
|
|
1355 |
|
|
1356 |
if (left_set.find(right) != left_set.end()) {
|
|
1357 |
nca = right;
|
|
1358 |
break;
|
|
1359 |
}
|
|
1360 |
|
|
1361 |
}
|
|
1362 |
|
|
1363 |
if (nca == -1) {
|
|
1364 |
if ((*_blossom_data)[left].pred == INVALID) {
|
|
1365 |
nca = right;
|
|
1366 |
while (left_set.find(nca) == left_set.end()) {
|
|
1367 |
nca =
|
|
1368 |
_blossom_set->find(_graph.target((*_blossom_data)[nca].pred));
|
|
1369 |
right_path.push_back(nca);
|
|
1370 |
nca =
|
|
1371 |
_blossom_set->find(_graph.target((*_blossom_data)[nca].pred));
|
|
1372 |
right_path.push_back(nca);
|
|
1373 |
}
|
|
1374 |
} else {
|
|
1375 |
nca = left;
|
|
1376 |
while (right_set.find(nca) == right_set.end()) {
|
|
1377 |
nca =
|
|
1378 |
_blossom_set->find(_graph.target((*_blossom_data)[nca].pred));
|
|
1379 |
left_path.push_back(nca);
|
|
1380 |
nca =
|
|
1381 |
_blossom_set->find(_graph.target((*_blossom_data)[nca].pred));
|
|
1382 |
left_path.push_back(nca);
|
|
1383 |
}
|
|
1384 |
}
|
|
1385 |
}
|
|
1386 |
}
|
|
1387 |
|
|
1388 |
std::vector<int> subblossoms;
|
|
1389 |
Arc prev;
|
|
1390 |
|
|
1391 |
prev = _graph.direct(edge, true);
|
|
1392 |
for (int i = 0; left_path[i] != nca; i += 2) {
|
|
1393 |
subblossoms.push_back(left_path[i]);
|
|
1394 |
(*_blossom_data)[left_path[i]].next = prev;
|
|
1395 |
_tree_set->erase(left_path[i]);
|
|
1396 |
|
|
1397 |
subblossoms.push_back(left_path[i + 1]);
|
|
1398 |
(*_blossom_data)[left_path[i + 1]].status = EVEN;
|
|
1399 |
oddToEven(left_path[i + 1], tree);
|
|
1400 |
_tree_set->erase(left_path[i + 1]);
|
|
1401 |
prev = _graph.oppositeArc((*_blossom_data)[left_path[i + 1]].pred);
|
|
1402 |
}
|
|
1403 |
|
|
1404 |
int k = 0;
|
|
1405 |
while (right_path[k] != nca) ++k;
|
|
1406 |
|
|
1407 |
subblossoms.push_back(nca);
|
|
1408 |
(*_blossom_data)[nca].next = prev;
|
|
1409 |
|
|
1410 |
for (int i = k - 2; i >= 0; i -= 2) {
|
|
1411 |
subblossoms.push_back(right_path[i + 1]);
|
|
1412 |
(*_blossom_data)[right_path[i + 1]].status = EVEN;
|
|
1413 |
oddToEven(right_path[i + 1], tree);
|
|
1414 |
_tree_set->erase(right_path[i + 1]);
|
|
1415 |
|
|
1416 |
(*_blossom_data)[right_path[i + 1]].next =
|
|
1417 |
(*_blossom_data)[right_path[i + 1]].pred;
|
|
1418 |
|
|
1419 |
subblossoms.push_back(right_path[i]);
|
|
1420 |
_tree_set->erase(right_path[i]);
|
|
1421 |
}
|
|
1422 |
|
|
1423 |
int surface =
|
|
1424 |
_blossom_set->join(subblossoms.begin(), subblossoms.end());
|
|
1425 |
|
|
1426 |
for (int i = 0; i < int(subblossoms.size()); ++i) {
|
|
1427 |
if (!_blossom_set->trivial(subblossoms[i])) {
|
|
1428 |
(*_blossom_data)[subblossoms[i]].pot += 2 * _delta_sum;
|
|
1429 |
}
|
|
1430 |
(*_blossom_data)[subblossoms[i]].status = MATCHED;
|
|
1431 |
}
|
|
1432 |
|
|
1433 |
(*_blossom_data)[surface].pot = -2 * _delta_sum;
|
|
1434 |
(*_blossom_data)[surface].offset = 0;
|
|
1435 |
(*_blossom_data)[surface].status = EVEN;
|
|
1436 |
(*_blossom_data)[surface].pred = (*_blossom_data)[nca].pred;
|
|
1437 |
(*_blossom_data)[surface].next = (*_blossom_data)[nca].pred;
|
|
1438 |
|
|
1439 |
_tree_set->insert(surface, tree);
|
|
1440 |
_tree_set->erase(nca);
|
|
1441 |
}
|
|
1442 |
|
|
1443 |
void splitBlossom(int blossom) {
|
|
1444 |
Arc next = (*_blossom_data)[blossom].next;
|
|
1445 |
Arc pred = (*_blossom_data)[blossom].pred;
|
|
1446 |
|
|
1447 |
int tree = _tree_set->find(blossom);
|
|
1448 |
|
|
1449 |
(*_blossom_data)[blossom].status = MATCHED;
|
|
1450 |
oddToMatched(blossom);
|
|
1451 |
if (_delta2->state(blossom) == _delta2->IN_HEAP) {
|
|
1452 |
_delta2->erase(blossom);
|
|
1453 |
}
|
|
1454 |
|
|
1455 |
std::vector<int> subblossoms;
|
|
1456 |
_blossom_set->split(blossom, std::back_inserter(subblossoms));
|
|
1457 |
|
|
1458 |
Value offset = (*_blossom_data)[blossom].offset;
|
|
1459 |
int b = _blossom_set->find(_graph.source(pred));
|
|
1460 |
int d = _blossom_set->find(_graph.source(next));
|
|
1461 |
|
|
1462 |
int ib = -1, id = -1;
|
|
1463 |
for (int i = 0; i < int(subblossoms.size()); ++i) {
|
|
1464 |
if (subblossoms[i] == b) ib = i;
|
|
1465 |
if (subblossoms[i] == d) id = i;
|
|
1466 |
|
|
1467 |
(*_blossom_data)[subblossoms[i]].offset = offset;
|
|
1468 |
if (!_blossom_set->trivial(subblossoms[i])) {
|
|
1469 |
(*_blossom_data)[subblossoms[i]].pot -= 2 * offset;
|
|
1470 |
}
|
|
1471 |
if (_blossom_set->classPrio(subblossoms[i]) !=
|
|
1472 |
std::numeric_limits<Value>::max()) {
|
|
1473 |
_delta2->push(subblossoms[i],
|
|
1474 |
_blossom_set->classPrio(subblossoms[i]) -
|
|
1475 |
(*_blossom_data)[subblossoms[i]].offset);
|
|
1476 |
}
|
|
1477 |
}
|
|
1478 |
|
|
1479 |
if (id > ib ? ((id - ib) % 2 == 0) : ((ib - id) % 2 == 1)) {
|
|
1480 |
for (int i = (id + 1) % subblossoms.size();
|
|
1481 |
i != ib; i = (i + 2) % subblossoms.size()) {
|
|
1482 |
int sb = subblossoms[i];
|
|
1483 |
int tb = subblossoms[(i + 1) % subblossoms.size()];
|
|
1484 |
(*_blossom_data)[sb].next =
|
|
1485 |
_graph.oppositeArc((*_blossom_data)[tb].next);
|
|
1486 |
}
|
|
1487 |
|
|
1488 |
for (int i = ib; i != id; i = (i + 2) % subblossoms.size()) {
|
|
1489 |
int sb = subblossoms[i];
|
|
1490 |
int tb = subblossoms[(i + 1) % subblossoms.size()];
|
|
1491 |
int ub = subblossoms[(i + 2) % subblossoms.size()];
|
|
1492 |
|
|
1493 |
(*_blossom_data)[sb].status = ODD;
|
|
1494 |
matchedToOdd(sb);
|
|
1495 |
_tree_set->insert(sb, tree);
|
|
1496 |
(*_blossom_data)[sb].pred = pred;
|
|
1497 |
(*_blossom_data)[sb].next =
|
|
1498 |
_graph.oppositeArc((*_blossom_data)[tb].next);
|
|
1499 |
|
|
1500 |
pred = (*_blossom_data)[ub].next;
|
|
1501 |
|
|
1502 |
(*_blossom_data)[tb].status = EVEN;
|
|
1503 |
matchedToEven(tb, tree);
|
|
1504 |
_tree_set->insert(tb, tree);
|
|
1505 |
(*_blossom_data)[tb].pred = (*_blossom_data)[tb].next;
|
|
1506 |
}
|
|
1507 |
|
|
1508 |
(*_blossom_data)[subblossoms[id]].status = ODD;
|
|
1509 |
matchedToOdd(subblossoms[id]);
|
|
1510 |
_tree_set->insert(subblossoms[id], tree);
|
|
1511 |
(*_blossom_data)[subblossoms[id]].next = next;
|
|
1512 |
(*_blossom_data)[subblossoms[id]].pred = pred;
|
|
1513 |
|
|
1514 |
} else {
|
|
1515 |
|
|
1516 |
for (int i = (ib + 1) % subblossoms.size();
|
|
1517 |
i != id; i = (i + 2) % subblossoms.size()) {
|
|
1518 |
int sb = subblossoms[i];
|
|
1519 |
int tb = subblossoms[(i + 1) % subblossoms.size()];
|
|
1520 |
(*_blossom_data)[sb].next =
|
|
1521 |
_graph.oppositeArc((*_blossom_data)[tb].next);
|
|
1522 |
}
|
|
1523 |
|
|
1524 |
for (int i = id; i != ib; i = (i + 2) % subblossoms.size()) {
|
|
1525 |
int sb = subblossoms[i];
|
|
1526 |
int tb = subblossoms[(i + 1) % subblossoms.size()];
|
|
1527 |
int ub = subblossoms[(i + 2) % subblossoms.size()];
|
|
1528 |
|
|
1529 |
(*_blossom_data)[sb].status = ODD;
|
|
1530 |
matchedToOdd(sb);
|
|
1531 |
_tree_set->insert(sb, tree);
|
|
1532 |
(*_blossom_data)[sb].next = next;
|
|
1533 |
(*_blossom_data)[sb].pred =
|
|
1534 |
_graph.oppositeArc((*_blossom_data)[tb].next);
|
|
1535 |
|
|
1536 |
(*_blossom_data)[tb].status = EVEN;
|
|
1537 |
matchedToEven(tb, tree);
|
|
1538 |
_tree_set->insert(tb, tree);
|
|
1539 |
(*_blossom_data)[tb].pred =
|
|
1540 |
(*_blossom_data)[tb].next =
|
|
1541 |
_graph.oppositeArc((*_blossom_data)[ub].next);
|
|
1542 |
next = (*_blossom_data)[ub].next;
|
|
1543 |
}
|
|
1544 |
|
|
1545 |
(*_blossom_data)[subblossoms[ib]].status = ODD;
|
|
1546 |
matchedToOdd(subblossoms[ib]);
|
|
1547 |
_tree_set->insert(subblossoms[ib], tree);
|
|
1548 |
(*_blossom_data)[subblossoms[ib]].next = next;
|
|
1549 |
(*_blossom_data)[subblossoms[ib]].pred = pred;
|
|
1550 |
}
|
|
1551 |
_tree_set->erase(blossom);
|
|
1552 |
}
|
|
1553 |
|
|
1554 |
void extractBlossom(int blossom, const Node& base, const Arc& matching) {
|
|
1555 |
if (_blossom_set->trivial(blossom)) {
|
|
1556 |
int bi = (*_node_index)[base];
|
|
1557 |
Value pot = (*_node_data)[bi].pot;
|
|
1558 |
|
|
1559 |
_matching->set(base, matching);
|
|
1560 |
_blossom_node_list.push_back(base);
|
|
1561 |
_node_potential->set(base, pot);
|
|
1562 |
} else {
|
|
1563 |
|
|
1564 |
Value pot = (*_blossom_data)[blossom].pot;
|
|
1565 |
int bn = _blossom_node_list.size();
|
|
1566 |
|
|
1567 |
std::vector<int> subblossoms;
|
|
1568 |
_blossom_set->split(blossom, std::back_inserter(subblossoms));
|
|
1569 |
int b = _blossom_set->find(base);
|
|
1570 |
int ib = -1;
|
|
1571 |
for (int i = 0; i < int(subblossoms.size()); ++i) {
|
|
1572 |
if (subblossoms[i] == b) { ib = i; break; }
|
|
1573 |
}
|
|
1574 |
|
|
1575 |
for (int i = 1; i < int(subblossoms.size()); i += 2) {
|
|
1576 |
int sb = subblossoms[(ib + i) % subblossoms.size()];
|
|
1577 |
int tb = subblossoms[(ib + i + 1) % subblossoms.size()];
|
|
1578 |
|
|
1579 |
Arc m = (*_blossom_data)[tb].next;
|
|
1580 |
extractBlossom(sb, _graph.target(m), _graph.oppositeArc(m));
|
|
1581 |
extractBlossom(tb, _graph.source(m), m);
|
|
1582 |
}
|
|
1583 |
extractBlossom(subblossoms[ib], base, matching);
|
|
1584 |
|
|
1585 |
int en = _blossom_node_list.size();
|
|
1586 |
|
|
1587 |
_blossom_potential.push_back(BlossomVariable(bn, en, pot));
|
|
1588 |
}
|
|
1589 |
}
|
|
1590 |
|
|
1591 |
void extractMatching() {
|
|
1592 |
std::vector<int> blossoms;
|
|
1593 |
for (typename BlossomSet::ClassIt c(*_blossom_set); c != INVALID; ++c) {
|
|
1594 |
blossoms.push_back(c);
|
|
1595 |
}
|
|
1596 |
|
|
1597 |
for (int i = 0; i < int(blossoms.size()); ++i) {
|
|
1598 |
if ((*_blossom_data)[blossoms[i]].status == MATCHED) {
|
|
1599 |
|
|
1600 |
Value offset = (*_blossom_data)[blossoms[i]].offset;
|
|
1601 |
(*_blossom_data)[blossoms[i]].pot += 2 * offset;
|
|
1602 |
for (typename BlossomSet::ItemIt n(*_blossom_set, blossoms[i]);
|
|
1603 |
n != INVALID; ++n) {
|
|
1604 |
(*_node_data)[(*_node_index)[n]].pot -= offset;
|
|
1605 |
}
|
|
1606 |
|
|
1607 |
Arc matching = (*_blossom_data)[blossoms[i]].next;
|
|
1608 |
Node base = _graph.source(matching);
|
|
1609 |
extractBlossom(blossoms[i], base, matching);
|
|
1610 |
} else {
|
|
1611 |
Node base = (*_blossom_data)[blossoms[i]].base;
|
|
1612 |
extractBlossom(blossoms[i], base, INVALID);
|
|
1613 |
}
|
|
1614 |
}
|
|
1615 |
}
|
|
1616 |
|
|
1617 |
public:
|
|
1618 |
|
|
1619 |
/// \brief Constructor
|
|
1620 |
///
|
|
1621 |
/// Constructor.
|
|
1622 |
MaxWeightedMatching(const Graph& graph, const WeightMap& weight)
|
|
1623 |
: _graph(graph), _weight(weight), _matching(0),
|
|
1624 |
_node_potential(0), _blossom_potential(), _blossom_node_list(),
|
|
1625 |
_node_num(0), _blossom_num(0),
|
|
1626 |
|
|
1627 |
_blossom_index(0), _blossom_set(0), _blossom_data(0),
|
|
1628 |
_node_index(0), _node_heap_index(0), _node_data(0),
|
|
1629 |
_tree_set_index(0), _tree_set(0),
|
|
1630 |
|
|
1631 |
_delta1_index(0), _delta1(0),
|
|
1632 |
_delta2_index(0), _delta2(0),
|
|
1633 |
_delta3_index(0), _delta3(0),
|
|
1634 |
_delta4_index(0), _delta4(0),
|
|
1635 |
|
|
1636 |
_delta_sum() {}
|
|
1637 |
|
|
1638 |
~MaxWeightedMatching() {
|
|
1639 |
destroyStructures();
|
|
1640 |
}
|
|
1641 |
|
|
1642 |
/// \name Execution control
|
|
1643 |
/// The simplest way to execute the algorithm is to use the member
|
|
1644 |
/// \c run() member function.
|
|
1645 |
|
|
1646 |
///@{
|
|
1647 |
|
|
1648 |
/// \brief Initialize the algorithm
|
|
1649 |
///
|
|
1650 |
/// Initialize the algorithm
|
|
1651 |
void init() {
|
|
1652 |
createStructures();
|
|
1653 |
|
|
1654 |
for (ArcIt e(_graph); e != INVALID; ++e) {
|
|
1655 |
_node_heap_index->set(e, BinHeap<Value, ArcIntMap>::PRE_HEAP);
|
|
1656 |
}
|
|
1657 |
for (NodeIt n(_graph); n != INVALID; ++n) {
|
|
1658 |
_delta1_index->set(n, _delta1->PRE_HEAP);
|
|
1659 |
}
|
|
1660 |
for (EdgeIt e(_graph); e != INVALID; ++e) {
|
|
1661 |
_delta3_index->set(e, _delta3->PRE_HEAP);
|
|
1662 |
}
|
|
1663 |
for (int i = 0; i < _blossom_num; ++i) {
|
|
1664 |
_delta2_index->set(i, _delta2->PRE_HEAP);
|
|
1665 |
_delta4_index->set(i, _delta4->PRE_HEAP);
|
|
1666 |
}
|
|
1667 |
|
|
1668 |
int index = 0;
|
|
1669 |
for (NodeIt n(_graph); n != INVALID; ++n) {
|
|
1670 |
Value max = 0;
|
|
1671 |
for (OutArcIt e(_graph, n); e != INVALID; ++e) {
|
|
1672 |
if (_graph.target(e) == n) continue;
|
|
1673 |
if ((dualScale * _weight[e]) / 2 > max) {
|
|
1674 |
max = (dualScale * _weight[e]) / 2;
|
|
1675 |
}
|
|
1676 |
}
|
|
1677 |
_node_index->set(n, index);
|
|
1678 |
(*_node_data)[index].pot = max;
|
|
1679 |
_delta1->push(n, max);
|
|
1680 |
int blossom =
|
|
1681 |
_blossom_set->insert(n, std::numeric_limits<Value>::max());
|
|
1682 |
|
|
1683 |
_tree_set->insert(blossom);
|
|
1684 |
|
|
1685 |
(*_blossom_data)[blossom].status = EVEN;
|
|
1686 |
(*_blossom_data)[blossom].pred = INVALID;
|
|
1687 |
(*_blossom_data)[blossom].next = INVALID;
|
|
1688 |
(*_blossom_data)[blossom].pot = 0;
|
|
1689 |
(*_blossom_data)[blossom].offset = 0;
|
|
1690 |
++index;
|
|
1691 |
}
|
|
1692 |
for (EdgeIt e(_graph); e != INVALID; ++e) {
|
|
1693 |
int si = (*_node_index)[_graph.u(e)];
|
|
1694 |
int ti = (*_node_index)[_graph.v(e)];
|
|
1695 |
if (_graph.u(e) != _graph.v(e)) {
|
|
1696 |
_delta3->push(e, ((*_node_data)[si].pot + (*_node_data)[ti].pot -
|
|
1697 |
dualScale * _weight[e]) / 2);
|
|
1698 |
}
|
|
1699 |
}
|
|
1700 |
}
|
|
1701 |
|
|
1702 |
/// \brief Starts the algorithm
|
|
1703 |
///
|
|
1704 |
/// Starts the algorithm
|
|
1705 |
void start() {
|
|
1706 |
enum OpType {
|
|
1707 |
D1, D2, D3, D4
|
|
1708 |
};
|
|
1709 |
|
|
1710 |
int unmatched = _node_num;
|
|
1711 |
while (unmatched > 0) {
|
|
1712 |
Value d1 = !_delta1->empty() ?
|
|
1713 |
_delta1->prio() : std::numeric_limits<Value>::max();
|
|
1714 |
|
|
1715 |
Value d2 = !_delta2->empty() ?
|
|
1716 |
_delta2->prio() : std::numeric_limits<Value>::max();
|
|
1717 |
|
|
1718 |
Value d3 = !_delta3->empty() ?
|
|
1719 |
_delta3->prio() : std::numeric_limits<Value>::max();
|
|
1720 |
|
|
1721 |
Value d4 = !_delta4->empty() ?
|
|
1722 |
_delta4->prio() : std::numeric_limits<Value>::max();
|
|
1723 |
|
|
1724 |
_delta_sum = d1; OpType ot = D1;
|
|
1725 |
if (d2 < _delta_sum) { _delta_sum = d2; ot = D2; }
|
|
1726 |
if (d3 < _delta_sum) { _delta_sum = d3; ot = D3; }
|
|
1727 |
if (d4 < _delta_sum) { _delta_sum = d4; ot = D4; }
|
|
1728 |
|
|
1729 |
|
|
1730 |
switch (ot) {
|
|
1731 |
case D1:
|
|
1732 |
{
|
|
1733 |
Node n = _delta1->top();
|
|
1734 |
unmatchNode(n);
|
|
1735 |
--unmatched;
|
|
1736 |
}
|
|
1737 |
break;
|
|
1738 |
case D2:
|
|
1739 |
{
|
|
1740 |
int blossom = _delta2->top();
|
|
1741 |
Node n = _blossom_set->classTop(blossom);
|
|
1742 |
Arc e = (*_node_data)[(*_node_index)[n]].heap.top();
|
|
1743 |
extendOnArc(e);
|
|
1744 |
}
|
|
1745 |
break;
|
|
1746 |
case D3:
|
|
1747 |
{
|
|
1748 |
Edge e = _delta3->top();
|
|
1749 |
|
|
1750 |
int left_blossom = _blossom_set->find(_graph.u(e));
|
|
1751 |
int right_blossom = _blossom_set->find(_graph.v(e));
|
|
1752 |
|
|
1753 |
if (left_blossom == right_blossom) {
|
|
1754 |
_delta3->pop();
|
|
1755 |
} else {
|
|
1756 |
int left_tree;
|
|
1757 |
if ((*_blossom_data)[left_blossom].status == EVEN) {
|
|
1758 |
left_tree = _tree_set->find(left_blossom);
|
|
1759 |
} else {
|
|
1760 |
left_tree = -1;
|
|
1761 |
++unmatched;
|
|
1762 |
}
|
|
1763 |
int right_tree;
|
|
1764 |
if ((*_blossom_data)[right_blossom].status == EVEN) {
|
|
1765 |
right_tree = _tree_set->find(right_blossom);
|
|
1766 |
} else {
|
|
1767 |
right_tree = -1;
|
|
1768 |
++unmatched;
|
|
1769 |
}
|
|
1770 |
|
|
1771 |
if (left_tree == right_tree) {
|
|
1772 |
shrinkOnArc(e, left_tree);
|
|
1773 |
} else {
|
|
1774 |
augmentOnArc(e);
|
|
1775 |
unmatched -= 2;
|
|
1776 |
}
|
|
1777 |
}
|
|
1778 |
} break;
|
|
1779 |
case D4:
|
|
1780 |
splitBlossom(_delta4->top());
|
|
1781 |
break;
|
|
1782 |
}
|
|
1783 |
}
|
|
1784 |
extractMatching();
|
|
1785 |
}
|
|
1786 |
|
|
1787 |
/// \brief Runs %MaxWeightedMatching algorithm.
|
|
1788 |
///
|
|
1789 |
/// This method runs the %MaxWeightedMatching algorithm.
|
|
1790 |
///
|
|
1791 |
/// \note mwm.run() is just a shortcut of the following code.
|
|
1792 |
/// \code
|
|
1793 |
/// mwm.init();
|
|
1794 |
/// mwm.start();
|
|
1795 |
/// \endcode
|
|
1796 |
void run() {
|
|
1797 |
init();
|
|
1798 |
start();
|
|
1799 |
}
|
|
1800 |
|
|
1801 |
/// @}
|
|
1802 |
|
|
1803 |
/// \name Primal solution
|
|
1804 |
/// Functions for get the primal solution, ie. the matching.
|
|
1805 |
|
|
1806 |
/// @{
|
|
1807 |
|
|
1808 |
/// \brief Returns the matching value.
|
|
1809 |
///
|
|
1810 |
/// Returns the matching value.
|
|
1811 |
Value matchingValue() const {
|
|
1812 |
Value sum = 0;
|
|
1813 |
for (NodeIt n(_graph); n != INVALID; ++n) {
|
|
1814 |
if ((*_matching)[n] != INVALID) {
|
|
1815 |
sum += _weight[(*_matching)[n]];
|
|
1816 |
}
|
|
1817 |
}
|
|
1818 |
return sum /= 2;
|
|
1819 |
}
|
|
1820 |
|
|
1821 |
/// \brief Returns true when the arc is in the matching.
|
|
1822 |
///
|
|
1823 |
/// Returns true when the arc is in the matching.
|
|
1824 |
bool matching(const Edge& arc) const {
|
|
1825 |
return (*_matching)[_graph.u(arc)] == _graph.direct(arc, true);
|
|
1826 |
}
|
|
1827 |
|
|
1828 |
/// \brief Returns the incident matching arc.
|
|
1829 |
///
|
|
1830 |
/// Returns the incident matching arc from given node. If the
|
|
1831 |
/// node is not matched then it gives back \c INVALID.
|
|
1832 |
Arc matching(const Node& node) const {
|
|
1833 |
return (*_matching)[node];
|
|
1834 |
}
|
|
1835 |
|
|
1836 |
/// \brief Returns the mate of the node.
|
|
1837 |
///
|
|
1838 |
/// Returns the adjancent node in a mathcing arc. If the node is
|
|
1839 |
/// not matched then it gives back \c INVALID.
|
|
1840 |
Node mate(const Node& node) const {
|
|
1841 |
return (*_matching)[node] != INVALID ?
|
|
1842 |
_graph.target((*_matching)[node]) : INVALID;
|
|
1843 |
}
|
|
1844 |
|
|
1845 |
/// @}
|
|
1846 |
|
|
1847 |
/// \name Dual solution
|
|
1848 |
/// Functions for get the dual solution.
|
|
1849 |
|
|
1850 |
/// @{
|
|
1851 |
|
|
1852 |
/// \brief Returns the value of the dual solution.
|
|
1853 |
///
|
|
1854 |
/// Returns the value of the dual solution. It should be equal to
|
|
1855 |
/// the primal value scaled by \ref dualScale "dual scale".
|
|
1856 |
Value dualValue() const {
|
|
1857 |
Value sum = 0;
|
|
1858 |
for (NodeIt n(_graph); n != INVALID; ++n) {
|
|
1859 |
sum += nodeValue(n);
|
|
1860 |
}
|
|
1861 |
for (int i = 0; i < blossomNum(); ++i) {
|
|
1862 |
sum += blossomValue(i) * (blossomSize(i) / 2);
|
|
1863 |
}
|
|
1864 |
return sum;
|
|
1865 |
}
|
|
1866 |
|
|
1867 |
/// \brief Returns the value of the node.
|
|
1868 |
///
|
|
1869 |
/// Returns the the value of the node.
|
|
1870 |
Value nodeValue(const Node& n) const {
|
|
1871 |
return (*_node_potential)[n];
|
|
1872 |
}
|
|
1873 |
|
|
1874 |
/// \brief Returns the number of the blossoms in the basis.
|
|
1875 |
///
|
|
1876 |
/// Returns the number of the blossoms in the basis.
|
|
1877 |
/// \see BlossomIt
|
|
1878 |
int blossomNum() const {
|
|
1879 |
return _blossom_potential.size();
|
|
1880 |
}
|
|
1881 |
|
|
1882 |
|
|
1883 |
/// \brief Returns the number of the nodes in the blossom.
|
|
1884 |
///
|
|
1885 |
/// Returns the number of the nodes in the blossom.
|
|
1886 |
int blossomSize(int k) const {
|
|
1887 |
return _blossom_potential[k].end - _blossom_potential[k].begin;
|
|
1888 |
}
|
|
1889 |
|
|
1890 |
/// \brief Returns the value of the blossom.
|
|
1891 |
///
|
|
1892 |
/// Returns the the value of the blossom.
|
|
1893 |
/// \see BlossomIt
|
|
1894 |
Value blossomValue(int k) const {
|
|
1895 |
return _blossom_potential[k].value;
|
|
1896 |
}
|
|
1897 |
|
|
1898 |
/// \brief Lemon iterator for get the items of the blossom.
|
|
1899 |
///
|
|
1900 |
/// Lemon iterator for get the nodes of the blossom. This class
|
|
1901 |
/// provides a common style lemon iterator which gives back a
|
|
1902 |
/// subset of the nodes.
|
|
1903 |
class BlossomIt {
|
|
1904 |
public:
|
|
1905 |
|
|
1906 |
/// \brief Constructor.
|
|
1907 |
///
|
|
1908 |
/// Constructor for get the nodes of the variable.
|
|
1909 |
BlossomIt(const MaxWeightedMatching& algorithm, int variable)
|
|
1910 |
: _algorithm(&algorithm)
|
|
1911 |
{
|
|
1912 |
_index = _algorithm->_blossom_potential[variable].begin;
|
|
1913 |
_last = _algorithm->_blossom_potential[variable].end;
|
|
1914 |
}
|
|
1915 |
|
|
1916 |
/// \brief Invalid constructor.
|
|
1917 |
///
|
|
1918 |
/// Invalid constructor.
|
|
1919 |
BlossomIt(Invalid) : _index(-1) {}
|
|
1920 |
|
|
1921 |
/// \brief Conversion to node.
|
|
1922 |
///
|
|
1923 |
/// Conversion to node.
|
|
1924 |
operator Node() const {
|
|
1925 |
return _algorithm ? _algorithm->_blossom_node_list[_index] : INVALID;
|
|
1926 |
}
|
|
1927 |
|
|
1928 |
/// \brief Increment operator.
|
|
1929 |
///
|
|
1930 |
/// Increment operator.
|
|
1931 |
BlossomIt& operator++() {
|
|
1932 |
++_index;
|
|
1933 |
if (_index == _last) {
|
|
1934 |
_index = -1;
|
|
1935 |
}
|
|
1936 |
return *this;
|
|
1937 |
}
|
|
1938 |
|
|
1939 |
bool operator==(const BlossomIt& it) const {
|
|
1940 |
return _index == it._index;
|
|
1941 |
}
|
|
1942 |
bool operator!=(const BlossomIt& it) const {
|
|
1943 |
return _index != it._index;
|
|
1944 |
}
|
|
1945 |
|
|
1946 |
private:
|
|
1947 |
const MaxWeightedMatching* _algorithm;
|
|
1948 |
int _last;
|
|
1949 |
int _index;
|
|
1950 |
};
|
|
1951 |
|
|
1952 |
/// @}
|
|
1953 |
|
|
1954 |
};
|
|
1955 |
|
|
1956 |
/// \ingroup matching
|
|
1957 |
///
|
|
1958 |
/// \brief Weighted perfect matching in general graphs
|
|
1959 |
///
|
|
1960 |
/// This class provides an efficient implementation of Edmond's
|
|
1961 |
/// maximum weighted perfecr matching algorithm. The implementation
|
|
1962 |
/// is based on extensive use of priority queues and provides
|
|
1963 |
/// \f$O(nm\log(n))\f$ time complexity.
|
|
1964 |
///
|
|
1965 |
/// The maximum weighted matching problem is to find undirected
|
|
1966 |
/// arcs in the digraph with maximum overall weight and no two of
|
|
1967 |
/// them shares their endpoints and covers all nodes. The problem
|
|
1968 |
/// can be formulated with the next linear program:
|
|
1969 |
/// \f[ \sum_{e \in \delta(u)}x_e = 1 \quad \forall u\in V\f]
|
|
1970 |
///\f[ \sum_{e \in \gamma(B)}x_e \le \frac{\vert B \vert - 1}{2} \quad \forall B\in\mathcal{O}\f]
|
|
1971 |
/// \f[x_e \ge 0\quad \forall e\in E\f]
|
|
1972 |
/// \f[\max \sum_{e\in E}x_ew_e\f]
|
|
1973 |
/// where \f$\delta(X)\f$ is the set of arcs incident to a node in
|
|
1974 |
/// \f$X\f$, \f$\gamma(X)\f$ is the set of arcs with both endpoints in
|
|
1975 |
/// \f$X\f$ and \f$\mathcal{O}\f$ is the set of odd cardinality subsets of
|
|
1976 |
/// the nodes.
|
|
1977 |
///
|
|
1978 |
/// The algorithm calculates an optimal matching and a proof of the
|
|
1979 |
/// optimality. The solution of the dual problem can be used to check
|
|
1980 |
/// the result of the algorithm. The dual linear problem is the next:
|
|
1981 |
/// \f[ y_u + y_v + \sum_{B \in \mathcal{O}, uv \in \gamma(B)}z_B \ge w_{uv} \quad \forall uv\in E\f]
|
|
1982 |
/// \f[z_B \ge 0 \quad \forall B \in \mathcal{O}\f]
|
|
1983 |
/// \f[\min \sum_{u \in V}y_u + \sum_{B \in \mathcal{O}}\frac{\vert B \vert - 1}{2}z_B\f]
|
|
1984 |
///
|
|
1985 |
/// The algorithm can be executed with \c run() or the \c init() and
|
|
1986 |
/// then the \c start() member functions. After it the matching can
|
|
1987 |
/// be asked with \c matching() or mate() functions. The dual
|
|
1988 |
/// solution can be get with \c nodeValue(), \c blossomNum() and \c
|
|
1989 |
/// blossomValue() members and \ref MaxWeightedMatching::BlossomIt
|
|
1990 |
/// "BlossomIt" nested class which is able to iterate on the nodes
|
|
1991 |
/// of a blossom. If the value type is integral then the dual
|
|
1992 |
/// solution is multiplied by \ref MaxWeightedMatching::dualScale "4".
|
|
1993 |
template <typename _Graph,
|
|
1994 |
typename _WeightMap = typename _Graph::template EdgeMap<int> >
|
|
1995 |
class MaxWeightedPerfectMatching {
|
|
1996 |
public:
|
|
1997 |
|
|
1998 |
typedef _Graph Graph;
|
|
1999 |
typedef _WeightMap WeightMap;
|
|
2000 |
typedef typename WeightMap::Value Value;
|
|
2001 |
|
|
2002 |
/// \brief Scaling factor for dual solution
|
|
2003 |
///
|
|
2004 |
/// Scaling factor for dual solution, it is equal to 4 or 1
|
|
2005 |
/// according to the value type.
|
|
2006 |
static const int dualScale =
|
|
2007 |
std::numeric_limits<Value>::is_integer ? 4 : 1;
|
|
2008 |
|
|
2009 |
typedef typename Graph::template NodeMap<typename Graph::Arc>
|
|
2010 |
MatchingMap;
|
|
2011 |
|
|
2012 |
private:
|
|
2013 |
|
|
2014 |
TEMPLATE_GRAPH_TYPEDEFS(Graph);
|
|
2015 |
|
|
2016 |
typedef typename Graph::template NodeMap<Value> NodePotential;
|
|
2017 |
typedef std::vector<Node> BlossomNodeList;
|
|
2018 |
|
|
2019 |
struct BlossomVariable {
|
|
2020 |
int begin, end;
|
|
2021 |
Value value;
|
|
2022 |
|
|
2023 |
BlossomVariable(int _begin, int _end, Value _value)
|
|
2024 |
: begin(_begin), end(_end), value(_value) {}
|
|
2025 |
|
|
2026 |
};
|
|
2027 |
|
|
2028 |
typedef std::vector<BlossomVariable> BlossomPotential;
|
|
2029 |
|
|
2030 |
const Graph& _graph;
|
|
2031 |
const WeightMap& _weight;
|
|
2032 |
|
|
2033 |
MatchingMap* _matching;
|
|
2034 |
|
|
2035 |
NodePotential* _node_potential;
|
|
2036 |
|
|
2037 |
BlossomPotential _blossom_potential;
|
|
2038 |
BlossomNodeList _blossom_node_list;
|
|
2039 |
|
|
2040 |
int _node_num;
|
|
2041 |
int _blossom_num;
|
|
2042 |
|
|
2043 |
typedef typename Graph::template NodeMap<int> NodeIntMap;
|
|
2044 |
typedef typename Graph::template ArcMap<int> ArcIntMap;
|
|
2045 |
typedef typename Graph::template EdgeMap<int> EdgeIntMap;
|
|
2046 |
typedef RangeMap<int> IntIntMap;
|
|
2047 |
|
|
2048 |
enum Status {
|
|
2049 |
EVEN = -1, MATCHED = 0, ODD = 1
|
|
2050 |
};
|
|
2051 |
|
|
2052 |
typedef HeapUnionFind<Value, NodeIntMap> BlossomSet;
|
|
2053 |
struct BlossomData {
|
|
2054 |
int tree;
|
|
2055 |
Status status;
|
|
2056 |
Arc pred, next;
|
|
2057 |
Value pot, offset;
|
|
2058 |
};
|
|
2059 |
|
|
2060 |
NodeIntMap *_blossom_index;
|
|
2061 |
BlossomSet *_blossom_set;
|
|
2062 |
RangeMap<BlossomData>* _blossom_data;
|
|
2063 |
|
|
2064 |
NodeIntMap *_node_index;
|
|
2065 |
ArcIntMap *_node_heap_index;
|
|
2066 |
|
|
2067 |
struct NodeData {
|
|
2068 |
|
|
2069 |
NodeData(ArcIntMap& node_heap_index)
|
|
2070 |
: heap(node_heap_index) {}
|
|
2071 |
|
|
2072 |
int blossom;
|
|
2073 |
Value pot;
|
|
2074 |
BinHeap<Value, ArcIntMap> heap;
|
|
2075 |
std::map<int, Arc> heap_index;
|
|
2076 |
|
|
2077 |
int tree;
|
|
2078 |
};
|
|
2079 |
|
|
2080 |
RangeMap<NodeData>* _node_data;
|
|
2081 |
|
|
2082 |
typedef ExtendFindEnum<IntIntMap> TreeSet;
|
|
2083 |
|
|
2084 |
IntIntMap *_tree_set_index;
|
|
2085 |
TreeSet *_tree_set;
|
|
2086 |
|
|
2087 |
IntIntMap *_delta2_index;
|
|
2088 |
BinHeap<Value, IntIntMap> *_delta2;
|
|
2089 |
|
|
2090 |
EdgeIntMap *_delta3_index;
|
|
2091 |
BinHeap<Value, EdgeIntMap> *_delta3;
|
|
2092 |
|
|
2093 |
IntIntMap *_delta4_index;
|
|
2094 |
BinHeap<Value, IntIntMap> *_delta4;
|
|
2095 |
|
|
2096 |
Value _delta_sum;
|
|
2097 |
|
|
2098 |
void createStructures() {
|
|
2099 |
_node_num = countNodes(_graph);
|
|
2100 |
_blossom_num = _node_num * 3 / 2;
|
|
2101 |
|
|
2102 |
if (!_matching) {
|
|
2103 |
_matching = new MatchingMap(_graph);
|
|
2104 |
}
|
|
2105 |
if (!_node_potential) {
|
|
2106 |
_node_potential = new NodePotential(_graph);
|
|
2107 |
}
|
|
2108 |
if (!_blossom_set) {
|
|
2109 |
_blossom_index = new NodeIntMap(_graph);
|
|
2110 |
_blossom_set = new BlossomSet(*_blossom_index);
|
|
2111 |
_blossom_data = new RangeMap<BlossomData>(_blossom_num);
|
|
2112 |
}
|
|
2113 |
|
|
2114 |
if (!_node_index) {
|
|
2115 |
_node_index = new NodeIntMap(_graph);
|
|
2116 |
_node_heap_index = new ArcIntMap(_graph);
|
|
2117 |
_node_data = new RangeMap<NodeData>(_node_num,
|
|
2118 |
NodeData(*_node_heap_index));
|
|
2119 |
}
|
|
2120 |
|
|
2121 |
if (!_tree_set) {
|
|
2122 |
_tree_set_index = new IntIntMap(_blossom_num);
|
|
2123 |
_tree_set = new TreeSet(*_tree_set_index);
|
|
2124 |
}
|
|
2125 |
if (!_delta2) {
|
|
2126 |
_delta2_index = new IntIntMap(_blossom_num);
|
|
2127 |
_delta2 = new BinHeap<Value, IntIntMap>(*_delta2_index);
|
|
2128 |
}
|
|
2129 |
if (!_delta3) {
|
|
2130 |
_delta3_index = new EdgeIntMap(_graph);
|
|
2131 |
_delta3 = new BinHeap<Value, EdgeIntMap>(*_delta3_index);
|
|
2132 |
}
|
|
2133 |
if (!_delta4) {
|
|
2134 |
_delta4_index = new IntIntMap(_blossom_num);
|
|
2135 |
_delta4 = new BinHeap<Value, IntIntMap>(*_delta4_index);
|
|
2136 |
}
|
|
2137 |
}
|
|
2138 |
|
|
2139 |
void destroyStructures() {
|
|
2140 |
_node_num = countNodes(_graph);
|
|
2141 |
_blossom_num = _node_num * 3 / 2;
|
|
2142 |
|
|
2143 |
if (_matching) {
|
|
2144 |
delete _matching;
|
|
2145 |
}
|
|
2146 |
if (_node_potential) {
|
|
2147 |
delete _node_potential;
|
|
2148 |
}
|
|
2149 |
if (_blossom_set) {
|
|
2150 |
delete _blossom_index;
|
|
2151 |
delete _blossom_set;
|
|
2152 |
delete _blossom_data;
|
|
2153 |
}
|
|
2154 |
|
|
2155 |
if (_node_index) {
|
|
2156 |
delete _node_index;
|
|
2157 |
delete _node_heap_index;
|
|
2158 |
delete _node_data;
|
|
2159 |
}
|
|
2160 |
|
|
2161 |
if (_tree_set) {
|
|
2162 |
delete _tree_set_index;
|
|
2163 |
delete _tree_set;
|
|
2164 |
}
|
|
2165 |
if (_delta2) {
|
|
2166 |
delete _delta2_index;
|
|
2167 |
delete _delta2;
|
|
2168 |
}
|
|
2169 |
if (_delta3) {
|
|
2170 |
delete _delta3_index;
|
|
2171 |
delete _delta3;
|
|
2172 |
}
|
|
2173 |
if (_delta4) {
|
|
2174 |
delete _delta4_index;
|
|
2175 |
delete _delta4;
|
|
2176 |
}
|
|
2177 |
}
|
|
2178 |
|
|
2179 |
void matchedToEven(int blossom, int tree) {
|
|
2180 |
if (_delta2->state(blossom) == _delta2->IN_HEAP) {
|
|
2181 |
_delta2->erase(blossom);
|
|
2182 |
}
|
|
2183 |
|
|
2184 |
if (!_blossom_set->trivial(blossom)) {
|
|
2185 |
(*_blossom_data)[blossom].pot -=
|
|
2186 |
2 * (_delta_sum - (*_blossom_data)[blossom].offset);
|
|
2187 |
}
|
|
2188 |
|
|
2189 |
for (typename BlossomSet::ItemIt n(*_blossom_set, blossom);
|
|
2190 |
n != INVALID; ++n) {
|
|
2191 |
|
|
2192 |
_blossom_set->increase(n, std::numeric_limits<Value>::max());
|
|
2193 |
int ni = (*_node_index)[n];
|
|
2194 |
|
|
2195 |
(*_node_data)[ni].heap.clear();
|
|
2196 |
(*_node_data)[ni].heap_index.clear();
|
|
2197 |
|
|
2198 |
(*_node_data)[ni].pot += _delta_sum - (*_blossom_data)[blossom].offset;
|
|
2199 |
|
|
2200 |
for (InArcIt e(_graph, n); e != INVALID; ++e) {
|
|
2201 |
Node v = _graph.source(e);
|
|
2202 |
int vb = _blossom_set->find(v);
|
|
2203 |
int vi = (*_node_index)[v];
|
|
2204 |
|
|
2205 |
Value rw = (*_node_data)[ni].pot + (*_node_data)[vi].pot -
|
|
2206 |
dualScale * _weight[e];
|
|
2207 |
|
|
2208 |
if ((*_blossom_data)[vb].status == EVEN) {
|
|
2209 |
if (_delta3->state(e) != _delta3->IN_HEAP && blossom != vb) {
|
|
2210 |
_delta3->push(e, rw / 2);
|
|
2211 |
}
|
|
2212 |
} else {
|
|
2213 |
typename std::map<int, Arc>::iterator it =
|
|
2214 |
(*_node_data)[vi].heap_index.find(tree);
|
|
2215 |
|
|
2216 |
if (it != (*_node_data)[vi].heap_index.end()) {
|
|
2217 |
if ((*_node_data)[vi].heap[it->second] > rw) {
|
|
2218 |
(*_node_data)[vi].heap.replace(it->second, e);
|
|
2219 |
(*_node_data)[vi].heap.decrease(e, rw);
|
|
2220 |
it->second = e;
|
|
2221 |
}
|
|
2222 |
} else {
|
|
2223 |
(*_node_data)[vi].heap.push(e, rw);
|
|
2224 |
(*_node_data)[vi].heap_index.insert(std::make_pair(tree, e));
|
|
2225 |
}
|
|
2226 |
|
|
2227 |
if ((*_blossom_set)[v] > (*_node_data)[vi].heap.prio()) {
|
|
2228 |
_blossom_set->decrease(v, (*_node_data)[vi].heap.prio());
|
|
2229 |
|
|
2230 |
if ((*_blossom_data)[vb].status == MATCHED) {
|
|
2231 |
if (_delta2->state(vb) != _delta2->IN_HEAP) {
|
|
2232 |
_delta2->push(vb, _blossom_set->classPrio(vb) -
|
|
2233 |
(*_blossom_data)[vb].offset);
|
|
2234 |
} else if ((*_delta2)[vb] > _blossom_set->classPrio(vb) -
|
|
2235 |
(*_blossom_data)[vb].offset){
|
|
2236 |
_delta2->decrease(vb, _blossom_set->classPrio(vb) -
|
|
2237 |
(*_blossom_data)[vb].offset);
|
|
2238 |
}
|
|
2239 |
}
|
|
2240 |
}
|
|
2241 |
}
|
|
2242 |
}
|
|
2243 |
}
|
|
2244 |
(*_blossom_data)[blossom].offset = 0;
|
|
2245 |
}
|
|
2246 |
|
|
2247 |
void matchedToOdd(int blossom) {
|
|
2248 |
if (_delta2->state(blossom) == _delta2->IN_HEAP) {
|
|
2249 |
_delta2->erase(blossom);
|
|
2250 |
}
|
|
2251 |
(*_blossom_data)[blossom].offset += _delta_sum;
|
|
2252 |
if (!_blossom_set->trivial(blossom)) {
|
|
2253 |
_delta4->push(blossom, (*_blossom_data)[blossom].pot / 2 +
|
|
2254 |
(*_blossom_data)[blossom].offset);
|
|
2255 |
}
|
|
2256 |
}
|
|
2257 |
|
|
2258 |
void evenToMatched(int blossom, int tree) {
|
|
2259 |
if (!_blossom_set->trivial(blossom)) {
|
|
2260 |
(*_blossom_data)[blossom].pot += 2 * _delta_sum;
|
|
2261 |
}
|
|
2262 |
|
|
2263 |
for (typename BlossomSet::ItemIt n(*_blossom_set, blossom);
|
|
2264 |
n != INVALID; ++n) {
|
|
2265 |
int ni = (*_node_index)[n];
|
|
2266 |
(*_node_data)[ni].pot -= _delta_sum;
|
|
2267 |
|
|
2268 |
for (InArcIt e(_graph, n); e != INVALID; ++e) {
|
|
2269 |
Node v = _graph.source(e);
|
|
2270 |
int vb = _blossom_set->find(v);
|
|
2271 |
int vi = (*_node_index)[v];
|
|
2272 |
|
|
2273 |
Value rw = (*_node_data)[ni].pot + (*_node_data)[vi].pot -
|
|
2274 |
dualScale * _weight[e];
|
|
2275 |
|
|
2276 |
if (vb == blossom) {
|
|
2277 |
if (_delta3->state(e) == _delta3->IN_HEAP) {
|
|
2278 |
_delta3->erase(e);
|
|
2279 |
}
|
|
2280 |
} else if ((*_blossom_data)[vb].status == EVEN) {
|
|
2281 |
|
|
2282 |
if (_delta3->state(e) == _delta3->IN_HEAP) {
|
|
2283 |
_delta3->erase(e);
|
|
2284 |
}
|
|
2285 |
|
|
2286 |
int vt = _tree_set->find(vb);
|
|
2287 |
|
|
2288 |
if (vt != tree) {
|
|
2289 |
|
|
2290 |
Arc r = _graph.oppositeArc(e);
|
|
2291 |
|
|
2292 |
typename std::map<int, Arc>::iterator it =
|
|
2293 |
(*_node_data)[ni].heap_index.find(vt);
|
|
2294 |
|
|
2295 |
if (it != (*_node_data)[ni].heap_index.end()) {
|
|
2296 |
if ((*_node_data)[ni].heap[it->second] > rw) {
|
|
2297 |
(*_node_data)[ni].heap.replace(it->second, r);
|
|
2298 |
(*_node_data)[ni].heap.decrease(r, rw);
|
|
2299 |
it->second = r;
|
|
2300 |
}
|
|
2301 |
} else {
|
|
2302 |
(*_node_data)[ni].heap.push(r, rw);
|
|
2303 |
(*_node_data)[ni].heap_index.insert(std::make_pair(vt, r));
|
|
2304 |
}
|
|
2305 |
|
|
2306 |
if ((*_blossom_set)[n] > (*_node_data)[ni].heap.prio()) {
|
|
2307 |
_blossom_set->decrease(n, (*_node_data)[ni].heap.prio());
|
|
2308 |
|
|
2309 |
if (_delta2->state(blossom) != _delta2->IN_HEAP) {
|
|
2310 |
_delta2->push(blossom, _blossom_set->classPrio(blossom) -
|
|
2311 |
(*_blossom_data)[blossom].offset);
|
|
2312 |
} else if ((*_delta2)[blossom] >
|
|
2313 |
_blossom_set->classPrio(blossom) -
|
|
2314 |
(*_blossom_data)[blossom].offset){
|
|
2315 |
_delta2->decrease(blossom, _blossom_set->classPrio(blossom) -
|
|
2316 |
(*_blossom_data)[blossom].offset);
|
|
2317 |
}
|
|
2318 |
}
|
|
2319 |
}
|
|
2320 |
} else {
|
|
2321 |
|
|
2322 |
typename std::map<int, Arc>::iterator it =
|
|
2323 |
(*_node_data)[vi].heap_index.find(tree);
|
|
2324 |
|
|
2325 |
if (it != (*_node_data)[vi].heap_index.end()) {
|
|
2326 |
(*_node_data)[vi].heap.erase(it->second);
|
|
2327 |
(*_node_data)[vi].heap_index.erase(it);
|
|
2328 |
if ((*_node_data)[vi].heap.empty()) {
|
|
2329 |
_blossom_set->increase(v, std::numeric_limits<Value>::max());
|
|
2330 |
} else if ((*_blossom_set)[v] < (*_node_data)[vi].heap.prio()) {
|
|
2331 |
_blossom_set->increase(v, (*_node_data)[vi].heap.prio());
|
|
2332 |
}
|
|
2333 |
|
|
2334 |
if ((*_blossom_data)[vb].status == MATCHED) {
|
|
2335 |
if (_blossom_set->classPrio(vb) ==
|
|
2336 |
std::numeric_limits<Value>::max()) {
|
|
2337 |
_delta2->erase(vb);
|
|
2338 |
} else if ((*_delta2)[vb] < _blossom_set->classPrio(vb) -
|
|
2339 |
(*_blossom_data)[vb].offset) {
|
|
2340 |
_delta2->increase(vb, _blossom_set->classPrio(vb) -
|
|
2341 |
(*_blossom_data)[vb].offset);
|
|
2342 |
}
|
|
2343 |
}
|
|
2344 |
}
|
|
2345 |
}
|
|
2346 |
}
|
|
2347 |
}
|
|
2348 |
}
|
|
2349 |
|
|
2350 |
void oddToMatched(int blossom) {
|
|
2351 |
(*_blossom_data)[blossom].offset -= _delta_sum;
|
|
2352 |
|
|
2353 |
if (_blossom_set->classPrio(blossom) !=
|
|
2354 |
std::numeric_limits<Value>::max()) {
|
|
2355 |
_delta2->push(blossom, _blossom_set->classPrio(blossom) -
|
|
2356 |
(*_blossom_data)[blossom].offset);
|
|
2357 |
}
|
|
2358 |
|
|
2359 |
if (!_blossom_set->trivial(blossom)) {
|
|
2360 |
_delta4->erase(blossom);
|
|
2361 |
}
|
|
2362 |
}
|
|
2363 |
|
|
2364 |
void oddToEven(int blossom, int tree) {
|
|
2365 |
if (!_blossom_set->trivial(blossom)) {
|
|
2366 |
_delta4->erase(blossom);
|
|
2367 |
(*_blossom_data)[blossom].pot -=
|
|
2368 |
2 * (2 * _delta_sum - (*_blossom_data)[blossom].offset);
|
|
2369 |
}
|
|
2370 |
|
|
2371 |
for (typename BlossomSet::ItemIt n(*_blossom_set, blossom);
|
|
2372 |
n != INVALID; ++n) {
|
|
2373 |
int ni = (*_node_index)[n];
|
|
2374 |
|
|
2375 |
_blossom_set->increase(n, std::numeric_limits<Value>::max());
|
|
2376 |
|
|
2377 |
(*_node_data)[ni].heap.clear();
|
|
2378 |
(*_node_data)[ni].heap_index.clear();
|
|
2379 |
(*_node_data)[ni].pot +=
|
|
2380 |
2 * _delta_sum - (*_blossom_data)[blossom].offset;
|
|
2381 |
|
|
2382 |
for (InArcIt e(_graph, n); e != INVALID; ++e) {
|
|
2383 |
Node v = _graph.source(e);
|
|
2384 |
int vb = _blossom_set->find(v);
|
|
2385 |
int vi = (*_node_index)[v];
|
|
2386 |
|
|
2387 |
Value rw = (*_node_data)[ni].pot + (*_node_data)[vi].pot -
|
|
2388 |
dualScale * _weight[e];
|
|
2389 |
|
|
2390 |
if ((*_blossom_data)[vb].status == EVEN) {
|
|
2391 |
if (_delta3->state(e) != _delta3->IN_HEAP && blossom != vb) {
|
|
2392 |
_delta3->push(e, rw / 2);
|
|
2393 |
}
|
|
2394 |
} else {
|
|
2395 |
|
|
2396 |
typename std::map<int, Arc>::iterator it =
|
|
2397 |
(*_node_data)[vi].heap_index.find(tree);
|
|
2398 |
|
|
2399 |
if (it != (*_node_data)[vi].heap_index.end()) {
|
|
2400 |
if ((*_node_data)[vi].heap[it->second] > rw) {
|
|
2401 |
(*_node_data)[vi].heap.replace(it->second, e);
|
|
2402 |
(*_node_data)[vi].heap.decrease(e, rw);
|
|
2403 |
it->second = e;
|
|
2404 |
}
|
|
2405 |
} else {
|
|
2406 |
(*_node_data)[vi].heap.push(e, rw);
|
|
2407 |
(*_node_data)[vi].heap_index.insert(std::make_pair(tree, e));
|
|
2408 |
}
|
|
2409 |
|
|
2410 |
if ((*_blossom_set)[v] > (*_node_data)[vi].heap.prio()) {
|
|
2411 |
_blossom_set->decrease(v, (*_node_data)[vi].heap.prio());
|
|
2412 |
|
|
2413 |
if ((*_blossom_data)[vb].status == MATCHED) {
|
|
2414 |
if (_delta2->state(vb) != _delta2->IN_HEAP) {
|
|
2415 |
_delta2->push(vb, _blossom_set->classPrio(vb) -
|
|
2416 |
(*_blossom_data)[vb].offset);
|
|
2417 |
} else if ((*_delta2)[vb] > _blossom_set->classPrio(vb) -
|
|
2418 |
(*_blossom_data)[vb].offset) {
|
|
2419 |
_delta2->decrease(vb, _blossom_set->classPrio(vb) -
|
|
2420 |
(*_blossom_data)[vb].offset);
|
|
2421 |
}
|
|
2422 |
}
|
|
2423 |
}
|
|
2424 |
}
|
|
2425 |
}
|
|
2426 |
}
|
|
2427 |
(*_blossom_data)[blossom].offset = 0;
|
|
2428 |
}
|
|
2429 |
|
|
2430 |
void alternatePath(int even, int tree) {
|
|
2431 |
int odd;
|
|
2432 |
|
|
2433 |
evenToMatched(even, tree);
|
|
2434 |
(*_blossom_data)[even].status = MATCHED;
|
|
2435 |
|
|
2436 |
while ((*_blossom_data)[even].pred != INVALID) {
|
|
2437 |
odd = _blossom_set->find(_graph.target((*_blossom_data)[even].pred));
|
|
2438 |
(*_blossom_data)[odd].status = MATCHED;
|
|
2439 |
oddToMatched(odd);
|
|
2440 |
(*_blossom_data)[odd].next = (*_blossom_data)[odd].pred;
|
|
2441 |
|
|
2442 |
even = _blossom_set->find(_graph.target((*_blossom_data)[odd].pred));
|
|
2443 |
(*_blossom_data)[even].status = MATCHED;
|
|
2444 |
evenToMatched(even, tree);
|
|
2445 |
(*_blossom_data)[even].next =
|
|
2446 |
_graph.oppositeArc((*_blossom_data)[odd].pred);
|
|
2447 |
}
|
|
2448 |
|
|
2449 |
}
|
|
2450 |
|
|
2451 |
void destroyTree(int tree) {
|
|
2452 |
for (TreeSet::ItemIt b(*_tree_set, tree); b != INVALID; ++b) {
|
|
2453 |
if ((*_blossom_data)[b].status == EVEN) {
|
|
2454 |
(*_blossom_data)[b].status = MATCHED;
|
|
2455 |
evenToMatched(b, tree);
|
|
2456 |
} else if ((*_blossom_data)[b].status == ODD) {
|
|
2457 |
(*_blossom_data)[b].status = MATCHED;
|
|
2458 |
oddToMatched(b);
|
|
2459 |
}
|
|
2460 |
}
|
|
2461 |
_tree_set->eraseClass(tree);
|
|
2462 |
}
|
|
2463 |
|
|
2464 |
void augmentOnArc(const Edge& arc) {
|
|
2465 |
|
|
2466 |
int left = _blossom_set->find(_graph.u(arc));
|
|
2467 |
int right = _blossom_set->find(_graph.v(arc));
|
|
2468 |
|
|
2469 |
int left_tree = _tree_set->find(left);
|
|
2470 |
alternatePath(left, left_tree);
|
|
2471 |
destroyTree(left_tree);
|
|
2472 |
|
|
2473 |
int right_tree = _tree_set->find(right);
|
|
2474 |
alternatePath(right, right_tree);
|
|
2475 |
destroyTree(right_tree);
|
|
2476 |
|
|
2477 |
(*_blossom_data)[left].next = _graph.direct(arc, true);
|
|
2478 |
(*_blossom_data)[right].next = _graph.direct(arc, false);
|
|
2479 |
}
|
|
2480 |
|
|
2481 |
void extendOnArc(const Arc& arc) {
|
|
2482 |
int base = _blossom_set->find(_graph.target(arc));
|
|
2483 |
int tree = _tree_set->find(base);
|
|
2484 |
|
|
2485 |
int odd = _blossom_set->find(_graph.source(arc));
|
|
2486 |
_tree_set->insert(odd, tree);
|
|
2487 |
(*_blossom_data)[odd].status = ODD;
|
|
2488 |
matchedToOdd(odd);
|
|
2489 |
(*_blossom_data)[odd].pred = arc;
|
|
2490 |
|
|
2491 |
int even = _blossom_set->find(_graph.target((*_blossom_data)[odd].next));
|
|
2492 |
(*_blossom_data)[even].pred = (*_blossom_data)[even].next;
|
|
2493 |
_tree_set->insert(even, tree);
|
|
2494 |
(*_blossom_data)[even].status = EVEN;
|
|
2495 |
matchedToEven(even, tree);
|
|
2496 |
}
|
|
2497 |
|
|
2498 |
void shrinkOnArc(const Edge& edge, int tree) {
|
|
2499 |
int nca = -1;
|
|
2500 |
std::vector<int> left_path, right_path;
|
|
2501 |
|
|
2502 |
{
|
|
2503 |
std::set<int> left_set, right_set;
|
|
2504 |
int left = _blossom_set->find(_graph.u(edge));
|
|
2505 |
left_path.push_back(left);
|
|
2506 |
left_set.insert(left);
|
|
2507 |
|
|
2508 |
int right = _blossom_set->find(_graph.v(edge));
|
|
2509 |
right_path.push_back(right);
|
|
2510 |
right_set.insert(right);
|
|
2511 |
|
|
2512 |
while (true) {
|
|
2513 |
|
|
2514 |
if ((*_blossom_data)[left].pred == INVALID) break;
|
|
2515 |
|
|
2516 |
left =
|
|
2517 |
_blossom_set->find(_graph.target((*_blossom_data)[left].pred));
|
|
2518 |
left_path.push_back(left);
|
|
2519 |
left =
|
|
2520 |
_blossom_set->find(_graph.target((*_blossom_data)[left].pred));
|
|
2521 |
left_path.push_back(left);
|
|
2522 |
|
|
2523 |
left_set.insert(left);
|
|
2524 |
|
|
2525 |
if (right_set.find(left) != right_set.end()) {
|
|
2526 |
nca = left;
|
|
2527 |
break;
|
|
2528 |
}
|
|
2529 |
|
|
2530 |
if ((*_blossom_data)[right].pred == INVALID) break;
|
|
2531 |
|
|
2532 |
right =
|
|
2533 |
_blossom_set->find(_graph.target((*_blossom_data)[right].pred));
|
|
2534 |
right_path.push_back(right);
|
|
2535 |
right =
|
|
2536 |
_blossom_set->find(_graph.target((*_blossom_data)[right].pred));
|
|
2537 |
right_path.push_back(right);
|
|
2538 |
|
|
2539 |
right_set.insert(right);
|
|
2540 |
|
|
2541 |
if (left_set.find(right) != left_set.end()) {
|
|
2542 |
nca = right;
|
|
2543 |
break;
|
|
2544 |
}
|
|
2545 |
|
|
2546 |
}
|
|
2547 |
|
|
2548 |
if (nca == -1) {
|
|
2549 |
if ((*_blossom_data)[left].pred == INVALID) {
|
|
2550 |
nca = right;
|
|
2551 |
while (left_set.find(nca) == left_set.end()) {
|
|
2552 |
nca =
|
|
2553 |
_blossom_set->find(_graph.target((*_blossom_data)[nca].pred));
|
|
2554 |
right_path.push_back(nca);
|
|
2555 |
nca =
|
|
2556 |
_blossom_set->find(_graph.target((*_blossom_data)[nca].pred));
|
|
2557 |
right_path.push_back(nca);
|
|
2558 |
}
|
|
2559 |
} else {
|
|
2560 |
nca = left;
|
|
2561 |
while (right_set.find(nca) == right_set.end()) {
|
|
2562 |
nca =
|
|
2563 |
_blossom_set->find(_graph.target((*_blossom_data)[nca].pred));
|
|
2564 |
left_path.push_back(nca);
|
|
2565 |
nca =
|
|
2566 |
_blossom_set->find(_graph.target((*_blossom_data)[nca].pred));
|
|
2567 |
left_path.push_back(nca);
|
|
2568 |
}
|
|
2569 |
}
|
|
2570 |
}
|
|
2571 |
}
|
|
2572 |
|
|
2573 |
std::vector<int> subblossoms;
|
|
2574 |
Arc prev;
|
|
2575 |
|
|
2576 |
prev = _graph.direct(edge, true);
|
|
2577 |
for (int i = 0; left_path[i] != nca; i += 2) {
|
|
2578 |
subblossoms.push_back(left_path[i]);
|
|
2579 |
(*_blossom_data)[left_path[i]].next = prev;
|
|
2580 |
_tree_set->erase(left_path[i]);
|
|
2581 |
|
|
2582 |
subblossoms.push_back(left_path[i + 1]);
|
|
2583 |
(*_blossom_data)[left_path[i + 1]].status = EVEN;
|
|
2584 |
oddToEven(left_path[i + 1], tree);
|
|
2585 |
_tree_set->erase(left_path[i + 1]);
|
|
2586 |
prev = _graph.oppositeArc((*_blossom_data)[left_path[i + 1]].pred);
|
|
2587 |
}
|
|
2588 |
|
|
2589 |
int k = 0;
|
|
2590 |
while (right_path[k] != nca) ++k;
|
|
2591 |
|
|
2592 |
subblossoms.push_back(nca);
|
|
2593 |
(*_blossom_data)[nca].next = prev;
|
|
2594 |
|
|
2595 |
for (int i = k - 2; i >= 0; i -= 2) {
|
|
2596 |
subblossoms.push_back(right_path[i + 1]);
|
|
2597 |
(*_blossom_data)[right_path[i + 1]].status = EVEN;
|
|
2598 |
oddToEven(right_path[i + 1], tree);
|
|
2599 |
_tree_set->erase(right_path[i + 1]);
|
|
2600 |
|
|
2601 |
(*_blossom_data)[right_path[i + 1]].next =
|
|
2602 |
(*_blossom_data)[right_path[i + 1]].pred;
|
|
2603 |
|
|
2604 |
subblossoms.push_back(right_path[i]);
|
|
2605 |
_tree_set->erase(right_path[i]);
|
|
2606 |
}
|
|
2607 |
|
|
2608 |
int surface =
|
|
2609 |
_blossom_set->join(subblossoms.begin(), subblossoms.end());
|
|
2610 |
|
|
2611 |
for (int i = 0; i < int(subblossoms.size()); ++i) {
|
|
2612 |
if (!_blossom_set->trivial(subblossoms[i])) {
|
|
2613 |
(*_blossom_data)[subblossoms[i]].pot += 2 * _delta_sum;
|
|
2614 |
}
|
|
2615 |
(*_blossom_data)[subblossoms[i]].status = MATCHED;
|
|
2616 |
}
|
|
2617 |
|
|
2618 |
(*_blossom_data)[surface].pot = -2 * _delta_sum;
|
|
2619 |
(*_blossom_data)[surface].offset = 0;
|
|
2620 |
(*_blossom_data)[surface].status = EVEN;
|
|
2621 |
(*_blossom_data)[surface].pred = (*_blossom_data)[nca].pred;
|
|
2622 |
(*_blossom_data)[surface].next = (*_blossom_data)[nca].pred;
|
|
2623 |
|
|
2624 |
_tree_set->insert(surface, tree);
|
|
2625 |
_tree_set->erase(nca);
|
|
2626 |
}
|
|
2627 |
|
|
2628 |
void splitBlossom(int blossom) {
|
|
2629 |
Arc next = (*_blossom_data)[blossom].next;
|
|
2630 |
Arc pred = (*_blossom_data)[blossom].pred;
|
|
2631 |
|
|
2632 |
int tree = _tree_set->find(blossom);
|
|
2633 |
|
|
2634 |
(*_blossom_data)[blossom].status = MATCHED;
|
|
2635 |
oddToMatched(blossom);
|
|
2636 |
if (_delta2->state(blossom) == _delta2->IN_HEAP) {
|
|
2637 |
_delta2->erase(blossom);
|
|
2638 |
}
|
|
2639 |
|
|
2640 |
std::vector<int> subblossoms;
|
|
2641 |
_blossom_set->split(blossom, std::back_inserter(subblossoms));
|
|
2642 |
|
|
2643 |
Value offset = (*_blossom_data)[blossom].offset;
|
|
2644 |
int b = _blossom_set->find(_graph.source(pred));
|
|
2645 |
int d = _blossom_set->find(_graph.source(next));
|
|
2646 |
|
|
2647 |
int ib = -1, id = -1;
|
|
2648 |
for (int i = 0; i < int(subblossoms.size()); ++i) {
|
|
2649 |
if (subblossoms[i] == b) ib = i;
|
|
2650 |
if (subblossoms[i] == d) id = i;
|
|
2651 |
|
|
2652 |
(*_blossom_data)[subblossoms[i]].offset = offset;
|
|
2653 |
if (!_blossom_set->trivial(subblossoms[i])) {
|
|
2654 |
(*_blossom_data)[subblossoms[i]].pot -= 2 * offset;
|
|
2655 |
}
|
|
2656 |
if (_blossom_set->classPrio(subblossoms[i]) !=
|
|
2657 |
std::numeric_limits<Value>::max()) {
|
|
2658 |
_delta2->push(subblossoms[i],
|
|
2659 |
_blossom_set->classPrio(subblossoms[i]) -
|
|
2660 |
(*_blossom_data)[subblossoms[i]].offset);
|
|
2661 |
}
|
|
2662 |
}
|
|
2663 |
|
|
2664 |
if (id > ib ? ((id - ib) % 2 == 0) : ((ib - id) % 2 == 1)) {
|
|
2665 |
for (int i = (id + 1) % subblossoms.size();
|
|
2666 |
i != ib; i = (i + 2) % subblossoms.size()) {
|
|
2667 |
int sb = subblossoms[i];
|
|
2668 |
int tb = subblossoms[(i + 1) % subblossoms.size()];
|
|
2669 |
(*_blossom_data)[sb].next =
|
|
2670 |
_graph.oppositeArc((*_blossom_data)[tb].next);
|
|
2671 |
}
|
|
2672 |
|
|
2673 |
for (int i = ib; i != id; i = (i + 2) % subblossoms.size()) {
|
|
2674 |
int sb = subblossoms[i];
|
|
2675 |
int tb = subblossoms[(i + 1) % subblossoms.size()];
|
|
2676 |
int ub = subblossoms[(i + 2) % subblossoms.size()];
|
|
2677 |
|
|
2678 |
(*_blossom_data)[sb].status = ODD;
|
|
2679 |
matchedToOdd(sb);
|
|
2680 |
_tree_set->insert(sb, tree);
|
|
2681 |
(*_blossom_data)[sb].pred = pred;
|
|
2682 |
(*_blossom_data)[sb].next =
|
|
2683 |
_graph.oppositeArc((*_blossom_data)[tb].next);
|
|
2684 |
|
|
2685 |
pred = (*_blossom_data)[ub].next;
|
|
2686 |
|
|
2687 |
(*_blossom_data)[tb].status = EVEN;
|
|
2688 |
matchedToEven(tb, tree);
|
|
2689 |
_tree_set->insert(tb, tree);
|
|
2690 |
(*_blossom_data)[tb].pred = (*_blossom_data)[tb].next;
|
|
2691 |
}
|
|
2692 |
|
|
2693 |
(*_blossom_data)[subblossoms[id]].status = ODD;
|
|
2694 |
matchedToOdd(subblossoms[id]);
|
|
2695 |
_tree_set->insert(subblossoms[id], tree);
|
|
2696 |
(*_blossom_data)[subblossoms[id]].next = next;
|
|
2697 |
(*_blossom_data)[subblossoms[id]].pred = pred;
|
|
2698 |
|
|
2699 |
} else {
|
|
2700 |
|
|
2701 |
for (int i = (ib + 1) % subblossoms.size();
|
|
2702 |
i != id; i = (i + 2) % subblossoms.size()) {
|
|
2703 |
int sb = subblossoms[i];
|
|
2704 |
int tb = subblossoms[(i + 1) % subblossoms.size()];
|
|
2705 |
(*_blossom_data)[sb].next =
|
|
2706 |
_graph.oppositeArc((*_blossom_data)[tb].next);
|
|
2707 |
}
|
|
2708 |
|
|
2709 |
for (int i = id; i != ib; i = (i + 2) % subblossoms.size()) {
|
|
2710 |
int sb = subblossoms[i];
|
|
2711 |
int tb = subblossoms[(i + 1) % subblossoms.size()];
|
|
2712 |
int ub = subblossoms[(i + 2) % subblossoms.size()];
|
|
2713 |
|
|
2714 |
(*_blossom_data)[sb].status = ODD;
|
|
2715 |
matchedToOdd(sb);
|
|
2716 |
_tree_set->insert(sb, tree);
|
|
2717 |
(*_blossom_data)[sb].next = next;
|
|
2718 |
(*_blossom_data)[sb].pred =
|
|
2719 |
_graph.oppositeArc((*_blossom_data)[tb].next);
|
|
2720 |
|
|
2721 |
(*_blossom_data)[tb].status = EVEN;
|
|
2722 |
matchedToEven(tb, tree);
|
|
2723 |
_tree_set->insert(tb, tree);
|
|
2724 |
(*_blossom_data)[tb].pred =
|
|
2725 |
(*_blossom_data)[tb].next =
|
|
2726 |
_graph.oppositeArc((*_blossom_data)[ub].next);
|
|
2727 |
next = (*_blossom_data)[ub].next;
|
|
2728 |
}
|
|
2729 |
|
|
2730 |
(*_blossom_data)[subblossoms[ib]].status = ODD;
|
|
2731 |
matchedToOdd(subblossoms[ib]);
|
|
2732 |
_tree_set->insert(subblossoms[ib], tree);
|
|
2733 |
(*_blossom_data)[subblossoms[ib]].next = next;
|
|
2734 |
(*_blossom_data)[subblossoms[ib]].pred = pred;
|
|
2735 |
}
|
|
2736 |
_tree_set->erase(blossom);
|
|
2737 |
}
|
|
2738 |
|
|
2739 |
void extractBlossom(int blossom, const Node& base, const Arc& matching) {
|
|
2740 |
if (_blossom_set->trivial(blossom)) {
|
|
2741 |
int bi = (*_node_index)[base];
|
|
2742 |
Value pot = (*_node_data)[bi].pot;
|
|
2743 |
|
|
2744 |
_matching->set(base, matching);
|
|
2745 |
_blossom_node_list.push_back(base);
|
|
2746 |
_node_potential->set(base, pot);
|
|
2747 |
} else {
|
|
2748 |
|
|
2749 |
Value pot = (*_blossom_data)[blossom].pot;
|
|
2750 |
int bn = _blossom_node_list.size();
|
|
2751 |
|
|
2752 |
std::vector<int> subblossoms;
|
|
2753 |
_blossom_set->split(blossom, std::back_inserter(subblossoms));
|
|
2754 |
int b = _blossom_set->find(base);
|
|
2755 |
int ib = -1;
|
|
2756 |
for (int i = 0; i < int(subblossoms.size()); ++i) {
|
|
2757 |
if (subblossoms[i] == b) { ib = i; break; }
|
|
2758 |
}
|
|
2759 |
|
|
2760 |
for (int i = 1; i < int(subblossoms.size()); i += 2) {
|
|
2761 |
int sb = subblossoms[(ib + i) % subblossoms.size()];
|
|
2762 |
int tb = subblossoms[(ib + i + 1) % subblossoms.size()];
|
|
2763 |
|
|
2764 |
Arc m = (*_blossom_data)[tb].next;
|
|
2765 |
extractBlossom(sb, _graph.target(m), _graph.oppositeArc(m));
|
|
2766 |
extractBlossom(tb, _graph.source(m), m);
|
|
2767 |
}
|
|
2768 |
extractBlossom(subblossoms[ib], base, matching);
|
|
2769 |
|
|
2770 |
int en = _blossom_node_list.size();
|
|
2771 |
|
|
2772 |
_blossom_potential.push_back(BlossomVariable(bn, en, pot));
|
|
2773 |
}
|
|
2774 |
}
|
|
2775 |
|
|
2776 |
void extractMatching() {
|
|
2777 |
std::vector<int> blossoms;
|
|
2778 |
for (typename BlossomSet::ClassIt c(*_blossom_set); c != INVALID; ++c) {
|
|
2779 |
blossoms.push_back(c);
|
|
2780 |
}
|
|
2781 |
|
|
2782 |
for (int i = 0; i < int(blossoms.size()); ++i) {
|
|
2783 |
|
|
2784 |
Value offset = (*_blossom_data)[blossoms[i]].offset;
|
|
2785 |
(*_blossom_data)[blossoms[i]].pot += 2 * offset;
|
|
2786 |
for (typename BlossomSet::ItemIt n(*_blossom_set, blossoms[i]);
|
|
2787 |
n != INVALID; ++n) {
|
|
2788 |
(*_node_data)[(*_node_index)[n]].pot -= offset;
|
|
2789 |
}
|
|
2790 |
|
|
2791 |
Arc matching = (*_blossom_data)[blossoms[i]].next;
|
|
2792 |
Node base = _graph.source(matching);
|
|
2793 |
extractBlossom(blossoms[i], base, matching);
|
|
2794 |
}
|
|
2795 |
}
|
|
2796 |
|
|
2797 |
public:
|
|
2798 |
|
|
2799 |
/// \brief Constructor
|
|
2800 |
///
|
|
2801 |
/// Constructor.
|
|
2802 |
MaxWeightedPerfectMatching(const Graph& graph, const WeightMap& weight)
|
|
2803 |
: _graph(graph), _weight(weight), _matching(0),
|
|
2804 |
_node_potential(0), _blossom_potential(), _blossom_node_list(),
|
|
2805 |
_node_num(0), _blossom_num(0),
|
|
2806 |
|
|
2807 |
_blossom_index(0), _blossom_set(0), _blossom_data(0),
|
|
2808 |
_node_index(0), _node_heap_index(0), _node_data(0),
|
|
2809 |
_tree_set_index(0), _tree_set(0),
|
|
2810 |
|
|
2811 |
_delta2_index(0), _delta2(0),
|
|
2812 |
_delta3_index(0), _delta3(0),
|
|
2813 |
_delta4_index(0), _delta4(0),
|
|
2814 |
|
|
2815 |
_delta_sum() {}
|
|
2816 |
|
|
2817 |
~MaxWeightedPerfectMatching() {
|
|
2818 |
destroyStructures();
|
|
2819 |
}
|
|
2820 |
|
|
2821 |
/// \name Execution control
|
|
2822 |
/// The simplest way to execute the algorithm is to use the member
|
|
2823 |
/// \c run() member function.
|
|
2824 |
|
|
2825 |
///@{
|
|
2826 |
|
|
2827 |
/// \brief Initialize the algorithm
|
|
2828 |
///
|
|
2829 |
/// Initialize the algorithm
|
|
2830 |
void init() {
|
|
2831 |
createStructures();
|
|
2832 |
|
|
2833 |
for (ArcIt e(_graph); e != INVALID; ++e) {
|
|
2834 |
_node_heap_index->set(e, BinHeap<Value, ArcIntMap>::PRE_HEAP);
|
|
2835 |
}
|
|
2836 |
for (EdgeIt e(_graph); e != INVALID; ++e) {
|
|
2837 |
_delta3_index->set(e, _delta3->PRE_HEAP);
|
|
2838 |
}
|
|
2839 |
for (int i = 0; i < _blossom_num; ++i) {
|
|
2840 |
_delta2_index->set(i, _delta2->PRE_HEAP);
|
|
2841 |
_delta4_index->set(i, _delta4->PRE_HEAP);
|
|
2842 |
}
|
|
2843 |
|
|
2844 |
int index = 0;
|
|
2845 |
for (NodeIt n(_graph); n != INVALID; ++n) {
|
|
2846 |
Value max = - std::numeric_limits<Value>::max();
|
|
2847 |
for (OutArcIt e(_graph, n); e != INVALID; ++e) {
|
|
2848 |
if (_graph.target(e) == n) continue;
|
|
2849 |
if ((dualScale * _weight[e]) / 2 > max) {
|
|
2850 |
max = (dualScale * _weight[e]) / 2;
|
|
2851 |
}
|
|
2852 |
}
|
|
2853 |
_node_index->set(n, index);
|
|
2854 |
(*_node_data)[index].pot = max;
|
|
2855 |
int blossom =
|
|
2856 |
_blossom_set->insert(n, std::numeric_limits<Value>::max());
|
|
2857 |
|
|
2858 |
_tree_set->insert(blossom);
|
|
2859 |
|
|
2860 |
(*_blossom_data)[blossom].status = EVEN;
|
|
2861 |
(*_blossom_data)[blossom].pred = INVALID;
|
|
2862 |
(*_blossom_data)[blossom].next = INVALID;
|
|
2863 |
(*_blossom_data)[blossom].pot = 0;
|
|
2864 |
(*_blossom_data)[blossom].offset = 0;
|
|
2865 |
++index;
|
|
2866 |
}
|
|
2867 |
for (EdgeIt e(_graph); e != INVALID; ++e) {
|
|
2868 |
int si = (*_node_index)[_graph.u(e)];
|
|
2869 |
int ti = (*_node_index)[_graph.v(e)];
|
|
2870 |
if (_graph.u(e) != _graph.v(e)) {
|
|
2871 |
_delta3->push(e, ((*_node_data)[si].pot + (*_node_data)[ti].pot -
|
|
2872 |
dualScale * _weight[e]) / 2);
|
|
2873 |
}
|
|
2874 |
}
|
|
2875 |
}
|
|
2876 |
|
|
2877 |
/// \brief Starts the algorithm
|
|
2878 |
///
|
|
2879 |
/// Starts the algorithm
|
|
2880 |
bool start() {
|
|
2881 |
enum OpType {
|
|
2882 |
D2, D3, D4
|
|
2883 |
};
|
|
2884 |
|
|
2885 |
int unmatched = _node_num;
|
|
2886 |
while (unmatched > 0) {
|
|
2887 |
Value d2 = !_delta2->empty() ?
|
|
2888 |
_delta2->prio() : std::numeric_limits<Value>::max();
|
|
2889 |
|
|
2890 |
Value d3 = !_delta3->empty() ?
|
|
2891 |
_delta3->prio() : std::numeric_limits<Value>::max();
|
|
2892 |
|
|
2893 |
Value d4 = !_delta4->empty() ?
|
|
2894 |
_delta4->prio() : std::numeric_limits<Value>::max();
|
|
2895 |
|
|
2896 |
_delta_sum = d2; OpType ot = D2;
|
|
2897 |
if (d3 < _delta_sum) { _delta_sum = d3; ot = D3; }
|
|
2898 |
if (d4 < _delta_sum) { _delta_sum = d4; ot = D4; }
|
|
2899 |
|
|
2900 |
if (_delta_sum == std::numeric_limits<Value>::max()) {
|
|
2901 |
return false;
|
|
2902 |
}
|
|
2903 |
|
|
2904 |
switch (ot) {
|
|
2905 |
case D2:
|
|
2906 |
{
|
|
2907 |
int blossom = _delta2->top();
|
|
2908 |
Node n = _blossom_set->classTop(blossom);
|
|
2909 |
Arc e = (*_node_data)[(*_node_index)[n]].heap.top();
|
|
2910 |
extendOnArc(e);
|
|
2911 |
}
|
|
2912 |
break;
|
|
2913 |
case D3:
|
|
2914 |
{
|
|
2915 |
Edge e = _delta3->top();
|
|
2916 |
|
|
2917 |
int left_blossom = _blossom_set->find(_graph.u(e));
|
|
2918 |
int right_blossom = _blossom_set->find(_graph.v(e));
|
|
2919 |
|
|
2920 |
if (left_blossom == right_blossom) {
|
|
2921 |
_delta3->pop();
|
|
2922 |
} else {
|
|
2923 |
int left_tree = _tree_set->find(left_blossom);
|
|
2924 |
int right_tree = _tree_set->find(right_blossom);
|
|
2925 |
|
|
2926 |
if (left_tree == right_tree) {
|
|
2927 |
shrinkOnArc(e, left_tree);
|
|
2928 |
} else {
|
|
2929 |
augmentOnArc(e);
|
|
2930 |
unmatched -= 2;
|
|
2931 |
}
|
|
2932 |
}
|
|
2933 |
} break;
|
|
2934 |
case D4:
|
|
2935 |
splitBlossom(_delta4->top());
|
|
2936 |
break;
|
|
2937 |
}
|
|
2938 |
}
|
|
2939 |
extractMatching();
|
|
2940 |
return true;
|
|
2941 |
}
|
|
2942 |
|
|
2943 |
/// \brief Runs %MaxWeightedPerfectMatching algorithm.
|
|
2944 |
///
|
|
2945 |
/// This method runs the %MaxWeightedPerfectMatching algorithm.
|
|
2946 |
///
|
|
2947 |
/// \note mwm.run() is just a shortcut of the following code.
|
|
2948 |
/// \code
|
|
2949 |
/// mwm.init();
|
|
2950 |
/// mwm.start();
|
|
2951 |
/// \endcode
|
|
2952 |
bool run() {
|
|
2953 |
init();
|
|
2954 |
return start();
|
|
2955 |
}
|
|
2956 |
|
|
2957 |
/// @}
|
|
2958 |
|
|
2959 |
/// \name Primal solution
|
|
2960 |
/// Functions for get the primal solution, ie. the matching.
|
|
2961 |
|
|
2962 |
/// @{
|
|
2963 |
|
|
2964 |
/// \brief Returns the matching value.
|
|
2965 |
///
|
|
2966 |
/// Returns the matching value.
|
|
2967 |
Value matchingValue() const {
|
|
2968 |
Value sum = 0;
|
|
2969 |
for (NodeIt n(_graph); n != INVALID; ++n) {
|
|
2970 |
if ((*_matching)[n] != INVALID) {
|
|
2971 |
sum += _weight[(*_matching)[n]];
|
|
2972 |
}
|
|
2973 |
}
|
|
2974 |
return sum /= 2;
|
|
2975 |
}
|
|
2976 |
|
|
2977 |
/// \brief Returns true when the arc is in the matching.
|
|
2978 |
///
|
|
2979 |
/// Returns true when the arc is in the matching.
|
|
2980 |
bool matching(const Edge& arc) const {
|
|
2981 |
return (*_matching)[_graph.u(arc)] == _graph.direct(arc, true);
|
|
2982 |
}
|
|
2983 |
|
|
2984 |
/// \brief Returns the incident matching arc.
|
|
2985 |
///
|
|
2986 |
/// Returns the incident matching arc from given node.
|
|
2987 |
Arc matching(const Node& node) const {
|
|
2988 |
return (*_matching)[node];
|
|
2989 |
}
|
|
2990 |
|
|
2991 |
/// \brief Returns the mate of the node.
|
|
2992 |
///
|
|
2993 |
/// Returns the adjancent node in a mathcing arc.
|
|
2994 |
Node mate(const Node& node) const {
|
|
2995 |
return _graph.target((*_matching)[node]);
|
|
2996 |
}
|
|
2997 |
|
|
2998 |
/// @}
|
|
2999 |
|
|
3000 |
/// \name Dual solution
|
|
3001 |
/// Functions for get the dual solution.
|
|
3002 |
|
|
3003 |
/// @{
|
|
3004 |
|
|
3005 |
/// \brief Returns the value of the dual solution.
|
|
3006 |
///
|
|
3007 |
/// Returns the value of the dual solution. It should be equal to
|
|
3008 |
/// the primal value scaled by \ref dualScale "dual scale".
|
|
3009 |
Value dualValue() const {
|
|
3010 |
Value sum = 0;
|
|
3011 |
for (NodeIt n(_graph); n != INVALID; ++n) {
|
|
3012 |
sum += nodeValue(n);
|
|
3013 |
}
|
|
3014 |
for (int i = 0; i < blossomNum(); ++i) {
|
|
3015 |
sum += blossomValue(i) * (blossomSize(i) / 2);
|
|
3016 |
}
|
|
3017 |
return sum;
|
|
3018 |
}
|
|
3019 |
|
|
3020 |
/// \brief Returns the value of the node.
|
|
3021 |
///
|
|
3022 |
/// Returns the the value of the node.
|
|
3023 |
Value nodeValue(const Node& n) const {
|
|
3024 |
return (*_node_potential)[n];
|
|
3025 |
}
|
|
3026 |
|
|
3027 |
/// \brief Returns the number of the blossoms in the basis.
|
|
3028 |
///
|
|
3029 |
/// Returns the number of the blossoms in the basis.
|
|
3030 |
/// \see BlossomIt
|
|
3031 |
int blossomNum() const {
|
|
3032 |
return _blossom_potential.size();
|
|
3033 |
}
|
|
3034 |
|
|
3035 |
|
|
3036 |
/// \brief Returns the number of the nodes in the blossom.
|
|
3037 |
///
|
|
3038 |
/// Returns the number of the nodes in the blossom.
|
|
3039 |
int blossomSize(int k) const {
|
|
3040 |
return _blossom_potential[k].end - _blossom_potential[k].begin;
|
|
3041 |
}
|
|
3042 |
|
|
3043 |
/// \brief Returns the value of the blossom.
|
|
3044 |
///
|
|
3045 |
/// Returns the the value of the blossom.
|
|
3046 |
/// \see BlossomIt
|
|
3047 |
Value blossomValue(int k) const {
|
|
3048 |
return _blossom_potential[k].value;
|
|
3049 |
}
|
|
3050 |
|
|
3051 |
/// \brief Lemon iterator for get the items of the blossom.
|
|
3052 |
///
|
|
3053 |
/// Lemon iterator for get the nodes of the blossom. This class
|
|
3054 |
/// provides a common style lemon iterator which gives back a
|
|
3055 |
/// subset of the nodes.
|
|
3056 |
class BlossomIt {
|
|
3057 |
public:
|
|
3058 |
|
|
3059 |
/// \brief Constructor.
|
|
3060 |
///
|
|
3061 |
/// Constructor for get the nodes of the variable.
|
|
3062 |
BlossomIt(const MaxWeightedPerfectMatching& algorithm, int variable)
|
|
3063 |
: _algorithm(&algorithm)
|
|
3064 |
{
|
|
3065 |
_index = _algorithm->_blossom_potential[variable].begin;
|
|
3066 |
_last = _algorithm->_blossom_potential[variable].end;
|
|
3067 |
}
|
|
3068 |
|
|
3069 |
/// \brief Invalid constructor.
|
|
3070 |
///
|
|
3071 |
/// Invalid constructor.
|
|
3072 |
BlossomIt(Invalid) : _index(-1) {}
|
|
3073 |
|
|
3074 |
/// \brief Conversion to node.
|
|
3075 |
///
|
|
3076 |
/// Conversion to node.
|
|
3077 |
operator Node() const {
|
|
3078 |
return _algorithm ? _algorithm->_blossom_node_list[_index] : INVALID;
|
|
3079 |
}
|
|
3080 |
|
|
3081 |
/// \brief Increment operator.
|
|
3082 |
///
|
|
3083 |
/// Increment operator.
|
|
3084 |
BlossomIt& operator++() {
|
|
3085 |
++_index;
|
|
3086 |
if (_index == _last) {
|
|
3087 |
_index = -1;
|
|
3088 |
}
|
|
3089 |
return *this;
|
|
3090 |
}
|
|
3091 |
|
|
3092 |
bool operator==(const BlossomIt& it) const {
|
|
3093 |
return _index == it._index;
|
|
3094 |
}
|
|
3095 |
bool operator!=(const BlossomIt& it) const {
|
|
3096 |
return _index != it._index;
|
|
3097 |
}
|
|
3098 |
|
|
3099 |
private:
|
|
3100 |
const MaxWeightedPerfectMatching* _algorithm;
|
|
3101 |
int _last;
|
|
3102 |
int _index;
|
|
3103 |
};
|
|
3104 |
|
|
3105 |
/// @}
|
|
3106 |
|
|
3107 |
};
|
|
3108 |
|
|
3109 |
|
|
3110 |
} //END OF NAMESPACE LEMON
|
|
3111 |
|
|
3112 |
#endif //LEMON_MAX_MATCHING_H
|