1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/work/jacint/matching.h Fri Jan 07 08:39:53 2005 +0000
1.3 @@ -0,0 +1,608 @@
1.4 +// -*- C++ -*-
1.5 +#ifndef LEMON_MAX_MATCHING_H
1.6 +#define LEMON_MAX_MATCHING_H
1.7 +
1.8 +///\ingroup galgs
1.9 +///\file
1.10 +///\brief Maximum matching algorithm.
1.11 +
1.12 +#include <queue>
1.13 +
1.14 +
1.15 +#include <iostream>
1.16 +
1.17 +
1.18 +
1.19 +#include <invalid.h>
1.20 +#include <unionfind.h>
1.21 +#include <lemon/graph_utils.h>
1.22 +
1.23 +namespace lemon {
1.24 +
1.25 + /// \addtogroup galgs
1.26 + /// @{
1.27 +
1.28 + ///Maximum matching algorithms class.
1.29 +
1.30 + ///This class provides Edmonds' alternating forest matching
1.31 + ///algorithm. The starting matching (if any) can be passed to the
1.32 + ///algorithm using read-in functions \ref readNMapNode, \ref
1.33 + ///readNMapEdge or \ref readEMapBool depending on the container. The
1.34 + ///resulting maximum matching can be attained by write-out functions
1.35 + ///\ref writeNMapNode, \ref writeNMapEdge or \ref writeEMapBool
1.36 + ///depending on the preferred container.
1.37 + ///
1.38 + ///The dual side of a mathcing is a map of the nodes to
1.39 + ///MaxMatching::pos_enum, having values D, A and C showing the
1.40 + ///Gallai-Edmonds decomposition of the graph. The nodes in D induce
1.41 + ///a graph with factor-critical components, the nodes in A form the
1.42 + ///barrier, and the nodes in C induce a graph having a perfect
1.43 + ///matching. This decomposition can be attained by calling \ref
1.44 + ///writePos after running the algorithm. Before subsequent runs,
1.45 + ///the function \ref resetPos() must be called.
1.46 + ///
1.47 + ///\param Graph The undirected graph type the algorithm runs on.
1.48 + ///
1.49 + ///\author Jacint Szabo
1.50 + template <typename Graph>
1.51 + class MaxMatching {
1.52 + typedef typename Graph::Node Node;
1.53 + typedef typename Graph::Edge Edge;
1.54 + typedef typename Graph::UndirEdgeIt UndirEdgeIt;
1.55 + typedef typename Graph::NodeIt NodeIt;
1.56 + typedef typename Graph::IncEdgeIt IncEdgeIt;
1.57 +
1.58 + typedef UnionFindEnum<Node, Graph::template NodeMap> UFE;
1.59 +
1.60 + public:
1.61 +
1.62 + ///Indicates the Gallai-Edmonds decomposition of the graph.
1.63 +
1.64 + ///Indicates the Gallai-Edmonds decomposition of the graph, which
1.65 + ///shows an upper bound on the size of a maximum matching. The
1.66 + ///nodes with pos_enum \c D induce a graph with factor-critical
1.67 + ///components, the nodes in \c A form the canonical barrier, and the
1.68 + ///nodes in \c C induce a graph having a perfect matching.
1.69 + enum pos_enum {
1.70 + D=0,
1.71 + A=1,
1.72 + C=2
1.73 + };
1.74 +
1.75 + private:
1.76 +
1.77 + static const int HEUR_density=2;
1.78 + const Graph& g;
1.79 + typename Graph::template NodeMap<Node> mate;
1.80 + typename Graph::template NodeMap<pos_enum> position;
1.81 +
1.82 + public:
1.83 +
1.84 + MaxMatching(const Graph& _g) : g(_g), mate(_g,INVALID), position(_g,C) {}
1.85 +
1.86 + ///Runs Edmonds' algorithm.
1.87 +
1.88 + ///Runs Edmonds' algorithm for sparse graphs (countEdges <=
1.89 + ///2*countNodes), and a heuristical Edmonds' algorithm with a
1.90 + ///heuristic of postponing shrinks for dense graphs. \pre Before
1.91 + ///the subsequent calls \ref resetPos must be called.
1.92 + inline void run();
1.93 +
1.94 + ///Runs Edmonds' algorithm.
1.95 +
1.96 + ///If heur=0 it runs Edmonds' algorithm. If heur=1 it runs
1.97 + ///Edmonds' algorithm with a heuristic of postponing shrinks,
1.98 + ///giving a faster algorithm for dense graphs. \pre Before the
1.99 + ///subsequent calls \ref resetPos must be called.
1.100 + void runEdmonds( int heur );
1.101 +
1.102 + ///Finds a greedy matching starting from the actual matching.
1.103 +
1.104 + ///Starting form the actual matching stored, it finds a maximal
1.105 + ///greedy matching.
1.106 + void greedyMatching();
1.107 +
1.108 + ///Returns the size of the actual matching stored.
1.109 +
1.110 + ///Returns the size of the actual matching stored. After \ref
1.111 + ///run() it returns the size of a maximum matching in the graph.
1.112 + int size () const;
1.113 +
1.114 + ///Resets the map storing the Gallai-Edmonds decomposition.
1.115 +
1.116 + ///Resets the map storing the Gallai-Edmonds decomposition of the
1.117 + ///graph, making it possible to run the algorithm. Must be called
1.118 + ///before all runs of the Edmonds algorithm, except for the first
1.119 + ///run.
1.120 + void resetPos();
1.121 +
1.122 + ///Resets the actual matching to the empty matching.
1.123 +
1.124 + ///Resets the actual matching to the empty matching.
1.125 + ///
1.126 + void resetMatching();
1.127 +
1.128 + ///Reads a matching from a \c Node map of \c Nodes.
1.129 +
1.130 + ///Reads a matching from a \c Node map of \c Nodes. This map must be \e
1.131 + ///symmetric, i.e. if \c map[u]=v then \c map[v]=u must hold, and
1.132 + ///\c uv will be an edge of the matching.
1.133 + template<typename NMapN>
1.134 + void readNMapNode(NMapN& map) {
1.135 + for(NodeIt v(g); v!=INVALID; ++v) {
1.136 + mate.set(v,map[v]);
1.137 + }
1.138 + }
1.139 +
1.140 + ///Writes the stored matching to a \c Node map of \c Nodes.
1.141 +
1.142 + ///Writes the stored matching to a \c Node map of \c Nodes. The
1.143 + ///resulting map will be \e symmetric, i.e. if \c map[u]=v then \c
1.144 + ///map[v]=u will hold, and now \c uv is an edge of the matching.
1.145 + template<typename NMapN>
1.146 + void writeNMapNode (NMapN& map) const {
1.147 + for(NodeIt v(g); v!=INVALID; ++v) {
1.148 + map.set(v,mate[v]);
1.149 + }
1.150 + }
1.151 +
1.152 + ///Reads a matching from a \c Node map of \c Edges.
1.153 +
1.154 + ///Reads a matching from a \c Node map of incident \c Edges. This
1.155 + ///map must have the property that if \c G.target(map[u])=v then \c
1.156 + ///G.target(map[v])=u must hold, and now this edge is an edge of
1.157 + ///the matching.
1.158 + template<typename NMapE>
1.159 + void readNMapEdge(NMapE& map) {
1.160 + for(NodeIt v(g); v!=INVALID; ++v) {
1.161 + Edge e=map[v];
1.162 + if ( g.valid(e) )
1.163 + g.source(e) == v ? mate.set(v,g.target(e)) : mate.set(v,g.source(e));
1.164 + }
1.165 + }
1.166 +
1.167 + ///Writes the matching stored to a \c Node map of \c Edges.
1.168 +
1.169 + ///Writes the stored matching to a \c Node map of incident \c
1.170 + ///Edges. This map will have the property that if \c
1.171 + ///g.target(map[u])=v then \c g.target(map[v])=u holds, and now this
1.172 + ///edge is an edge of the matching.
1.173 + template<typename NMapE>
1.174 + void writeNMapEdge (NMapE& map) const {
1.175 + typename Graph::template NodeMap<bool> todo(g,true);
1.176 + for(NodeIt v(g); v!=INVALID; ++v) {
1.177 + if ( todo[v] && mate[v]!=INVALID ) {
1.178 + Node u=mate[v];
1.179 + for(IncEdgeIt e(g,v); e!=INVALID; ++e) {
1.180 + if ( g.target(e) == u ) {
1.181 + map.set(u,e);
1.182 + map.set(v,e);
1.183 + todo.set(u,false);
1.184 + todo.set(v,false);
1.185 + break;
1.186 + }
1.187 + }
1.188 + }
1.189 + }
1.190 + }
1.191 +
1.192 +
1.193 + ///Reads a matching from an \c Edge map of \c bools.
1.194 +
1.195 + ///Reads a matching from an \c Edge map of \c bools. This map must
1.196 + ///have the property that there are no two adjacent edges \c e, \c
1.197 + ///f with \c map[e]=map[f]=true. The edges \c e with \c
1.198 + ///map[e]=true form the matching.
1.199 + template<typename EMapB>
1.200 + void readEMapBool(EMapB& map) {
1.201 + for(UndirEdgeIt e(g); e!=INVALID; ++e) {
1.202 + if ( map[e] ) {
1.203 + Node u=g.source(e);
1.204 + Node v=g.target(e);
1.205 + mate.set(u,v);
1.206 + mate.set(v,u);
1.207 + }
1.208 + }
1.209 + }
1.210 + //iterable boolmap?
1.211 +
1.212 +
1.213 + ///Writes the matching stored to an \c Edge map of \c bools.
1.214 +
1.215 + ///Writes the matching stored to an \c Edge map of \c bools. This
1.216 + ///map will have the property that there are no two adjacent edges
1.217 + ///\c e, \c f with \c map[e]=map[f]=true. The edges \c e with \c
1.218 + ///map[e]=true form the matching.
1.219 + template<typename EMapB>
1.220 + void writeEMapBool (EMapB& map) const {
1.221 + for(UndirEdgeIt e(g); e!=INVALID; ++e) map.set(e,false);
1.222 +
1.223 + typename Graph::template NodeMap<bool> todo(g,true);
1.224 + for(NodeIt v(g); v!=INVALID; ++v) {
1.225 + if ( todo[v] && mate[v]!=INVALID ) {
1.226 + Node u=mate[v];
1.227 + for(IncEdgeIt e(g,v); e!=INVALID; ++e) {
1.228 + if ( g.target(e) == u ) {
1.229 + map.set(e,true);
1.230 + todo.set(u,false);
1.231 + todo.set(v,false);
1.232 + break;
1.233 + }
1.234 + }
1.235 + }
1.236 + }
1.237 + }
1.238 +
1.239 +
1.240 + ///Writes the canonical decomposition of the graph after running
1.241 + ///the algorithm.
1.242 +
1.243 + ///After calling any run methods of the class, and before calling
1.244 + ///\ref resetPos(), it writes the Gallai-Edmonds canonical
1.245 + ///decomposition of the graph. \c map must be a node map
1.246 + ///of \ref pos_enum 's.
1.247 + template<typename NMapEnum>
1.248 + void writePos (NMapEnum& map) const {
1.249 + for(NodeIt v(g); v!=INVALID; ++v) map.set(v,position[v]);
1.250 + }
1.251 +
1.252 + private:
1.253 +
1.254 + void lateShrink(Node v, typename Graph::template NodeMap<Node>& ear,
1.255 + UFE& blossom, UFE& tree);
1.256 +
1.257 + void normShrink(Node v, typename Graph::NodeMap<Node>& ear,
1.258 + UFE& blossom, UFE& tree);
1.259 +
1.260 + bool noShrinkStep(Node x, typename Graph::NodeMap<Node>& ear,
1.261 + UFE& blossom, UFE& tree, std::queue<Node>& Q);
1.262 +
1.263 + void shrinkStep(Node& top, Node& middle, Node& bottom, typename Graph::NodeMap<Node>& ear,
1.264 + UFE& blossom, UFE& tree, std::queue<Node>& Q);
1.265 +
1.266 + void augment(Node x, typename Graph::NodeMap<Node>& ear,
1.267 + UFE& blossom, UFE& tree);
1.268 + };
1.269 +
1.270 +
1.271 + // **********************************************************************
1.272 + // IMPLEMENTATIONS
1.273 + // **********************************************************************
1.274 +
1.275 +
1.276 + template <typename Graph>
1.277 + void MaxMatching<Graph>::run() {
1.278 + if ( countUndirEdges(g) < HEUR_density*countNodes(g) ) {
1.279 + greedyMatching();
1.280 + runEdmonds(1);
1.281 + } else runEdmonds(0);
1.282 + }
1.283 +
1.284 +
1.285 + template <typename Graph>
1.286 + void MaxMatching<Graph>::runEdmonds( int heur=1 ) {
1.287 +
1.288 + std::cout<<"Entering runEdmonds"<<std::endl;
1.289 +
1.290 + typename Graph::template NodeMap<Node> ear(g,INVALID);
1.291 + //undefined for the base nodes of the blossoms (i.e. for the
1.292 + //representative elements of UFE blossom) and for the nodes in C
1.293 +
1.294 + typename UFE::MapType blossom_base(g);
1.295 + UFE blossom(blossom_base);
1.296 + typename UFE::MapType tree_base(g);
1.297 + UFE tree(tree_base);
1.298 +
1.299 + for(NodeIt v(g); v!=INVALID; ++v) {
1.300 + if ( position[v]==C && mate[v]==INVALID ) {
1.301 + blossom.insert(v);
1.302 + tree.insert(v);
1.303 + position.set(v,D);
1.304 + if ( heur == 1 ) lateShrink( v, ear, blossom, tree );
1.305 + else normShrink( v, ear, blossom, tree );
1.306 + }
1.307 + }
1.308 +
1.309 +
1.310 + std::cout<<" runEdmonds end"<<std::endl;
1.311 +
1.312 +
1.313 + }
1.314 +
1.315 + template <typename Graph>
1.316 + void MaxMatching<Graph>::lateShrink(Node v, typename Graph::template NodeMap<Node>& ear,
1.317 + UFE& blossom, UFE& tree) {
1.318 +
1.319 +
1.320 + std::cout<<"Entering lateShrink"<<std::endl;
1.321 +
1.322 +
1.323 + std::queue<Node> Q; //queue of the totally unscanned nodes
1.324 + Q.push(v);
1.325 + std::queue<Node> R;
1.326 + //queue of the nodes which must be scanned for a possible shrink
1.327 +
1.328 + while ( !Q.empty() ) {
1.329 + Node x=Q.front();
1.330 + Q.pop();
1.331 + if ( noShrinkStep( x, ear, blossom, tree, Q ) ) return;
1.332 + else R.push(x);
1.333 + }
1.334 +
1.335 + while ( !R.empty() ) {
1.336 + Node x=R.front();
1.337 + R.pop();
1.338 +
1.339 + for( IncEdgeIt e(g,x); e!=INVALID ; ++e ) {
1.340 + Node y=g.target(e);
1.341 +
1.342 + if ( position[y] == D && blossom.find(x) != blossom.find(y) ) {
1.343 + //x and y must be in the same tree//biztos? az oddbol d-belive lettek is?
1.344 +
1.345 + typename Graph::template NodeMap<bool> path(g,false);
1.346 +
1.347 + Node b=blossom.find(x);
1.348 + path.set(b,true);
1.349 + b=mate[b];
1.350 + while ( b!=INVALID ) {
1.351 + b=blossom.find(ear[b]);
1.352 + path.set(b,true);
1.353 + b=mate[b];
1.354 + } //going till the root
1.355 +
1.356 + Node top=y;
1.357 + Node middle=blossom.find(top);
1.358 + Node bottom=x;
1.359 + while ( !path[middle] )
1.360 + shrinkStep(top, middle, bottom, ear, blossom, tree, Q);
1.361 +
1.362 + Node base=middle;
1.363 + top=x;
1.364 + middle=blossom.find(top);
1.365 + bottom=y;
1.366 + Node blossom_base=blossom.find(base);
1.367 + while ( middle!=blossom_base )
1.368 + shrinkStep(top, middle, bottom, ear, blossom, tree, Q);
1.369 +
1.370 + blossom.makeRep(base);
1.371 + } // if shrink is needed
1.372 +
1.373 + //most nehany odd node is d-beli lett, es rajuk az is megnezendo hogy mely d-beliekkel szonszedosak mas faban
1.374 +
1.375 + while ( !Q.empty() ) {
1.376 + Node x=Q.front();
1.377 + Q.pop();
1.378 + if ( noShrinkStep(x, ear, blossom, tree, Q) ) return;
1.379 + else R.push(x);
1.380 + }
1.381 + } //for e
1.382 + } // while ( !R.empty() )
1.383 + }
1.384 +
1.385 +
1.386 + template <typename Graph>
1.387 + void MaxMatching<Graph>::normShrink(Node v, typename Graph::NodeMap<Node>& ear,
1.388 + UFE& blossom, UFE& tree) {
1.389 +
1.390 +
1.391 + std::cout<<"Entering normShrink with node "<<g.id(v)<<std::endl;
1.392 +
1.393 +
1.394 + std::queue<Node> Q; //queue of the unscanned nodes
1.395 + Q.push(v);
1.396 + while ( !Q.empty() ) {
1.397 +
1.398 + std::cout<<"beginning of norm while"<<std::endl;
1.399 +
1.400 + Node x=Q.front();
1.401 + Q.pop();
1.402 +
1.403 + for( IncEdgeIt e(g,x); e!=INVALID; ++e ) {
1.404 +
1.405 +
1.406 + for( IncEdgeIt f(g,x); f!=INVALID; ++f ) {
1.407 + std::cout<<"Starting for." <<std::endl;
1.408 + std::cout<<"edges " << g.id(f)<< " : " << g.id(g.target(f))<<std::endl;
1.409 + std::cout<<"Ending for." <<std::endl;
1.410 + }
1.411 +
1.412 + std::cout<<"Ending the whole for." <<std::endl;
1.413 + std::cout<<"for (In normShrink) with edge " << g.id(e)<< " : " << g.id(x);
1.414 +
1.415 + Node y=g.target(e);
1.416 +
1.417 + std::cout<<" "<<g.id(y)<<std::endl;
1.418 +
1.419 + switch ( position[y] ) {
1.420 + case D: //x and y must be in the same tree //asszem nem!!!
1.421 +
1.422 + std::cout<<" pos[y] " << position[y]<<std::endl;
1.423 + std::cout<<" blossom.find(x) ="<< g.id(blossom.find(x))<<std::endl;
1.424 + std::cout<<" blossom.find(y) ="<< g.id(blossom.find(y))<<std::endl;
1.425 +
1.426 +
1.427 + if ( blossom.find(x) != blossom.find(y) ) { //shrink
1.428 + typename Graph::template NodeMap<bool> path(g,false);
1.429 +
1.430 + Node b=blossom.find(x);
1.431 + path.set(b,true);
1.432 + b=mate[b];
1.433 + while ( b!=INVALID ) {
1.434 + b=blossom.find(ear[b]);
1.435 + path.set(b,true);
1.436 + b=mate[b];
1.437 + } //going till the root
1.438 +
1.439 + Node top=y;
1.440 + Node middle=blossom.find(top);
1.441 + Node bottom=x;
1.442 + while ( !path[middle] )
1.443 + shrinkStep(top, middle, bottom, ear, blossom, tree, Q);
1.444 +
1.445 + Node base=middle;
1.446 + top=x;
1.447 + middle=blossom.find(top);
1.448 + bottom=y;
1.449 + Node blossom_base=blossom.find(base);
1.450 + while ( middle!=blossom_base )
1.451 + shrinkStep(top, middle, bottom, ear, blossom, tree, Q);
1.452 +
1.453 + blossom.makeRep(base);
1.454 + }
1.455 + break;
1.456 + case C:
1.457 + if ( mate[y]!=INVALID ) { //grow
1.458 +
1.459 + std::cout<<"grow"<<std::endl;
1.460 +
1.461 + ear.set(y,x);
1.462 + Node w=mate[y];
1.463 + blossom.insert(w);
1.464 + position.set(y,A);
1.465 + position.set(w,D);
1.466 + tree.insert(y);
1.467 + tree.insert(w);
1.468 + tree.join(y,blossom.find(x));
1.469 + tree.join(w,y);
1.470 + Q.push(w);
1.471 +
1.472 + } else { //augment
1.473 +
1.474 + std::cout<<"augment"<<std::endl;
1.475 +
1.476 + augment(x, ear, blossom, tree);
1.477 + mate.set(x,y);
1.478 + mate.set(y,x);
1.479 + return;
1.480 + } //if
1.481 +
1.482 + std::cout<<"end c eset"<<std::endl;
1.483 + break;
1.484 + default: break;
1.485 + }
1.486 + std::cout<<"end switch"<<std::endl;
1.487 + }
1.488 + }
1.489 + }
1.490 +
1.491 + template <typename Graph>
1.492 + void MaxMatching<Graph>::greedyMatching() {
1.493 + for(NodeIt v(g); v!=INVALID; ++v)
1.494 + if ( mate[v]==INVALID ) {
1.495 + for( IncEdgeIt e(g,v); e!=INVALID ; ++e ) {
1.496 + Node y=g.target(e);
1.497 + if ( mate[y]==INVALID && y!=v ) {
1.498 + mate.set(v,y);
1.499 + mate.set(y,v);
1.500 + break;
1.501 + }
1.502 + }
1.503 + }
1.504 + }
1.505 +
1.506 + template <typename Graph>
1.507 + int MaxMatching<Graph>::size() const {
1.508 + int s=0;
1.509 + for(NodeIt v(g); v!=INVALID; ++v) {
1.510 + if ( mate[v]!=INVALID ) {
1.511 + ++s;
1.512 + }
1.513 + }
1.514 + return (int)s/2;
1.515 + }
1.516 +
1.517 + template <typename Graph>
1.518 + void MaxMatching<Graph>::resetPos() {
1.519 + for(NodeIt v(g); v!=INVALID; ++v)
1.520 + position.set(v,C);
1.521 + }
1.522 +
1.523 + template <typename Graph>
1.524 + void MaxMatching<Graph>::resetMatching() {
1.525 + for(NodeIt v(g); v!=INVALID; ++v)
1.526 + mate.set(v,INVALID);
1.527 + }
1.528 +
1.529 + template <typename Graph>
1.530 + bool MaxMatching<Graph>::noShrinkStep(Node x, typename Graph::NodeMap<Node>& ear,
1.531 + UFE& blossom, UFE& tree, std::queue<Node>& Q) {
1.532 + for( IncEdgeIt e(g,x); e!= INVALID; ++e ) {
1.533 + Node y=g.target(e);
1.534 +
1.535 + if ( position[y]==C ) {
1.536 + if ( mate[y]!=INVALID ) { //grow
1.537 + ear.set(y,x);
1.538 + Node w=mate[y];
1.539 + blossom.insert(w);
1.540 + position.set(y,A);
1.541 + position.set(w,D);
1.542 + tree.insert(y);
1.543 + tree.insert(w);
1.544 + tree.join(y,blossom.find(x));
1.545 + tree.join(w,y);
1.546 + Q.push(w);
1.547 + } else { //augment
1.548 + augment(x, ear, blossom, tree);
1.549 + mate.set(x,y);
1.550 + mate.set(y,x);
1.551 + return true;
1.552 + }
1.553 + }
1.554 + }
1.555 + return false;
1.556 + }
1.557 +
1.558 + template <typename Graph>
1.559 + void MaxMatching<Graph>::shrinkStep(Node& top, Node& middle, Node& bottom, typename Graph::NodeMap<Node>& ear,
1.560 + UFE& blossom, UFE& tree, std::queue<Node>& Q) {
1.561 + ear.set(top,bottom);
1.562 + Node t=top;
1.563 + while ( t!=middle ) {
1.564 + Node u=mate[t];
1.565 + t=ear[u];
1.566 + ear.set(t,u);
1.567 + }
1.568 + bottom=mate[middle];
1.569 + position.set(bottom,D);
1.570 + Q.push(bottom);
1.571 + top=ear[bottom];
1.572 + Node oldmiddle=middle;
1.573 + middle=blossom.find(top);
1.574 + tree.erase(bottom);
1.575 + tree.erase(oldmiddle);
1.576 + blossom.insert(bottom);
1.577 + blossom.join(bottom, oldmiddle);
1.578 + blossom.join(top, oldmiddle);
1.579 + }
1.580 +
1.581 + template <typename Graph>
1.582 + void MaxMatching<Graph>::augment(Node x, typename Graph::NodeMap<Node>& ear,
1.583 + UFE& blossom, UFE& tree) {
1.584 + Node v=mate[x];
1.585 + while ( v!=INVALID ) {
1.586 +
1.587 + Node u=ear[v];
1.588 + mate.set(v,u);
1.589 + Node tmp=v;
1.590 + v=mate[u];
1.591 + mate.set(u,tmp);
1.592 + }
1.593 + typename UFE::ItemIt it;
1.594 + for (tree.first(it,blossom.find(x)); tree.valid(it); tree.next(it)) {
1.595 + if ( position[it] == D ) {
1.596 + typename UFE::ItemIt b_it;
1.597 + for (blossom.first(b_it,it); blossom.valid(b_it); blossom.next(b_it)) {
1.598 + position.set( b_it ,C);
1.599 + }
1.600 + blossom.eraseClass(it);
1.601 + } else position.set( it ,C);
1.602 + }
1.603 + tree.eraseClass(x);
1.604 +
1.605 + }
1.606 +
1.607 + /// @}
1.608 +
1.609 +} //END OF NAMESPACE LEMON
1.610 +
1.611 +#endif //EDMONDS_H