lemon-0.x: src/work/marci/edmonds

     1 // -*- c++ -*-

     2 #ifndef HUGO_EDMONDS_KARP_H

     3 #define HUGO_EDMONDS_KARP_H

     5 #include <algorithm>

     6 #include <list>

     7 #include <iterator>

     9 #include <bfs_iterator.h>

    10 #include <invalid.h>

    11 #include <graph_wrapper.h>

    13 namespace hugo {

    15   template<typename Graph, typename Number, typename FlowMap, typename CapacityMap>

    16   class ResGraph {

    17   public:

    18     typedef typename Graph::Node Node;

    19     typedef typename Graph::NodeIt NodeIt;

    20   private:

    21     typedef typename Graph::SymEdgeIt OldSymEdgeIt;

    22     const Graph& G;

    23     FlowMap& flow;

    24     const CapacityMap& capacity;

    25   public:

    26     ResGraph(const Graph& _G, FlowMap& _flow,

    27 	     const CapacityMap& _capacity) :

    28       G(_G), flow(_flow), capacity(_capacity) { }

    30     class Edge;

    31     class OutEdgeIt;

    32     friend class Edge;

    33     friend class OutEdgeIt;

    35     class Edge {

    36       friend class ResGraph<Graph, Number, FlowMap, CapacityMap>;

    37     protected:

    38       const ResGraph<Graph, Number, FlowMap, CapacityMap>* resG;

    39       OldSymEdgeIt sym;

    40     public:

    41       Edge() { }

    42       //Edge(const Edge& e) : resG(e.resG), sym(e.sym) { }

    43       Number free() const {

    44 	if (resG->G.aNode(sym)==resG->G.tail(sym)) {

    45 	  return (resG->capacity.get(sym)-resG->flow.get(sym));

    46 	} else {

    47 	  return (resG->flow.get(sym));

    48 	}

    49       }

    50       bool valid() const { return sym.valid(); }

    51       void augment(Number a) const {

    52 	if (resG->G.aNode(sym)==resG->G.tail(sym)) {

    53 	  resG->flow.set(sym, resG->flow.get(sym)+a);

    54 	  //resG->flow[sym]+=a;

    55 	} else {

    56 	  resG->flow.set(sym, resG->flow.get(sym)-a);

    57 	  //resG->flow[sym]-=a;

    58 	}

    59       }

    60     };

    62     class OutEdgeIt : public Edge {

    63       friend class ResGraph<Graph, Number, FlowMap, CapacityMap>;

    64     public:

    65       OutEdgeIt() { }

    66       //OutEdgeIt(const OutEdgeIt& e) { resG=e.resG; sym=e.sym; }

    67     private:

    68       OutEdgeIt(const ResGraph<Graph, Number, FlowMap, CapacityMap>& _resG, Node v) {

    69       	resG=&_resG;

    70 	sym=resG->G.template first<OldSymEdgeIt>(v);

    71 	while( sym.valid() && !(free()>0) ) { ++sym; }

    72       }

    73     public:

    74       OutEdgeIt& operator++() {

    75 	++sym;

    76 	while( sym.valid() && !(free()>0) ) { ++sym; }

    77 	return *this;

    78       }

    79     };

    81     void /*getF*/first(OutEdgeIt& e, Node v) const {

    82       e=OutEdgeIt(*this, v);

    83     }

    84     void /*getF*/first(NodeIt& v) const { G./*getF*/first(v); }

    86     template< typename It >

    87     It first() const {

    88       It e;

    89       /*getF*/first(e);

    90       return e;

    91     }

    93     template< typename It >

    94     It first(Node v) const {

    95       It e;

    96       /*getF*/first(e, v);

    97       return e;

    98     }

   100     Node tail(Edge e) const { return G.aNode(e.sym); }

   101     Node head(Edge e) const { return G.bNode(e.sym); }

   103     Node aNode(OutEdgeIt e) const { return G.aNode(e.sym); }

   104     Node bNode(OutEdgeIt e) const { return G.bNode(e.sym); }

   106     int id(Node v) const { return G.id(v); }

   108     template <typename S>

   109     class NodeMap {

   110       typename Graph::NodeMap<S> node_map;

   111     public:

   112       NodeMap(const ResGraph<Graph, Number, FlowMap, CapacityMap>& _G) : node_map(_G.G) { }

   113       NodeMap(const ResGraph<Graph, Number, FlowMap, CapacityMap>& _G, S a) : node_map(_G.G, a) { }

   114       void set(Node nit, S a) { node_map.set(nit, a); }

   115       S get(Node nit) const { return node_map.get(nit); }

   116       S& operator[](Node nit) { return node_map[nit]; }

   117       const S& operator[](Node nit) const { return node_map[nit]; }

   118     };

   120   };

   123   template<typename Graph, typename Number, typename FlowMap, typename CapacityMap>

   124   class ResGraph2 {

   125   public:

   126     typedef typename Graph::Node Node;

   127     typedef typename Graph::NodeIt NodeIt;

   128   private:

   129     //typedef typename Graph::SymEdgeIt OldSymEdgeIt;

   130     typedef typename Graph::OutEdgeIt OldOutEdgeIt;

   131     typedef typename Graph::InEdgeIt OldInEdgeIt;

   133     const Graph& G;

   134     FlowMap& flow;

   135     const CapacityMap& capacity;

   136   public:

   137     ResGraph2(const Graph& _G, FlowMap& _flow,

   138 	     const CapacityMap& _capacity) :

   139       G(_G), flow(_flow), capacity(_capacity) { }

   141     class Edge;

   142     class OutEdgeIt;

   143     friend class Edge;

   144     friend class OutEdgeIt;

   146     class Edge {

   147       friend class ResGraph2<Graph, Number, FlowMap, CapacityMap>;

   148     protected:

   149       const ResGraph2<Graph, Number, FlowMap, CapacityMap>* resG;

   150       //OldSymEdgeIt sym;

   151       OldOutEdgeIt out;

   152       OldInEdgeIt in;

   153       bool out_or_in; //true, iff out

   154     public:

   155       Edge() : out_or_in(true) { }

   156       Number free() const {

   157 	if (out_or_in) {

   158 	  return (resG->capacity.get(out)-resG->flow.get(out));

   159 	} else {

   160 	  return (resG->flow.get(in));

   161 	}

   162       }

   163       bool valid() const {

   164 	return out_or_in && out.valid() || in.valid(); }

   165       void augment(Number a) const {

   166 	if (out_or_in) {

   167 	  resG->flow.set(out, resG->flow.get(out)+a);

   168 	} else {

   169 	  resG->flow.set(in, resG->flow.get(in)-a);

   170 	}

   171       }

   172     };

   174     class OutEdgeIt : public Edge {

   175       friend class ResGraph2<Graph, Number, FlowMap, CapacityMap>;

   176     public:

   177       OutEdgeIt() { }

   178     private:

   179       OutEdgeIt(const ResGraph2<Graph, Number, FlowMap, CapacityMap>& _resG, Node v) {

   180       	resG=&_resG;

   181 	out=resG->G.template first<OldOutEdgeIt>(v);

   182 	while( out.valid() && !(free()>0) ) { ++out; }

   183 	if (!out.valid()) {

   184 	  out_or_in=0;

   185 	  in=resG->G.template first<OldInEdgeIt>(v);

   186 	  while( in.valid() && !(free()>0) ) { ++in; }

   187 	}

   188       }

   189     public:

   190       OutEdgeIt& operator++() {

   191 	if (out_or_in) {

   192 	  Node v=resG->G.aNode(out);

   193 	  ++out;

   194 	  while( out.valid() && !(free()>0) ) { ++out; }

   195 	  if (!out.valid()) {

   196 	    out_or_in=0;

   197 	    in=resG->G.template first<OldInEdgeIt>(v);

   198 	    while( in.valid() && !(free()>0) ) { ++in; }

   199 	  }

   200 	} else {

   201 	  ++in;

   202 	  while( in.valid() && !(free()>0) ) { ++in; }

   203 	}

   204 	return *this;

   205       }

   206     };

   208     void /*getF*/first(OutEdgeIt& e, Node v) const {

   209       e=OutEdgeIt(*this, v);

   210     }

   211     void /*getF*/first(NodeIt& v) const { G./*getF*/first(v); }

   213     template< typename It >

   214     It first() const {

   215       It e;

   216       /*getF*/first(e);

   217       return e;

   218     }

   220     template< typename It >

   221     It first(Node v) const {

   222       It e;

   223       /*getF*/first(e, v);

   224       return e;

   225     }

   227     Node tail(Edge e) const {

   228       return ((e.out_or_in) ? G.aNode(e.out) : G.aNode(e.in)); }

   229     Node head(Edge e) const {

   230       return ((e.out_or_in) ? G.bNode(e.out) : G.bNode(e.in)); }

   232     Node aNode(OutEdgeIt e) const {

   233       return ((e.out_or_in) ? G.aNode(e.out) : G.aNode(e.in)); }

   234     Node bNode(OutEdgeIt e) const {

   235       return ((e.out_or_in) ? G.bNode(e.out) : G.bNode(e.in)); }

   237     int id(Node v) const { return G.id(v); }

   239     template <typename S>

   240     class NodeMap {

   241       typename Graph::NodeMap<S> node_map;

   242     public:

   243       NodeMap(const ResGraph2<Graph, Number, FlowMap, CapacityMap>& _G) : node_map(_G.G) { }

   244       NodeMap(const ResGraph2<Graph, Number, FlowMap, CapacityMap>& _G, S a) : node_map(_G.G, a) { }

   245       void set(Node nit, S a) { node_map.set(nit, a); }

   246       S get(Node nit) const { return node_map.get(nit); }

   247     };

   248   };

   251   template <typename Graph, typename Number, typename FlowMap, typename CapacityMap>

   252   class MaxFlow {

   253   protected:

   254     typedef typename Graph::Node Node;

   255     typedef typename Graph::Edge Edge;

   256     typedef typename Graph::EdgeIt EdgeIt;

   257     typedef typename Graph::OutEdgeIt OutEdgeIt;

   258     typedef typename Graph::InEdgeIt InEdgeIt;

   259     const Graph* g;

   260     Node s;

   261     Node t;

   262     FlowMap* flow;

   263     const CapacityMap* capacity;

   264     typedef ResGraphWrapper<const Graph, Number, FlowMap, CapacityMap > ResGW;

   265     typedef typename ResGW::OutEdgeIt ResGWOutEdgeIt;

   266     typedef typename ResGW::Edge ResGWEdge;

   267   public:

   269     MaxFlow(const Graph& _g, Node _s, Node _t, FlowMap& _flow, const CapacityMap& _capacity) :

   270       g(&_g), s(_s), t(_t), flow(&_flow), capacity(&_capacity) { }

   272     bool augmentOnShortestPath() {

   273       ResGW res_graph(*g, *flow, *capacity);

   274       bool _augment=false;

   276       typedef typename ResGW::NodeMap<bool> ReachedMap;

   277       BfsIterator5< ResGW, ReachedMap > bfs(res_graph);

   278       bfs.pushAndSetReached(s);

   280       typename ResGW::NodeMap<ResGWEdge> pred(res_graph);

   281       pred.set(s, INVALID);

   283       typename ResGW::NodeMap<Number> free(res_graph);

   285       //searching for augmenting path

   286       while ( !bfs.finished() ) {

   287 	ResGWOutEdgeIt e=bfs;

   288 	if (res_graph.valid(e) && bfs.isBNodeNewlyReached()) {

   289 	  Node v=res_graph.tail(e);

   290 	  Node w=res_graph.head(e);

   291 	  pred.set(w, e);

   292 	  if (res_graph.valid(pred[v])) {

   293 	    free.set(w, std::min(free[v], res_graph.resCap(e)));

   294 	  } else {

   295 	    free.set(w, res_graph.resCap(e));

   296 	  }

   297 	  if (res_graph.head(e)==t) { _augment=true; break; }

   298 	}

   300 	++bfs;

   301       } //end of searching augmenting path

   303       if (_augment) {

   304 	Node n=t;

   305 	Number augment_value=free[t];

   306 	while (res_graph.valid(pred[n])) {

   307 	  ResGWEdge e=pred[n];

   308 	  res_graph.augment(e, augment_value);

   309 	  n=res_graph.tail(e);

   310 	}

   311       }

   313       return _augment;

   314     }

   316     template<typename MapGraphWrapper>

   317     class DistanceMap {

   318     protected:

   319       const MapGraphWrapper* g;

   320       typename MapGraphWrapper::NodeMap<int> dist;

   321     public:

   322       DistanceMap(MapGraphWrapper& _g) : g(&_g), dist(*g, g->nodeNum()) { }

   323       void set(const typename MapGraphWrapper::Node& n, int a) { dist[n]=a; }

   324       int operator[](const typename MapGraphWrapper::Node& n)

   325 	{ return dist[n]; }

   326 //       int get(const typename MapGraphWrapper::Node& n) const {

   327 // 	return dist[n]; }

   328 //       bool get(const typename MapGraphWrapper::Edge& e) const {

   329 // 	return (dist.get(g->tail(e))<dist.get(g->head(e))); }

   330       bool operator[](const typename MapGraphWrapper::Edge& e) const {

   331 	return (dist[g->tail(e)]<dist[g->head(e)]);

   332       }

   333     };

   335     template<typename MutableGraph> bool augmentOnBlockingFlow() {

   336       typedef MutableGraph MG;

   337       bool _augment=false;

   339       ResGW res_graph(*g, *flow, *capacity);

   341       typedef typename ResGW::NodeMap<bool> ReachedMap;

   342       BfsIterator5< ResGW, ReachedMap > bfs(res_graph);

   344       bfs.pushAndSetReached(s);

   345       //typename ResGW::NodeMap<int> dist(res_graph); //filled up with 0's

   346       DistanceMap<ResGW> dist(res_graph);

   347       while ( !bfs.finished() ) {

   348 	ResGWOutEdgeIt e=bfs;

   349 	if (res_graph.valid(e) && bfs.isBNodeNewlyReached()) {

   350 	  dist.set(res_graph.head(e), dist[res_graph.tail(e)]+1);

   351 	}

   352 	++bfs;

   353       } //computing distances from s in the residual graph

   355       MG F;

   356       typedef SubGraphWrapper<ResGW, DistanceMap<ResGW> > FilterResGW;

   357       FilterResGW filter_res_graph(res_graph, dist);

   358       typename ResGW::NodeMap<typename MG::Node> res_graph_to_F(res_graph);

   359       {

   360 	typename ResGW::NodeIt n;

   361 	for(res_graph.first(n); res_graph.valid(n); res_graph.next(n)) {

   362 	  res_graph_to_F.set(n, F.addNode());

   363 	}

   364       }

   366       typename MG::Node sF=res_graph_to_F[s];

   367       typename MG::Node tF=res_graph_to_F[t];

   368       typename MG::EdgeMap<ResGWEdge> original_edge(F);

   369       typename MG::EdgeMap<Number> residual_capacity(F);

   371       //Making F to the graph containing the edges of the residual graph

   372       //which are in some shortest paths

   373       {

   374 	typename FilterResGW::EdgeIt e;

   375 	for(filter_res_graph.first(e); filter_res_graph.valid(e); filter_res_graph.next(e)) {

   376 	  //if (dist.get(res_graph.head(e))==dist.get(res_graph.tail(e))+1) {

   377 	  typename MG::Edge f=F.addEdge(res_graph_to_F[res_graph.tail(e)], res_graph_to_F[res_graph.head(e)]);

   378 	  original_edge.update();

   379 	  original_edge.set(f, e);

   380 	  residual_capacity.update();

   381 	  residual_capacity.set(f, res_graph.resCap(e));

   382 	  //}

   383 	}

   384       }

   386       bool __augment=true;

   388       while (__augment) {

   389 	__augment=false;

   390 	//computing blocking flow with dfs

   391 	typedef typename TrivGraphWrapper<MG>::NodeMap<bool> BlockingReachedMap;

   392 	DfsIterator5< TrivGraphWrapper<MG>, BlockingReachedMap > dfs(F);

   393 	typename MG::NodeMap<typename MG::Edge> pred(F);

   394 	pred.set(sF, INVALID);

   395 	//invalid iterators for sources

   397 	typename MG::NodeMap<Number> free(F);

   399 	dfs.pushAndSetReached(sF);

   400 	while (!dfs.finished()) {

   401 	  ++dfs;

   402 	  if (F.valid(/*typename MG::OutEdgeIt*/(dfs))) {

   403 	    if (dfs.isBNodeNewlyReached()) {

   404 	      typename MG::Node v=F.aNode(dfs);

   405 	      typename MG::Node w=F.bNode(dfs);

   406 	      pred.set(w, dfs);

   407 	      if (F.valid(pred[v])) {

   408 		free.set(w, std::min(free[v], residual_capacity[dfs]));

   409 	      } else {

   410 		free.set(w, residual_capacity[dfs]);

   411 	      }

   412 	      if (w==tF) {

   413 		__augment=true;

   414 		_augment=true;

   415 		break;

   416 	      }

   418 	    } else {

   419 	      F.erase(/*typename MG::OutEdgeIt*/(dfs));

   420 	    }

   421 	  }

   422 	}

   424 	if (__augment) {

   425 	  typename MG::Node n=tF;

   426 	  Number augment_value=free[tF];

   427 	  while (F.valid(pred[n])) {

   428 	    typename MG::Edge e=pred[n];

   429 	    res_graph.augment(original_edge[e], augment_value);

   430 	    n=F.tail(e);

   431 	    if (residual_capacity[e]==augment_value)

   432 	      F.erase(e);

   433 	    else

   434 	      residual_capacity.set(e, residual_capacity[e]-augment_value);

   435 	  }

   436 	}

   438       }

   440       return _augment;

   441     }

   443     template<typename MutableGraph> bool augmentOnBlockingFlow1() {

   444       typedef MutableGraph MG;

   445       bool _augment=false;

   447       ResGW res_graph(*g, *flow, *capacity);

   449       //bfs for distances on the residual graph

   450       typedef typename ResGW::NodeMap<bool> ReachedMap;

   451       BfsIterator5< ResGW, ReachedMap > bfs(res_graph);

   452       bfs.pushAndSetReached(s);

   453       typename ResGW::NodeMap<int> dist(res_graph); //filled up with 0's

   455       //F will contain the physical copy of the residual graph

   456       //with the set of edges which are on shortest paths

   457       MG F;

   458       typename ResGW::NodeMap<typename MG::Node> res_graph_to_F(res_graph);

   459       {

   460 	typename ResGW::NodeIt n;

   461 	for(res_graph.first(n); res_graph.valid(n); res_graph.next(n)) {

   462 	  res_graph_to_F.set(n, F.addNode());

   463 	}

   464       }

   466       typename MG::Node sF=res_graph_to_F[s];

   467       typename MG::Node tF=res_graph_to_F[t];

   468       typename MG::EdgeMap<ResGWEdge> original_edge(F);

   469       typename MG::EdgeMap<Number> residual_capacity(F);

   471       while ( !bfs.finished() ) {

   472 	ResGWOutEdgeIt e=bfs;

   473 	if (res_graph.valid(e)) {

   474 	  if (bfs.isBNodeNewlyReached()) {

   475 	    dist.set(res_graph.head(e), dist[res_graph.tail(e)]+1);

   476 	    typename MG::Edge f=F.addEdge(res_graph_to_F[res_graph.tail(e)], res_graph_to_F[res_graph.head(e)]);

   477 	    original_edge.update();

   478 	    original_edge.set(f, e);

   479 	    residual_capacity.update();

   480 	    residual_capacity.set(f, res_graph.resCap(e));

   481 	  } else {

   482 	    if (dist[res_graph.head(e)]==(dist[res_graph.tail(e)]+1)) {

   483 	      typename MG::Edge f=F.addEdge(res_graph_to_F[res_graph.tail(e)], res_graph_to_F[res_graph.head(e)]);

   484 	      original_edge.update();

   485 	      original_edge.set(f, e);

   486 	      residual_capacity.update();

   487 	      residual_capacity.set(f, res_graph.resCap(e));

   488 	    }

   489 	  }

   490 	}

   491 	++bfs;

   492       } //computing distances from s in the residual graph

   494       bool __augment=true;

   496       while (__augment) {

   497 	__augment=false;

   498 	//computing blocking flow with dfs

   499 	typedef typename TrivGraphWrapper<MG>::NodeMap<bool> BlockingReachedMap;

   500 	DfsIterator5< TrivGraphWrapper<MG>, BlockingReachedMap > dfs(F);

   501 	typename MG::NodeMap<typename MG::Edge> pred(F);

   502 	pred.set(sF, INVALID);

   503 	//invalid iterators for sources

   505 	typename MG::NodeMap<Number> free(F);

   507 	dfs.pushAndSetReached(sF);

   508 	while (!dfs.finished()) {

   509 	  ++dfs;

   510 	  if (F.valid(/*typename MG::OutEdgeIt*/(dfs))) {

   511 	    if (dfs.isBNodeNewlyReached()) {

   512 	      typename MG::Node v=F.aNode(dfs);

   513 	      typename MG::Node w=F.bNode(dfs);

   514 	      pred.set(w, dfs);

   515 	      if (F.valid(pred[v])) {

   516 		free.set(w, std::min(free[v], residual_capacity[dfs]));

   517 	      } else {

   518 		free.set(w, residual_capacity[dfs]);

   519 	      }

   520 	      if (w==tF) {

   521 		__augment=true;

   522 		_augment=true;

   523 		break;

   524 	      }

   526 	    } else {

   527 	      F.erase(/*typename MG::OutEdgeIt*/(dfs));

   528 	    }

   529 	  }

   530 	}

   532 	if (__augment) {

   533 	  typename MG::Node n=tF;

   534 	  Number augment_value=free[tF];

   535 	  while (F.valid(pred[n])) {

   536 	    typename MG::Edge e=pred[n];

   537 	    res_graph.augment(original_edge[e], augment_value);

   538 	    n=F.tail(e);

   539 	    if (residual_capacity[e]==augment_value)

   540 	      F.erase(e);

   541 	    else

   542 	      residual_capacity.set(e, residual_capacity[e]-augment_value);

   543 	  }

   544 	}

   546       }

   548       return _augment;

   549     }

   551     bool augmentOnBlockingFlow2() {

   552       bool _augment=false;

   554       ResGW res_graph(*g, *flow, *capacity);

   556       typedef typename ResGW::NodeMap<bool> ReachedMap;

   557       BfsIterator5< ResGW, ReachedMap > bfs(res_graph);

   559       bfs.pushAndSetReached(s);

   560       DistanceMap<ResGW> dist(res_graph);

   561       while ( !bfs.finished() ) {

   562  	ResGWOutEdgeIt e=bfs;

   563  	if (res_graph.valid(e) && bfs.isBNodeNewlyReached()) {

   564  	  dist.set(res_graph.head(e), dist[res_graph.tail(e)]+1);

   565  	}

   566 	++bfs;

   567       } //computing distances from s in the residual graph

   569       //Subgraph containing the edges on some shortest paths

   570       typedef SubGraphWrapper<ResGW, DistanceMap<ResGW> > FilterResGW;

   571       FilterResGW filter_res_graph(res_graph, dist);

   573       //Subgraph, which is able to delete edges which are already

   574       //met by the dfs

   575       typename FilterResGW::NodeMap<typename FilterResGW::OutEdgeIt>

   576  	first_out_edges(filter_res_graph);

   577       typename FilterResGW::NodeIt v;

   578       for(filter_res_graph.first(v); filter_res_graph.valid(v);

   579  	  filter_res_graph.next(v))

   580       {

   581  	typename FilterResGW::OutEdgeIt e;

   582  	filter_res_graph.first(e, v);

   583  	first_out_edges.set(v, e);

   584       }

   585       typedef ErasingFirstGraphWrapper<FilterResGW, typename FilterResGW::

   586 	NodeMap<typename FilterResGW::OutEdgeIt> > ErasingResGW;

   587       ErasingResGW erasing_res_graph(filter_res_graph, first_out_edges);

   589       bool __augment=true;

   591       while (__augment) {

   593  	__augment=false;

   594  	//computing blocking flow with dfs

   595 	typedef typename ErasingResGW::NodeMap<bool> BlockingReachedMap;

   596  	DfsIterator5< ErasingResGW, BlockingReachedMap >

   597  	  dfs(erasing_res_graph);

   598  	typename ErasingResGW::NodeMap<typename ErasingResGW::OutEdgeIt>

   599  	  pred(erasing_res_graph);

   600  	pred.set(s, INVALID);

   601  	//invalid iterators for sources

   603  	typename ErasingResGW::NodeMap<Number> free(erasing_res_graph);

   605  	dfs.pushAndSetReached(s);

   606  	while (!dfs.finished()) {

   607  	  ++dfs;

   608  	  if (erasing_res_graph.valid(

   609  		/*typename ErasingResGW::OutEdgeIt*/(dfs)))

   610  	  {

   611  	    if (dfs.isBNodeNewlyReached()) {

   613  	      typename ErasingResGW::Node v=erasing_res_graph.aNode(dfs);

   614  	      typename ErasingResGW::Node w=erasing_res_graph.bNode(dfs);

   616  	      pred.set(w, /*typename ErasingResGW::OutEdgeIt*/(dfs));

   617  	      if (erasing_res_graph.valid(pred[v])) {

   618  		free.set(w, std::min(free[v], res_graph.resCap(dfs)));

   619  	      } else {

   620  		free.set(w, res_graph.resCap(dfs));

   621  	      }

   623  	      if (w==t) {

   624  		__augment=true;

   625  		_augment=true;

   626  		break;

   627  	      }

   628 	    } else {

   629 	      erasing_res_graph.erase(dfs);

   630 	    }

   631 	  }

   632 	}

   634  	if (__augment) {

   635  	  typename ErasingResGW::Node n=t;

   636  	  Number augment_value=free[n];

   637  	  while (erasing_res_graph.valid(pred[n])) {

   638  	    typename ErasingResGW::OutEdgeIt e=pred[n];

   639  	    res_graph.augment(e, augment_value);

   640  	    n=erasing_res_graph.tail(e);

   641  	    if (res_graph.resCap(e)==0)

   642  	      erasing_res_graph.erase(e);

   643  	  }

   644  	}

   646       } //while (__augment)

   648       return _augment;

   649     }

   651     void run() {

   652       //int num_of_augmentations=0;

   653       while (augmentOnShortestPath()) {

   654 	//while (augmentOnBlockingFlow<MutableGraph>()) {

   655 	//std::cout << ++num_of_augmentations << " ";

   656 	//std::cout<<std::endl;

   657       }

   658     }

   660     template<typename MutableGraph> void run() {

   661       //int num_of_augmentations=0;

   662       //while (augmentOnShortestPath()) {

   663 	while (augmentOnBlockingFlow<MutableGraph>()) {

   664 	//std::cout << ++num_of_augmentations << " ";

   665 	//std::cout<<std::endl;

   666       }

   667     }

   669     Number flowValue() {

   670       Number a=0;

   671       OutEdgeIt e;

   672       for(g->first(e, s); g->valid(e); g->next(e)) {

   673 	a+=(*flow)[e];

   674       }

   675       return a;

   676     }

   678   };

   681 //   template <typename Graph, typename Number, typename FlowMap, typename CapacityMap>

   682 //   class MaxMatching {

   683 //   public:

   684 //     typedef typename Graph::Node Node;

   685 //     typedef typename Graph::NodeIt NodeIt;

   686 //     typedef typename Graph::Edge Edge;

   687 //     typedef typename Graph::EdgeIt EdgeIt;

   688 //     typedef typename Graph::OutEdgeIt OutEdgeIt;

   689 //     typedef typename Graph::InEdgeIt InEdgeIt;

   691 //     typedef typename Graph::NodeMap<bool> SMap;

   692 //     typedef typename Graph::NodeMap<bool> TMap;

   693 //   private:

   694 //     const Graph* G;

   695 //     SMap* S;

   696 //     TMap* T;

   697 //     //Node s;

   698 //     //Node t;

   699 //     FlowMap* flow;

   700 //     const CapacityMap* capacity;

   701 //     typedef ResGraphWrapper<Graph, Number, FlowMap, CapacityMap > AugGraph;

   702 //     typedef typename AugGraph::OutEdgeIt AugOutEdgeIt;

   703 //     typedef typename AugGraph::Edge AugEdge;

   704 //     typename Graph::NodeMap<int> used; //0

   706 //   public:

   707 //     MaxMatching(const Graph& _G, SMap& _S, TMap& _T, FlowMap& _flow, const CapacityMap& _capacity) :

   708 //       G(&_G), S(&_S), T(&_T), flow(&_flow), capacity(&_capacity), used(_G) { }

   709 //     bool augmentOnShortestPath() {

   710 //       AugGraph res_graph(*G, *flow, *capacity);

   711 //       bool _augment=false;

   713 //       typedef typename AugGraph::NodeMap<bool> ReachedMap;

   714 //       BfsIterator5< AugGraph, /*AugOutEdgeIt,*/ ReachedMap > bfs(res_graph);

   715 //       typename AugGraph::NodeMap<AugEdge> pred(res_graph);

   716 //       for(NodeIt s=G->template first<NodeIt>(); G->valid(s); G->next(s)) {

   717 // 	if ((S->get(s)) && (used.get(s)<1) ) {

   718 // 	  //Number u=0;

   719 // 	  //for(OutEdgeIt e=G->template first<OutEdgeIt>(s); G->valid(e); G->next(e))

   720 // 	  //u+=flow->get(e);

   721 // 	  //if (u<1) {

   722 // 	    bfs.pushAndSetReached(s);

   723 // 	    pred.set(s, AugEdge(INVALID));

   724 // 	    //}

   725 // 	}

   726 //       }

   728 //       typename AugGraph::NodeMap<Number> free(res_graph);

   730 //       Node n;

   731 //       //searching for augmenting path

   732 //       while ( !bfs.finished() ) {

   733 // 	AugOutEdgeIt e=bfs;

   734 // 	if (res_graph.valid(e) && bfs.isBNodeNewlyReached()) {

   735 // 	  Node v=res_graph.tail(e);

   736 // 	  Node w=res_graph.head(e);

   737 // 	  pred.set(w, e);

   738 // 	  if (res_graph.valid(pred.get(v))) {

   739 // 	    free.set(w, std::min(free.get(v), res_graph.free(e)));

   740 // 	  } else {

   741 // 	    free.set(w, res_graph.free(e));

   742 // 	  }

   743 // 	  n=res_graph.head(e);

   744 // 	  if (T->get(n) && (used.get(n)<1) ) {

   745 // 	    //Number u=0;

   746 // 	    //for(InEdgeIt f=G->template first<InEdgeIt>(n); G->valid(f); G->next(f))

   747 // 	    //u+=flow->get(f);

   748 // 	    //if (u<1) {

   749 // 	      _augment=true;

   750 // 	      break;

   751 // 	      //}

   752 // 	  }

   753 // 	}

   755 // 	++bfs;

   756 //       } //end of searching augmenting path

   758 //       if (_augment) {

   759 // 	//Node n=t;

   760 // 	used.set(n, 1); //mind2 vegen jav

   761 // 	Number augment_value=free.get(n);

   762 // 	while (res_graph.valid(pred.get(n))) {

   763 // 	  AugEdge e=pred.get(n);

   764 // 	  res_graph.augment(e, augment_value);

   765 // 	  n=res_graph.tail(e);

   766 // 	}

   767 // 	used.set(n, 1); //mind2 vegen jav

   768 //       }

   770 //       return _augment;

   771 //     }

   773 // //     template<typename MutableGraph> bool augmentOnBlockingFlow() {

   774 // //       bool _augment=false;

   776 // //       AugGraph res_graph(*G, *flow, *capacity);

   778 // //       typedef typename AugGraph::NodeMap<bool> ReachedMap;

   779 // //       BfsIterator4< AugGraph, AugOutEdgeIt, ReachedMap > bfs(res_graph);

   785 // //       //typename AugGraph::NodeMap<AugEdge> pred(res_graph);

   786 // //       for(NodeIt s=G->template first<NodeIt>(); G->valid(s); G->next(s)) {

   787 // // 	if (S->get(s)) {

   788 // // 	  Number u=0;

   789 // // 	  for(OutEdgeIt e=G->template first<OutEdgeIt>(s); G->valid(e); G->next(e))

   790 // // 	    u+=flow->get(e);

   791 // // 	  if (u<1) {

   792 // // 	    bfs.pushAndSetReached(s);

   793 // // 	    //pred.set(s, AugEdge(INVALID));

   794 // // 	  }

   795 // // 	}

   796 // //       }

   801 // //       //bfs.pushAndSetReached(s);

   802 // //       typename AugGraph::NodeMap<int> dist(res_graph); //filled up with 0's

   803 // //       while ( !bfs.finished() ) {

   804 // // 	AugOutEdgeIt e=bfs;

   805 // // 	if (res_graph.valid(e) && bfs.isBNodeNewlyReached()) {

   806 // // 	  dist.set(res_graph.head(e), dist.get(res_graph.tail(e))+1);

   807 // // 	}

   809 // // 	++bfs;

   810 // //       } //computing distances from s in the residual graph

   812 // //       MutableGraph F;

   813 // //       typename AugGraph::NodeMap<typename MutableGraph::Node>

   814 // // 	res_graph_to_F(res_graph);

   815 // //       for(typename AugGraph::NodeIt n=res_graph.template first<typename AugGraph::NodeIt>(); res_graph.valid(n); res_graph.next(n)) {

   816 // // 	res_graph_to_F.set(n, F.addNode());

   817 // //       }

   819 // //       typename MutableGraph::Node sF=res_graph_to_F.get(s);

   820 // //       typename MutableGraph::Node tF=res_graph_to_F.get(t);

   822 // //       typename MutableGraph::EdgeMap<AugEdge> original_edge(F);

   823 // //       typename MutableGraph::EdgeMap<Number> residual_capacity(F);

   825 // //       //Making F to the graph containing the edges of the residual graph

   826 // //       //which are in some shortest paths

   827 // //       for(typename AugGraph::EdgeIt e=res_graph.template first<typename AugGraph::EdgeIt>(); res_graph.valid(e); res_graph.next(e)) {

   828 // // 	if (dist.get(res_graph.head(e))==dist.get(res_graph.tail(e))+1) {

   829 // // 	  typename MutableGraph::Edge f=F.addEdge(res_graph_to_F.get(res_graph.tail(e)), res_graph_to_F.get(res_graph.head(e)));

   830 // // 	  original_edge.update();

   831 // // 	  original_edge.set(f, e);

   832 // // 	  residual_capacity.update();

   833 // // 	  residual_capacity.set(f, res_graph.free(e));

   834 // // 	}

   835 // //       }

   837 // //       bool __augment=true;

   839 // //       while (__augment) {

   840 // // 	__augment=false;

   841 // // 	//computing blocking flow with dfs

   842 // // 	typedef typename MutableGraph::NodeMap<bool> BlockingReachedMap;

   843 // // 	DfsIterator4< MutableGraph, typename MutableGraph::OutEdgeIt, BlockingReachedMap > dfs(F);

   844 // // 	typename MutableGraph::NodeMap<typename MutableGraph::Edge> pred(F);

   845 // // 	pred.set(sF, typename MutableGraph::Edge(INVALID));

   846 // // 	//invalid iterators for sources

   848 // // 	typename MutableGraph::NodeMap<Number> free(F);

   850 // // 	dfs.pushAndSetReached(sF);

   851 // // 	while (!dfs.finished()) {

   852 // // 	  ++dfs;

   853 // // 	  if (F.valid(typename MutableGraph::OutEdgeIt(dfs))) {

   854 // // 	    if (dfs.isBNodeNewlyReached()) {

   855 // // 	      typename MutableGraph::Node v=F.aNode(dfs);

   856 // // 	      typename MutableGraph::Node w=F.bNode(dfs);

   857 // // 	      pred.set(w, dfs);

   858 // // 	      if (F.valid(pred.get(v))) {

   859 // // 		free.set(w, std::min(free.get(v), residual_capacity.get(dfs)));

   860 // // 	      } else {

   861 // // 		free.set(w, residual_capacity.get(dfs));

   862 // // 	      }

   863 // // 	      if (w==tF) {

   864 // // 		__augment=true;

   865 // // 		_augment=true;

   866 // // 		break;

   867 // // 	      }

   869 // // 	    } else {

   870 // // 	      F.erase(typename MutableGraph::OutEdgeIt(dfs));

   871 // // 	    }

   872 // // 	  }

   873 // // 	}

   875 // // 	if (__augment) {

   876 // // 	  typename MutableGraph::Node n=tF;

   877 // // 	  Number augment_value=free.get(tF);

   878 // // 	  while (F.valid(pred.get(n))) {

   879 // // 	    typename MutableGraph::Edge e=pred.get(n);

   880 // // 	    res_graph.augment(original_edge.get(e), augment_value);

   881 // // 	    n=F.tail(e);

   882 // // 	    if (residual_capacity.get(e)==augment_value)

   883 // // 	      F.erase(e);

   884 // // 	    else

   885 // // 	      residual_capacity.set(e, residual_capacity.get(e)-augment_value);

   886 // // 	  }

   887 // // 	}

   889 // //       }

   891 // //       return _augment;

   892 // //     }

   893 //     bool augmentOnBlockingFlow2() {

   894 //       bool _augment=false;

   896 //       //typedef ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap> EAugGraph;

   897 //       typedef FilterGraphWrapper< ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap> > EAugGraph;

   898 //       typedef typename EAugGraph::OutEdgeIt EAugOutEdgeIt;

   899 //       typedef typename EAugGraph::Edge EAugEdge;

   901 //       EAugGraph res_graph(*G, *flow, *capacity);

   903 //       //typedef typename EAugGraph::NodeMap<bool> ReachedMap;

   904 //       BfsIterator5<

   905 // 	ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap>,

   906 // 	/*typename ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap>::OutEdgeIt,*/

   907 // 	ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap>::NodeMap<bool> > bfs(res_graph);

   910 //       //typename AugGraph::NodeMap<AugEdge> pred(res_graph);

   911 //       for(NodeIt s=G->template first<NodeIt>(); G->valid(s); G->next(s)) {

   912 // 	if (S->get(s)) {

   913 // 	  Number u=0;

   914 // 	  for(OutEdgeIt e=G->template first<OutEdgeIt>(s); G->valid(e); G->next(e))

   915 // 	    u+=flow->get(e);

   916 // 	  if (u<1) {

   917 // 	    bfs.pushAndSetReached(s);

   918 // 	    //pred.set(s, AugEdge(INVALID));

   919 // 	  }

   920 // 	}

   921 //       }

   924 //       //bfs.pushAndSetReached(s);

   926 //       typename ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap>::

   927 // 	NodeMap<int>& dist=res_graph.dist;

   929 //       while ( !bfs.finished() ) {

   930 // 	typename ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap>::OutEdgeIt e=bfs;

   931 // 	if (res_graph.valid(e) && bfs.isBNodeNewlyReached()) {

   932 // 	  dist.set(res_graph.head(e), dist.get(res_graph.tail(e))+1);

   933 // 	}

   934 // 	++bfs;

   935 //       } //computing distances from s in the residual graph

   937 //       bool __augment=true;

   939 //       while (__augment) {

   941 // 	__augment=false;

   942 // 	//computing blocking flow with dfs

   943 // 	typedef typename EAugGraph::NodeMap<bool> BlockingReachedMap;

   944 // 	DfsIterator5< EAugGraph/*, EAugOutEdgeIt*/, BlockingReachedMap >

   945 // 	  dfs(res_graph);

   946 // 	typename EAugGraph::NodeMap<EAugEdge> pred(res_graph, INVALID);

   947 // 	//pred.set(s, EAugEdge(INVALID));

   948 // 	//invalid iterators for sources

   950 // 	typename EAugGraph::NodeMap<Number> free(res_graph);

   953 // 	//typename AugGraph::NodeMap<AugEdge> pred(res_graph);

   954 //       for(NodeIt s=G->template first<NodeIt>(); G->valid(s); G->next(s)) {

   955 // 	if (S->get(s)) {

   956 // 	  Number u=0;

   957 // 	  for(OutEdgeIt e=G->template first<OutEdgeIt>(s); G->valid(e); G->next(e))

   958 // 	    u+=flow->get(e);

   959 // 	  if (u<1) {

   960 // 	    dfs.pushAndSetReached(s);

   961 // 	    //pred.set(s, AugEdge(INVALID));

   962 // 	  }

   963 // 	}

   964 //       }

   968 //       //dfs.pushAndSetReached(s);

   969 //       typename EAugGraph::Node n;

   970 // 	while (!dfs.finished()) {

   971 // 	  ++dfs;

   972 // 	  if (res_graph.valid(EAugOutEdgeIt(dfs))) {

   973 // 	    if (dfs.isBNodeNewlyReached()) {

   975 // 	      typename EAugGraph::Node v=res_graph.aNode(dfs);

   976 // 	      typename EAugGraph::Node w=res_graph.bNode(dfs);

   978 // 	      pred.set(w, EAugOutEdgeIt(dfs));

   979 // 	      if (res_graph.valid(pred.get(v))) {

   980 // 		free.set(w, std::min(free.get(v), res_graph.free(dfs)));

   981 // 	      } else {

   982 // 		free.set(w, res_graph.free(dfs));

   983 // 	      }

   985 // 	      n=w;

   986 // 	      if (T->get(w)) {

   987 // 		Number u=0;

   988 // 		for(InEdgeIt f=G->template first<InEdgeIt>(n); G->valid(f); G->next(f))

   989 // 		  u+=flow->get(f);

   990 // 		if (u<1) {

   991 // 		  __augment=true;

   992 // 		  _augment=true;

   993 // 		  break;

   994 // 		}

   995 // 	      }

   996 // 	    } else {

   997 // 	      res_graph.erase(dfs);

   998 // 	    }

   999 // 	  }

  1001 // 	}

  1003 // 	if (__augment) {

  1004 // 	  // typename EAugGraph::Node n=t;

  1005 // 	  Number augment_value=free.get(n);

  1006 // 	  while (res_graph.valid(pred.get(n))) {

  1007 // 	    EAugEdge e=pred.get(n);

  1008 // 	    res_graph.augment(e, augment_value);

  1009 // 	    n=res_graph.tail(e);

  1010 // 	    if (res_graph.free(e)==0)

  1011 // 	      res_graph.erase(e);

  1012 // 	  }

  1013 // 	}

  1015 //       }

  1017 //       return _augment;

  1018 //     }

  1019 //     void run() {

  1020 //       //int num_of_augmentations=0;

  1021 //       while (augmentOnShortestPath()) {

  1022 // 	//while (augmentOnBlockingFlow<MutableGraph>()) {

  1023 // 	//std::cout << ++num_of_augmentations << " ";

  1024 // 	//std::cout<<std::endl;

  1025 //       }

  1026 //     }

  1027 // //     template<typename MutableGraph> void run() {

  1028 // //       //int num_of_augmentations=0;

  1029 // //       //while (augmentOnShortestPath()) {

  1030 // // 	while (augmentOnBlockingFlow<MutableGraph>()) {

  1031 // // 	//std::cout << ++num_of_augmentations << " ";

  1032 // // 	//std::cout<<std::endl;

  1033 // //       }

  1034 // //     }

  1035 //     Number flowValue() {

  1036 //       Number a=0;

  1037 //       EdgeIt e;

  1038 //       for(G->/*getF*/first(e); G->valid(e); G->next(e)) {

  1039 // 	a+=flow->get(e);

  1040 //       }

  1041 //       return a;

  1042 //     }

  1043 //   };

  1050 // //   template <typename Graph, typename Number, typename FlowMap, typename CapacityMap>

  1051 // //   class MaxFlow2 {

  1052 // //   public:

  1053 // //     typedef typename Graph::Node Node;

  1054 // //     typedef typename Graph::Edge Edge;

  1055 // //     typedef typename Graph::EdgeIt EdgeIt;

  1056 // //     typedef typename Graph::OutEdgeIt OutEdgeIt;

  1057 // //     typedef typename Graph::InEdgeIt InEdgeIt;

  1058 // //   private:

  1059 // //     const Graph& G;

  1060 // //     std::list<Node>& S;

  1061 // //     std::list<Node>& T;

  1062 // //     FlowMap& flow;

  1063 // //     const CapacityMap& capacity;

  1064 // //     typedef ResGraphWrapper<Graph, Number, FlowMap, CapacityMap > AugGraph;

  1065 // //     typedef typename AugGraph::OutEdgeIt AugOutEdgeIt;

  1066 // //     typedef typename AugGraph::Edge AugEdge;

  1067 // //     typename Graph::NodeMap<bool> SMap;

  1068 // //     typename Graph::NodeMap<bool> TMap;

  1069 // //   public:

  1070 // //     MaxFlow2(const Graph& _G, std::list<Node>& _S, std::list<Node>& _T, FlowMap& _flow, const CapacityMap& _capacity) : G(_G), S(_S), T(_T), flow(_flow), capacity(_capacity), SMap(_G), TMap(_G) {

  1071 // //       for(typename std::list<Node>::const_iterator i=S.begin();

  1072 // // 	  i!=S.end(); ++i) {

  1073 // // 	SMap.set(*i, true);

  1074 // //       }

  1075 // //       for (typename std::list<Node>::const_iterator i=T.begin();

  1076 // // 	   i!=T.end(); ++i) {

  1077 // // 	TMap.set(*i, true);

  1078 // //       }

  1079 // //     }

  1080 // //     bool augment() {

  1081 // //       AugGraph res_graph(G, flow, capacity);

  1082 // //       bool _augment=false;

  1083 // //       Node reached_t_node;

  1085 // //       typedef typename AugGraph::NodeMap<bool> ReachedMap;

  1086 // //       BfsIterator4< AugGraph, AugOutEdgeIt, ReachedMap > bfs(res_graph);

  1087 // //       for(typename std::list<Node>::const_iterator i=S.begin();

  1088 // // 	  i!=S.end(); ++i) {

  1089 // // 	bfs.pushAndSetReached(*i);

  1090 // //       }

  1091 // //       //bfs.pushAndSetReached(s);

  1093 // //       typename AugGraph::NodeMap<AugEdge> pred(res_graph);

  1094 // //       //filled up with invalid iterators

  1096 // //       typename AugGraph::NodeMap<Number> free(res_graph);

  1098 // //       //searching for augmenting path

  1099 // //       while ( !bfs.finished() ) {

  1100 // // 	AugOutEdgeIt e=/*AugOutEdgeIt*/(bfs);

  1101 // // 	if (e.valid() && bfs.isBNodeNewlyReached()) {

  1102 // // 	  Node v=res_graph.tail(e);

  1103 // // 	  Node w=res_graph.head(e);

  1104 // // 	  pred.set(w, e);

  1105 // // 	  if (pred.get(v).valid()) {

  1106 // // 	    free.set(w, std::min(free.get(v), e.free()));

  1107 // // 	  } else {

  1108 // // 	    free.set(w, e.free());

  1109 // // 	  }

  1110 // // 	  if (TMap.get(res_graph.head(e))) {

  1111 // // 	    _augment=true;

  1112 // // 	    reached_t_node=res_graph.head(e);

  1113 // // 	    break;

  1114 // // 	  }

  1115 // // 	}

  1117 // // 	++bfs;

  1118 // //       } //end of searching augmenting path

  1120 // //       if (_augment) {

  1121 // // 	Node n=reached_t_node;

  1122 // // 	Number augment_value=free.get(reached_t_node);

  1123 // // 	while (pred.get(n).valid()) {

  1124 // // 	  AugEdge e=pred.get(n);

  1125 // // 	  e.augment(augment_value);

  1126 // // 	  n=res_graph.tail(e);

  1127 // // 	}

  1128 // //       }

  1130 // //       return _augment;

  1131 // //     }

  1132 // //     void run() {

  1133 // //       while (augment()) { }

  1134 // //     }

  1135 // //     Number flowValue() {

  1136 // //       Number a=0;

  1137 // //       for(typename std::list<Node>::const_iterator i=S.begin();

  1138 // // 	  i!=S.end(); ++i) {

  1139 // // 	for(OutEdgeIt e=G.template first<OutEdgeIt>(*i); e.valid(); ++e) {

  1140 // // 	  a+=flow.get(e);

  1141 // // 	}

  1142 // // 	for(InEdgeIt e=G.template first<InEdgeIt>(*i); e.valid(); ++e) {

  1143 // // 	  a-=flow.get(e);

  1144 // // 	}

  1145 // //       }

  1146 // //       return a;

  1147 // //     }

  1148 // //   };

  1151 } // namespace hugo

  1153 #endif //HUGO_EDMONDS_KARP_H

author	marci
	Mon, 05 Apr 2004 17:38:54 +0000
changeset 307	0fac67bef95a
parent 301	7eb324ed5da3
child 311	6635b11938fe
permissions	-rw-r--r--