[Lemon-commits] [lemon_svn] marci: r298 - in hugo/trunk/src/work: . marci

[Lemon SVN]

Author: marci
Date: Fri Mar 19 10:09:20 2004
New Revision: 298

Modified:
   hugo/trunk/src/work/edmonds_karp.h
   hugo/trunk/src/work/marci/dimacs.h
   hugo/trunk/src/work/marci/edmonds_karp_demo.cc

Log:
.


Modified: hugo/trunk/src/work/edmonds_karp.h
==============================================================================
--- hugo/trunk/src/work/edmonds_karp.h	(original)
+++ hugo/trunk/src/work/edmonds_karp.h	Fri Mar 19 10:09:20 2004
@@ -413,6 +413,109 @@
             
       return _augment;
     }
+    template<typename MutableGraph> bool augmentOnBlockingFlow1() {      
+      bool _augment=false;
+
+      AugGraph res_graph(*G, *flow, *capacity);
+
+      //bfs for distances on the residual graph
+      typedef typename AugGraph::NodeMap<bool> ReachedMap;
+      BfsIterator4< AugGraph, AugOutEdgeIt, ReachedMap > bfs(res_graph);
+      bfs.pushAndSetReached(s);
+      typename AugGraph::NodeMap<int> dist(res_graph); //filled up with 0's
+
+      //F will contain the physical copy of the residual graph
+      //with the set of edges which areon shortest paths
+      MutableGraph F;
+      typename AugGraph::NodeMap<typename MutableGraph::Node> 
+	res_graph_to_F(res_graph);
+      for(typename AugGraph::NodeIt n=res_graph.template first<typename AugGraph::NodeIt>(); res_graph.valid(n); res_graph.next(n)) {
+	res_graph_to_F.set(n, F.addNode());
+      }
+      typename MutableGraph::Node sF=res_graph_to_F.get(s);
+      typename MutableGraph::Node tF=res_graph_to_F.get(t);
+      typename MutableGraph::EdgeMap<AugEdge> original_edge(F);
+      typename MutableGraph::EdgeMap<Number> residual_capacity(F);
+
+      while ( !bfs.finished() ) { 
+	AugOutEdgeIt e=bfs;
+	if (res_graph.valid(e)) {
+	  if (bfs.isBNodeNewlyReached()) {
+	    dist.set(res_graph.head(e), dist.get(res_graph.tail(e))+1);
+	    typename MutableGraph::Edge f=F.addEdge(res_graph_to_F.get(res_graph.tail(e)), res_graph_to_F.get(res_graph.head(e)));
+	    original_edge.update();
+	    original_edge.set(f, e);
+	    residual_capacity.update();
+	    residual_capacity.set(f, res_graph.free(e));
+	  } else {
+	    if (dist.get(res_graph.head(e))==(dist.get(res_graph.tail(e))+1)) {
+	      typename MutableGraph::Edge f=F.addEdge(res_graph_to_F.get(res_graph.tail(e)), res_graph_to_F.get(res_graph.head(e)));
+	      original_edge.update();
+	      original_edge.set(f, e);
+	      residual_capacity.update();
+	      residual_capacity.set(f, res_graph.free(e));
+	    }
+	  }
+	}
+	++bfs;
+      } //computing distances from s in the residual graph
+
+      bool __augment=true;
+
+      while (__augment) {
+	__augment=false;
+	//computing blocking flow with dfs
+	typedef typename MutableGraph::NodeMap<bool> BlockingReachedMap;
+	DfsIterator4< MutableGraph, typename MutableGraph::OutEdgeIt, BlockingReachedMap > dfs(F);
+	typename MutableGraph::NodeMap<typename MutableGraph::Edge> pred(F);
+	pred.set(sF, typename MutableGraph::Edge(INVALID));
+	//invalid iterators for sources
+
+	typename MutableGraph::NodeMap<Number> free(F);
+
+	dfs.pushAndSetReached(sF);      
+	while (!dfs.finished()) {
+	  ++dfs;
+	  if (F.valid(typename MutableGraph::OutEdgeIt(dfs))) {
+	    if (dfs.isBNodeNewlyReached()) {
+	      typename MutableGraph::Node v=F.aNode(dfs);
+	      typename MutableGraph::Node w=F.bNode(dfs);
+	      pred.set(w, dfs);
+	      if (F.valid(pred.get(v))) {
+		free.set(w, std::min(free.get(v), residual_capacity.get(dfs)));
+	      } else {
+		free.set(w, residual_capacity.get(dfs)); 
+	      }
+	      if (w==tF) { 
+		__augment=true; 
+		_augment=true;
+		break; 
+	      }
+	      
+	    } else {
+	      F.erase(typename MutableGraph::OutEdgeIt(dfs));
+	    }
+	  } 
+	}
+
+	if (__augment) {
+	  typename MutableGraph::Node n=tF;
+	  Number augment_value=free.get(tF);
+	  while (F.valid(pred.get(n))) { 
+	    typename MutableGraph::Edge e=pred.get(n);
+	    res_graph.augment(original_edge.get(e), augment_value); 
+	    n=F.tail(e);
+	    if (residual_capacity.get(e)==augment_value) 
+	      F.erase(e); 
+	    else 
+	      residual_capacity.set(e, residual_capacity.get(e)-augment_value);
+	  }
+	}
+	
+      }
+            
+      return _augment;
+    }
     bool augmentOnBlockingFlow2() {
       bool _augment=false;
 

Modified: hugo/trunk/src/work/marci/dimacs.h
==============================================================================
--- hugo/trunk/src/work/marci/dimacs.h	(original)
+++ hugo/trunk/src/work/marci/dimacs.h	Fri Mar 19 10:09:20 2004
@@ -25,9 +25,6 @@
       case 'c': //comment
 	getline(is, str);
 	break;
-//       case 't': //type
-// 	getline(is, str);
-// 	break;
       case 'p': //problem definition
 	is >> problem >> n >> m;
 	getline(is, str);

Modified: hugo/trunk/src/work/marci/edmonds_karp_demo.cc
==============================================================================
--- hugo/trunk/src/work/marci/edmonds_karp_demo.cc	(original)
+++ hugo/trunk/src/work/marci/edmonds_karp_demo.cc	Fri Mar 19 10:09:20 2004
@@ -34,8 +34,8 @@
 
   typedef ListGraph MutableGraph;
 
-//  typedef SmartGraph Graph;
-  typedef ListGraph Graph;
+  typedef SmartGraph Graph;
+  //typedef ListGraph Graph;
   typedef Graph::Node Node;
   typedef Graph::EdgeIt EdgeIt;
 
@@ -114,6 +114,35 @@
   }
 
   {
+    std::cout << "SmartGraph..." << std::endl;
+    std::cout << "edmonds karp demo (physical blocking flow 1 augmentation)..." << std::endl;
+    Graph::EdgeMap<int> flow(G); //0 flow
+
+    Timer ts;
+    ts.reset();
+
+    MaxFlow<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> > max_flow_test(G, s, t, flow, cap);
+    //max_flow_test.augmentWithBlockingFlow<Graph>();
+    int i=0;
+    while (max_flow_test.augmentOnBlockingFlow1<MutableGraph>()) { 
+//     for(EdgeIt e=G.template first<EdgeIt>(); e.valid(); ++e) { 
+//       std::cout<<"("<<G.tail(e)<< "-"<<flow.get(e)<<"->"<<G.head(e)<<") ";
+//     }
+//     std::cout<<std::endl;
+      ++i; 
+    }
+
+//   std::cout << "maximum flow: "<< std::endl;
+//   for(EdgeIt e=G.first<EdgeIt>(); e.valid(); ++e) { 
+//     std::cout<<"("<<G.tail(e)<< "-"<<flow.get(e)<<"->"<<G.head(e)<<") ";
+//   }
+//   std::cout<<std::endl;
+    std::cout << "elapsed time: " << ts << std::endl;
+    std::cout << "number of augmentation phases: " << i << std::endl; 
+    std::cout << "flow value: "<< max_flow_test.flowValue() << std::endl;
+  }
+
+  {
     std::cout << "edmonds karp demo (on-the-fly blocking flow augmentation)..." << std::endl;
     Graph::EdgeMap<int> flow(G); //0 flow