[Lemon-commits] [lemon_svn] jacint: r518 - hugo/trunk/src/work/jacint

Lemon SVN svn at lemon.cs.elte.hu
Mon Nov 6 20:39:54 CET 2006


Author: jacint
Date: Fri Apr 23 23:26:32 2004
New Revision: 518

Added:
   hugo/trunk/src/work/jacint/preflow_res.h
   hugo/trunk/src/work/jacint/preflow_res_comp.cc
Removed:
   hugo/trunk/src/work/jacint/dijkstra.cc
   hugo/trunk/src/work/jacint/dijkstra.h
   hugo/trunk/src/work/jacint/f9
   hugo/trunk/src/work/jacint/fib_heap.h
   hugo/trunk/src/work/jacint/j_graph.h
   hugo/trunk/src/work/jacint/preflow.cc
   hugo/trunk/src/work/jacint/preflowproba.h
Modified:
   hugo/trunk/src/work/jacint/makefile

Log:
ResGraphWrapper running time comparison test.


Modified: hugo/trunk/src/work/jacint/makefile
==============================================================================
--- hugo/trunk/src/work/jacint/makefile	(original)
+++ hugo/trunk/src/work/jacint/makefile	Fri Apr 23 23:26:32 2004
@@ -6,7 +6,7 @@
 CXXFLAGS = -W -Wall -ansi -pedantic -O3 $(INCLUDEDIRS)
 LEDAROOT ?= /ledasrc/LEDA-4.1
 
-BINARIES = preflow #dijkstra_bin_fib_test #preflow # prim
+BINARIES = preflow_res_comp
 
 all: $(BINARIES)
 
@@ -16,15 +16,6 @@
 makefile: .depend
 sinclude .depend
 
-#preflow: 
-#	$(CXX3) $(CXXFLAGS)  -o preflow preflow.cc 
-#
-#dijkstra: 
-#	$(CXX3) $(CXXFLAGS)  -o dijkstra dijkstra.cc
-#
-#prim: 
-#	$(CXX3) $(CXXFLAGS)  -o prim prim.cc
-
 clean:
 	$(RM) *.o $(BINARIES) .depend
 

Added: hugo/trunk/src/work/jacint/preflow_res.h
==============================================================================
--- (empty file)
+++ hugo/trunk/src/work/jacint/preflow_res.h	Fri Apr 23 23:26:32 2004
@@ -0,0 +1,497 @@
+// -*- C++ -*-
+//The same as preflow.h, using ResGraphWrapper
+#ifndef HUGO_PREFLOW_RES_H
+#define HUGO_PREFLOW_RES_H
+
+#define H0 20
+#define H1 1
+
+#include <vector>
+#include <queue>
+#include <graph_wrapper.h>
+
+#include<iostream>
+
+namespace hugo {
+
+  template <typename Graph, typename T, 
+	    typename CapMap=typename Graph::EdgeMap<T>, 
+            typename FlowMap=typename Graph::EdgeMap<T> >
+  class PreflowRes {
+    
+    typedef typename Graph::Node Node;
+    typedef typename Graph::Edge Edge;
+    typedef typename Graph::NodeIt NodeIt;
+    typedef typename Graph::OutEdgeIt OutEdgeIt;
+    typedef typename Graph::InEdgeIt InEdgeIt;
+    
+    const Graph& G;
+    Node s;
+    Node t;
+    const CapMap& capacity;  
+    FlowMap& flow;
+    T value;
+    bool constzero;
+
+    typedef ResGraphWrapper<const Graph, T, CapMap, FlowMap> ResGW;
+    typedef typename ResGW::OutEdgeIt ResOutEdgeIt;
+    typedef typename ResGW::InEdgeIt ResInEdgeIt;
+    typedef typename ResGW::Edge ResEdge;
+ 
+  public:
+    PreflowRes(Graph& _G, Node _s, Node _t, CapMap& _capacity, 
+	    FlowMap& _flow, bool _constzero ) :
+      G(_G), s(_s), t(_t), capacity(_capacity), flow(_flow), constzero(_constzero) {}
+    
+    
+    void run() {
+
+      ResGW res_graph(G, capacity, flow);
+
+      value=0;                //for the subsequent runs
+
+      bool phase=0;        //phase 0 is the 1st phase, phase 1 is the 2nd
+      int n=G.nodeNum(); 
+      int heur0=(int)(H0*n);  //time while running 'bound decrease' 
+      int heur1=(int)(H1*n);  //time while running 'highest label'
+      int heur=heur1;         //starting time interval (#of relabels)
+      bool what_heur=1;       
+      /*
+	what_heur is 0 in case 'bound decrease' 
+	and 1 in case 'highest label'
+      */
+      bool end=false;     
+      /*
+	Needed for 'bound decrease', 'true'
+	means no active nodes are above bound b.
+      */
+      int relabel=0;
+      int k=n-2;  //bound on the highest level under n containing a node
+      int b=k;    //bound on the highest level under n of an active node
+      
+      typename Graph::NodeMap<int> level(G,n);      
+      typename Graph::NodeMap<T> excess(G); 
+
+      std::vector<Node> active(n-1,INVALID);
+      typename Graph::NodeMap<Node> next(G,INVALID);
+      //Stack of the active nodes in level i < n.
+      //We use it in both phases.
+
+      typename Graph::NodeMap<Node> left(G,INVALID);
+      typename Graph::NodeMap<Node> right(G,INVALID);
+      std::vector<Node> level_list(n,INVALID);
+      /*
+	List of the nodes in level i<n.
+      */
+
+
+      /*
+	Reverse_bfs from t in the residual graph, 
+	to find the starting level.
+      */
+      level.set(t,0);
+      std::queue<Node> bfs_queue;
+      bfs_queue.push(t);
+      
+      while (!bfs_queue.empty()) {
+	
+	Node v=bfs_queue.front();	
+	bfs_queue.pop();
+	int l=level[v]+1;
+	
+	ResInEdgeIt e;
+	for(res_graph.first(e,v); res_graph.valid(e); 
+	    res_graph.next(e)) {
+	  Node w=res_graph.tail(e);
+	  if ( level[w] == n && w != s ) {
+	    bfs_queue.push(w);
+	    Node first=level_list[l];
+	    if ( G.valid(first) ) left.set(first,w);
+	    right.set(w,first);
+	    level_list[l]=w;
+	    level.set(w, l);
+	  }
+	}
+      }
+      
+	
+      if ( !constzero ) {
+	/*
+	  Counting the excess
+	*/
+	NodeIt v;
+	for(G.first(v); G.valid(v); G.next(v)) {
+	  T exc=0;
+
+	  InEdgeIt e;
+	  for(G.first(e,v); G.valid(e); G.next(e)) exc+=flow[e];
+	  OutEdgeIt f;
+	  for(G.first(f,v); G.valid(f); G.next(f)) exc-=flow[e];
+
+	  excess.set(v,exc);	  
+
+	  //putting the active nodes into the stack
+	  int lev=level[v];
+	  if ( exc > 0 && lev < n ) {
+	    next.set(v,active[lev]);
+	    active[lev]=v;
+	  }
+	}
+      }
+     
+
+
+      //the starting flow
+      ResOutEdgeIt e;
+      for(res_graph.first(e,s); res_graph.valid(e); 
+	  res_graph.next(e)) {
+	  Node w=res_graph.head(e);
+	  if ( level[w] < n ) {	  
+	    if ( excess[w] == 0 && w!=t ) {
+	      next.set(w,active[level[w]]);
+	      active[level[w]]=w;
+	    }
+	    T rem=res_graph.resCap(e);
+	    excess.set(w, excess[w]+rem);
+	    res_graph.augment(e, rem ); 
+	  }
+      }
+	
+
+      /* 
+	 End of preprocessing 
+      */
+
+
+
+      /*
+	Push/relabel on the highest level active nodes.
+      */	
+      while ( true ) {
+	
+	if ( b == 0 ) {
+	  if ( phase ) break;
+	  
+	  if ( !what_heur && !end && k > 0 ) {
+	    b=k;
+	    end=true;
+	  } else {
+	    phase=1;
+	    level.set(s,0);
+	    std::queue<Node> bfs_queue;
+	    bfs_queue.push(s);
+	    
+	    while (!bfs_queue.empty()) {
+	      
+	      Node v=bfs_queue.front();	
+	      bfs_queue.pop();
+	      int l=level[v]+1;
+	      
+	      ResInEdgeIt e;
+	      for(res_graph.first(e,v); 
+		  res_graph.valid(e); res_graph.next(e)) {
+		Node u=res_graph.tail(e);
+		if ( level[u] >= n ) { 
+		  bfs_queue.push(u);
+		  level.set(u, l);
+		  if ( excess[u] > 0 ) {
+		    next.set(u,active[l]);
+		    active[l]=u;
+		  }
+		}
+	      }
+	    
+	    }
+	    b=n-2;
+	  }
+	    
+	}
+	  
+	  
+	if ( !G.valid(active[b]) ) --b; 
+	else {
+	  end=false;  
+
+	  Node w=active[b];
+	  active[b]=next[w];
+	  int lev=level[w];
+	  T exc=excess[w];
+	  int newlevel=n;       //bound on the next level of w
+	  
+	  ResOutEdgeIt e;
+	  for(res_graph.first(e,w); res_graph.valid(e); res_graph.next(e)) {
+	    
+	    Node v=res_graph.head(e);            
+	    if( lev > level[v] ) {      
+	      /*Push is allowed now*/
+	      
+	      if ( excess[v]==0 && v!=t && v!=s ) {
+		int lev_v=level[v];
+		next.set(v,active[lev_v]);
+		active[lev_v]=v;
+	      }
+	      
+	      T remcap=res_graph.resCap(e);
+	      
+	      if ( remcap >= exc ) {       
+		/*A nonsaturating push.*/
+		res_graph.augment(e, exc);
+		excess.set(v, excess[v]+exc);
+		exc=0;
+		break; 
+		
+	      } else { 
+		/*A saturating push.*/
+		
+		res_graph.augment(e, remcap);
+		excess.set(v, excess[v]+remcap);
+		exc-=remcap;
+	      }
+	    } else if ( newlevel > level[v] ){
+	      newlevel = level[v];
+	    }	    
+	    
+	  }
+
+	excess.set(w, exc);
+	 
+	/*
+	  Relabel
+	*/
+	
+
+	if ( exc > 0 ) {
+	  //now 'lev' is the old level of w
+	
+	  if ( phase ) {
+	    level.set(w,++newlevel);
+	    next.set(w,active[newlevel]);
+	    active[newlevel]=w;
+	    b=newlevel;
+	  } else {
+	    //unlacing starts
+	    Node right_n=right[w];
+	    Node left_n=left[w];
+
+	    if ( G.valid(right_n) ) {
+	      if ( G.valid(left_n) ) {
+		right.set(left_n, right_n);
+		left.set(right_n, left_n);
+	      } else {
+		level_list[lev]=right_n;   
+		left.set(right_n, INVALID);
+	      } 
+	    } else {
+	      if ( G.valid(left_n) ) {
+		right.set(left_n, INVALID);
+	      } else { 
+		level_list[lev]=INVALID;   
+	      } 
+	    } 
+	    //unlacing ends
+		
+	    if ( !G.valid(level_list[lev]) ) {
+	      
+	       //gapping starts
+	      for (int i=lev; i!=k ; ) {
+		Node v=level_list[++i];
+		while ( G.valid(v) ) {
+		  level.set(v,n);
+		  v=right[v];
+		}
+		level_list[i]=INVALID;
+		if ( !what_heur ) active[i]=INVALID;
+	      }	     
+
+	      level.set(w,n);
+	      b=lev-1;
+	      k=b;
+	      //gapping ends
+	    
+	    } else {
+	      
+	      if ( newlevel == n ) level.set(w,n); 
+	      else {
+		level.set(w,++newlevel);
+		next.set(w,active[newlevel]);
+		active[newlevel]=w;
+		if ( what_heur ) b=newlevel;
+		if ( k < newlevel ) ++k;      //now k=newlevel
+		Node first=level_list[newlevel];
+		if ( G.valid(first) ) left.set(first,w);
+		right.set(w,first);
+		left.set(w,INVALID);
+		level_list[newlevel]=w;
+	      }
+	    }
+
+
+	    ++relabel; 
+	    if ( relabel >= heur ) {
+	      relabel=0;
+	      if ( what_heur ) {
+		what_heur=0;
+		heur=heur0;
+		end=false;
+	      } else {
+		what_heur=1;
+		heur=heur1;
+		b=k; 
+	      }
+	    }
+	  } //phase 0
+	  
+	  
+	} // if ( exc > 0 )
+	  
+	
+	}  // if stack[b] is nonempty
+	
+      } // while(true)
+
+
+      value = excess[t];
+      /*Max flow value.*/
+     
+    } //void run()
+
+
+
+
+
+    /*
+      Returns the maximum value of a flow.
+     */
+
+    T flowValue() {
+      return value;
+    }
+
+
+    FlowMap Flow() {
+      return flow;
+      }
+
+
+    
+    void Flow(FlowMap& _flow ) {
+      NodeIt v;
+      for(G.first(v) ; G.valid(v); G.next(v))
+	_flow.set(v,flow[v]);
+    }
+
+
+
+    /*
+      Returns the minimum min cut, by a bfs from s in the residual graph.
+    */
+   
+    template<typename _CutMap>
+    void minMinCut(_CutMap& M) {
+    
+      std::queue<Node> queue;
+      
+      M.set(s,true);      
+      queue.push(s);
+
+      while (!queue.empty()) {
+        Node w=queue.front();
+	queue.pop();
+
+	OutEdgeIt e;
+	for(G.first(e,w) ; G.valid(e); G.next(e)) {
+	  Node v=G.head(e);
+	  if (!M[v] && flow[e] < capacity[e] ) {
+	    queue.push(v);
+	    M.set(v, true);
+	  }
+	} 
+
+	InEdgeIt f;
+	for(G.first(f,w) ; G.valid(f); G.next(f)) {
+	  Node v=G.tail(f);
+	  if (!M[v] && flow[f] > 0 ) {
+	    queue.push(v);
+	    M.set(v, true);
+	  }
+	} 
+      }
+    }
+
+
+  
+    /*
+      Returns the maximum min cut, by a reverse bfs 
+      from t in the residual graph.
+    */
+    
+    template<typename _CutMap>
+    void maxMinCut(_CutMap& M) {
+    
+      std::queue<Node> queue;
+      
+      M.set(t,true);        
+      queue.push(t);
+
+      while (!queue.empty()) {
+        Node w=queue.front();
+	queue.pop();
+
+
+	InEdgeIt e;
+	for(G.first(e,w) ; G.valid(e); G.next(e)) {
+	  Node v=G.tail(e);
+	  if (!M[v] && flow[e] < capacity[e] ) {
+	    queue.push(v);
+	    M.set(v, true);
+	  }
+	}
+	
+	OutEdgeIt f;
+	for(G.first(f,w) ; G.valid(f); G.next(f)) {
+	  Node v=G.head(f);
+	  if (!M[v] && flow[f] > 0 ) {
+	    queue.push(v);
+	    M.set(v, true);
+	  }
+	}
+      }
+
+      NodeIt v;
+      for(G.first(v) ; G.valid(v); G.next(v)) {
+	M.set(v, !M[v]);
+      }
+
+    }
+
+
+
+    template<typename CutMap>
+    void minCut(CutMap& M) {
+      minMinCut(M);
+    }
+
+    
+    void reset_target (Node _t) {t=_t;}
+    void reset_source (Node _s) {s=_s;}
+   
+    template<typename _CapMap>   
+    void reset_cap (_CapMap _cap) {capacity=_cap;}
+
+    template<typename _FlowMap>   
+    void reset_cap (_FlowMap _flow, bool _constzero) {
+      flow=_flow;
+      constzero=_constzero;
+    }
+
+
+
+  };
+
+} //namespace hugo
+
+#endif //PREFLOW_H
+
+
+
+

Added: hugo/trunk/src/work/jacint/preflow_res_comp.cc
==============================================================================
--- (empty file)
+++ hugo/trunk/src/work/jacint/preflow_res_comp.cc	Fri Apr 23 23:26:32 2004
@@ -0,0 +1,125 @@
+/*
+The only difference between preflow.h and preflow_res.h is that the latter
+uses the ResGraphWrapper, while the first does not. (Bfs is implemented by
+hand in both.) This test program runs Preflow and PreflowRes on the same
+graph, tests the result of these implementations and writes the running time
+of them.  */
+#include <iostream>
+
+#include <smart_graph.h>
+#include <dimacs.h>
+#include <preflow.h>
+#include <preflow_res.h>
+#include <time_measure.h>
+
+using namespace hugo;
+
+int main(int, char **) {
+ 
+  typedef SmartGraph Graph;
+  
+  typedef Graph::Node Node;
+  typedef Graph::EdgeIt EdgeIt;
+
+  Graph G;
+  Node s, t;
+  Graph::EdgeMap<int> cap(G);
+  readDimacsMaxFlow(std::cin, G, s, t, cap);
+  Timer ts;
+  
+  std::cout <<
+    "\n  In which way are we faster: using ResGraphWrapper or not?"
+	    <<std::endl;
+  std::cout <<
+    "\n  Running preflow.h on a graph with " << 
+    G.nodeNum() << " nodes and " << G.edgeNum() << " edges..."
+	   << std::endl<<std::endl;
+
+
+  
+  Graph::EdgeMap<int> flow(G,0);
+  Preflow<Graph, int> max_flow_test(G, s, t, cap, flow, 1);
+  ts.reset();
+  max_flow_test.run();
+  std::cout << "Elapsed time NOT using the ResGraphWrapper: " << std::endl 
+	    <<ts << std::endl;
+  
+  Graph::NodeMap<bool> mincut(G);
+  max_flow_test.minMinCut(mincut); 
+  int min_min_cut_value=0;
+  EdgeIt e;
+  for(G.first(e); G.valid(e); G.next(e)) {
+    if (mincut[G.tail(e)] && !mincut[G.head(e)]) min_min_cut_value+=cap[e];
+  }
+
+  Graph::NodeMap<bool> cut(G);
+  max_flow_test.minCut(cut); 
+  int min_cut_value=0;
+  for(G.first(e); G.valid(e); G.next(e)) {
+    if (cut[G.tail(e)] && !cut[G.head(e)]) 
+      min_cut_value+=cap[e];
+  }
+
+  Graph::NodeMap<bool> maxcut(G);
+  max_flow_test.maxMinCut(maxcut); 
+  int max_min_cut_value=0;
+  for(G.first(e); G.valid(e); G.next(e)) {
+    if (maxcut[G.tail(e)] && !maxcut[G.head(e)]) 
+      max_min_cut_value+=cap[e];
+      }
+
+  std::cout << "\n Checking the result: " <<std::endl;  
+  std::cout << "Flow value: "<< max_flow_test.flowValue() << std::endl;
+  std::cout << "Min cut value: "<< min_cut_value << std::endl;
+  std::cout << "Min min cut value: "<< min_min_cut_value << std::endl;
+  std::cout << "Max min cut value: "<< max_min_cut_value << 
+    std::endl;
+
+  if ( max_flow_test.flowValue() == min_cut_value &&
+       min_cut_value == min_min_cut_value &&
+       min_min_cut_value == max_min_cut_value )
+    std::cout << "They are equal! " <<std::endl<< std::endl<<"\n";  
+  
+  Graph::EdgeMap<int> flow2(G,0);
+  PreflowRes<Graph, int> max_flow_test2(G, s, t, cap, flow2, 1);
+  ts.reset();
+  max_flow_test2.run();
+  std::cout << "Elapsed time using the ResGraphWrapper: " << std::endl 
+	    << ts << std::endl;
+  
+  Graph::NodeMap<bool> mincut2(G);
+  max_flow_test2.minMinCut(mincut2); 
+  int min_min_cut_value2=0;
+    for(G.first(e); G.valid(e); G.next(e)) {
+    if (mincut2[G.tail(e)] && !mincut2[G.head(e)]) min_min_cut_value2+=cap[e];
+  }
+
+  Graph::NodeMap<bool> cut2(G);
+  max_flow_test2.minCut(cut2); 
+  int min_cut_value2=0;
+  for(G.first(e); G.valid(e); G.next(e)) {
+    if (cut2[G.tail(e)] && !cut2[G.head(e)]) 
+      min_cut_value2+=cap[e];
+  }
+
+  Graph::NodeMap<bool> maxcut2(G);
+  max_flow_test2.maxMinCut(maxcut2); 
+  int max_min_cut_value2=0;
+  for(G.first(e); G.valid(e); G.next(e)) {
+    if (maxcut2[G.tail(e)] && !maxcut2[G.head(e)]) 
+      max_min_cut_value2+=cap[e];
+      }
+  
+  std::cout << "\n Checking the result: " <<std::endl;  
+  std::cout << "Flow value: "<< max_flow_test2.flowValue() << std::endl;
+  std::cout << "Min cut value: "<< min_cut_value2 << std::endl;
+  std::cout << "Min min cut value: "<< min_min_cut_value2 << std::endl;
+  std::cout << "Max min cut value: "<< max_min_cut_value2 << 
+    std::endl;  
+  if ( max_flow_test.flowValue() == min_cut_value &&
+       min_cut_value == min_min_cut_value &&
+       min_min_cut_value == max_min_cut_value )
+    std::cout << "They are equal! " <<std::endl<<"/n";  
+  
+  return 0;
+}



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