[Lemon-commits] [lemon_svn] jacint: r90 - hugo/trunk/src/work/jacint

Lemon SVN svn at lemon.cs.elte.hu
Mon Nov 6 20:37:16 CET 2006


Author: jacint
Date: Fri Feb 13 16:12:10 2004
New Revision: 90

Added:
   hugo/trunk/src/work/jacint/flow_test.cc
   hugo/trunk/src/work/jacint/makefile
   hugo/trunk/src/work/jacint/preflow_push_hl.h

Log:
modern valtozat


Added: hugo/trunk/src/work/jacint/flow_test.cc
==============================================================================
--- (empty file)
+++ hugo/trunk/src/work/jacint/flow_test.cc	Fri Feb 13 16:12:10 2004
@@ -0,0 +1,247 @@
+#include <iostream>
+#include <vector>
+#include <string>
+
+#include <marci_list_graph.hh>
+#include <marci_graph_traits.hh>
+#include <marci_property_vector.hh>
+#include <preflow_push_hl.hh>
+#include <preflow_push_max_flow.hh>
+#include <reverse_bfs.hh>
+//#include <dijkstra.hh>
+
+using namespace marci;
+
+
+int main (int, char*[])
+{
+  typedef graph_traits<list_graph>::node_iterator node_iterator;
+  typedef graph_traits<list_graph>::edge_iterator edge_iterator;
+  typedef graph_traits<list_graph>::each_node_iterator each_node_iterator;
+  typedef graph_traits<list_graph>::each_edge_iterator each_edge_iterator;
+  typedef graph_traits<list_graph>::out_edge_iterator out_edge_iterator;
+  typedef graph_traits<list_graph>::in_edge_iterator in_edge_iterator;
+  typedef graph_traits<list_graph>::sym_edge_iterator sym_edge_iterator;
+
+  list_graph flow_test;
+ 
+    //Ahuja könyv példája, maxflowvalue=13
+  node_iterator s=flow_test.add_node();
+  node_iterator v1=flow_test.add_node();
+  node_iterator v2=flow_test.add_node();
+  node_iterator v3=flow_test.add_node();
+  node_iterator v4=flow_test.add_node();
+  node_iterator v5=flow_test.add_node();
+  node_iterator t=flow_test.add_node();
+  
+  node_property_vector<list_graph, std::string> node_name(flow_test);
+  node_name.put(s, "s");
+  node_name.put(v1, "v1");
+  node_name.put(v2, "v2");
+  node_name.put(v3, "v3");
+  node_name.put(v4, "v4");
+  node_name.put(v5, "v5");
+  node_name.put(t, "t");
+
+  edge_iterator s_v1=flow_test.add_edge(s, v1);
+  edge_iterator s_v2=flow_test.add_edge(s, v2);
+  edge_iterator s_v3=flow_test.add_edge(s, v3);
+  edge_iterator v2_v4=flow_test.add_edge(v2, v4);
+  edge_iterator v2_v5=flow_test.add_edge(v2, v5);
+  edge_iterator v3_v5=flow_test.add_edge(v3, v5);
+  edge_iterator v4_t=flow_test.add_edge(v4, t);
+  edge_iterator v5_t=flow_test.add_edge(v5, t);
+  edge_iterator v2_s=flow_test.add_edge(v2, s);
+  
+  edge_property_vector<list_graph, int> cap(flow_test);  
+  cap.put(s_v1, 0);
+  cap.put(s_v2, 10);
+  cap.put(s_v3, 10);
+  cap.put(v2_v4, 5);
+  cap.put(v2_v5, 8);
+  cap.put(v3_v5, 5);
+  cap.put(v4_t, 8);
+  cap.put(v5_t, 8);
+  cap.put(v2_s, 0);
+
+
+  
+  //Marci példája, maxflowvalue=23
+  /*  node_iterator s=flow_test.add_node();
+  node_iterator v1=flow_test.add_node();
+  node_iterator v2=flow_test.add_node();
+  node_iterator v3=flow_test.add_node();
+  node_iterator v4=flow_test.add_node();
+  node_iterator t=flow_test.add_node();
+  node_iterator w=flow_test.add_node();
+
+  
+  node_property_vector<list_graph, std::string> node_name(flow_test);
+  node_name.put(s, "s");
+  node_name.put(v1, "v1");
+  node_name.put(v2, "v2");
+  node_name.put(v3, "v3");
+  node_name.put(v4, "v4");
+  node_name.put(t, "t");
+  node_name.put(w, "w");
+
+  edge_iterator s_v1=flow_test.add_edge(s, v1);
+  edge_iterator s_v2=flow_test.add_edge(s, v2);
+  edge_iterator v1_v2=flow_test.add_edge(v1, v2);
+  edge_iterator v2_v1=flow_test.add_edge(v2, v1);
+  edge_iterator v1_v3=flow_test.add_edge(v1, v3);
+  edge_iterator v3_v2=flow_test.add_edge(v3, v2);
+  edge_iterator v2_v4=flow_test.add_edge(v2, v4);
+  edge_iterator v4_v3=flow_test.add_edge(v4, v3);
+  edge_iterator v3_t=flow_test.add_edge(v3, t);
+  edge_iterator v4_t=flow_test.add_edge(v4, t);
+  edge_iterator v3_v3=flow_test.add_edge(v3, v3);
+  edge_iterator s_w=flow_test.add_edge(s, w);
+  //  edge_iterator v2_s=flow_test.add_edge(v2, s);
+  
+
+
+  edge_property_vector<list_graph, int> cap(flow_test);  //serves as length in dijkstra
+  cap.put(s_v1, 16);
+  cap.put(s_v2, 13);
+  cap.put(v1_v2, 10);
+  cap.put(v2_v1, 4);
+  cap.put(v1_v3, 12);
+  cap.put(v3_v2, 9);
+  cap.put(v2_v4, 14);
+  cap.put(v4_v3, 7);
+  cap.put(v3_t, 20);
+  cap.put(v4_t, 4);
+  cap.put(v3_v3, 4);
+  cap.put(s_w, 4);
+  //  cap.put(v2_s, 0);
+
+*/
+
+  //pelda 3, maxflowvalue=4
+  /*      node_iterator s=flow_test.add_node();
+  node_iterator v1=flow_test.add_node();
+  node_iterator v2=flow_test.add_node();
+  node_iterator t=flow_test.add_node();
+  node_iterator w=flow_test.add_node();
+  
+  node_property_vector<list_graph, std::string> node_name(flow_test);
+  node_name.put(s, "s");
+  node_name.put(v1, "v1");
+  node_name.put(v2, "v2");
+  node_name.put(t, "t");
+  node_name.put(w, "w");
+
+  edge_iterator s_v1=flow_test.add_edge(s, v1);
+  edge_iterator v1_v2=flow_test.add_edge(v1, v2);
+  edge_iterator v2_t=flow_test.add_edge(v2, t);
+  edge_iterator v1_v1=flow_test.add_edge(v1, v1);
+  edge_iterator s_w=flow_test.add_edge(s, w);
+
+
+  edge_property_vector<list_graph, int> cap(flow_test); 
+    
+  cap.put(s_v1, 16);
+  cap.put(v1_v2, 10);
+  cap.put(v2_t, 4);
+  cap.put(v1_v1, 3);
+  cap.put(s_w, 5);
+  */
+  
+
+
+  /*
+  std::cout << "Testing reverse_bfs..." << std::endl;
+  
+  reverse_bfs<list_graph> bfs_test(flow_test, t);
+
+  bfs_test.run();
+
+  for (each_node_iterator w=flow_test.first_node(); w.valid(); ++w) {
+    std::cout <<"The distance of " << w << " is " << bfs_test.dist(w) <<std::endl;
+    }
+
+  */
+
+
+
+  std::cout << "Testing preflow_push_hl..." << std::endl;
+  
+  preflow_push_hl<list_graph, int> preflow_push_test(flow_test, s, t, cap);
+
+  preflow_push_test.run();
+
+  std::cout << "Maximum flow value is: " << preflow_push_test.maxflow() << "."<<std::endl;
+
+  std::cout<< "The flow on edge s-v1 is "<< preflow_push_test.flowonedge(s_v1) << "."<<std::endl;
+
+  edge_property_vector<list_graph, int> flow=preflow_push_test.allflow();  
+  for (each_edge_iterator e=flow_test.first_edge(); e.valid(); ++e) {
+    std::cout <<"Flow on edge " << flow_test.tail(e) <<"-" << flow_test.head(e)<< " is " <<flow.get(e) <<std::endl;
+    }
+
+  std::cout << "A minimum cut: " <<std::endl;  
+  node_property_vector<list_graph, bool> mincut=preflow_push_test.mincut();
+
+  for (each_node_iterator v=flow_test.first_node(); v.valid(); ++v) {
+      if (mincut.get(v)) std::cout <<node_name.get(v)<< " ";
+    }
+  
+  std::cout<<"\n\n"<<std::endl;
+
+
+
+
+  std::cout << "Testing preflow_push_max_flow..." << std::endl;
+ 
+  preflow_push_max_flow<list_graph, int> max_flow_test(flow_test, s, t, cap);
+
+  max_flow_test.run();
+
+  std::cout << "Maximum flow value is: " << max_flow_test.maxflow() << "."<< std::endl;
+
+  std::cout << "A minimum cut: " <<std::endl;  
+  node_property_vector<list_graph, bool> mincut2=max_flow_test.mincut();
+
+  for (each_node_iterator v=flow_test.first_node(); v.valid(); ++v) {
+    if (mincut2.get(v)) std::cout <<node_name.get(v)<< " ";
+  }
+  
+  std::cout << std::endl <<std::endl;
+
+
+  /*
+    std::cout << "Testing dijkstra..." << std::endl;
+  
+    node_iterator root=v2;
+
+    dijkstra<list_graph, int> dijkstra_test(flow_test, root, cap);
+
+    dijkstra_test.run();
+
+    for (each_node_iterator w=flow_test.first_node(); w.valid(); ++w) {
+      if (dijkstra_test.reach(w)) {
+      std::cout <<"The distance of " << w << " is " << dijkstra_test.dist(w);
+      if (dijkstra_test.pred(w).valid()) {
+      std::cout <<", a shortest path from the root ends with edge " << dijkstra_test.pred(w) <<std::endl; 
+      } else {
+       std::cout <<", this is the root."<<std::endl; }
+      
+      } else {
+	cout << w << " is not reachable from " << root <<std::endl;
+      }
+    }
+
+  */
+
+  return 0;
+}
+
+
+
+
+
+
+
+
+

Added: hugo/trunk/src/work/jacint/makefile
==============================================================================
--- (empty file)
+++ hugo/trunk/src/work/jacint/makefile	Fri Feb 13 16:12:10 2004
@@ -0,0 +1,5 @@
+BINARIES = flow_test
+
+include ../makefile
+
+CXXFLAGS := $(CXXFLAGS) -I.. -I../../include

Added: hugo/trunk/src/work/jacint/preflow_push_hl.h
==============================================================================
--- (empty file)
+++ hugo/trunk/src/work/jacint/preflow_push_hl.h	Fri Feb 13 16:12:10 2004
@@ -0,0 +1,321 @@
+// -*- C++ -*-
+/*
+preflow_push_hl.hh
+by jacint. 
+Runs the highest label variant of the preflow push algorithm with 
+running time O(n^2\sqrt(m)). 
+
+Member functions:
+
+void run() : runs the algorithm
+
+ The following functions should be used after run() was already run.
+
+T maxflow() : returns the value of a maximum flow
+
+T flowonEdge(Edge_iterator e) : for a fixed maximum flow x it returns x(e) 
+
+EdgeMap<graph_type, T> allflow() : returns the fixed maximum flow x
+
+NodeMap<graph_type, bool> mincut() : returns a 
+     characteristic vector of a minimum cut. (An empty level 
+     in the algorithm gives a minimum cut.)
+*/
+
+#ifndef PREFLOW_PUSH_HL_H
+#define PREFLOW_PUSH_HL_H
+
+#include <algorithm>
+#include <vector>
+#include <stack>
+
+#include <reverse_bfs.hh>
+
+namespace marci {
+
+  template <typename Graph, typename T, typename FlowMap, typename CapacityMap>
+  class preflow_push_hl {
+    
+    typedef typename Graph::NodeIt NodeIt;
+    typedef typename Graph::EdgeIt EdgeIt;
+    typedef typename Graph::EachNodeIt EachNodeIt;
+    typedef typename Graph::OutEdgeIt OutEdgeIt;
+    typedef typename Graph::InEdgeIt InEdgeIt;
+    typedef typename Graph::EachEdgeIt EachEdgeIt;
+    
+
+    Graph& G;
+    NodeIt s;
+    NodeIt t;
+    Graph::EdgeMap<T> flow;
+    Graph::EdgeMap<T> capacity; 
+    T value;
+    Graph::NodeMap<bool> mincutvector;
+
+   
+  public:
+
+    preflow_push_hl(Graph& _G, NodeIt _s, NodeIt _t, 
+		    Graph::EdgeMap<T>& _capacity) :
+      G(_G), s(_s), t(_t), flow(_G, 0), capacity(_capacity), mincutvector(_G, true) { }
+
+
+
+
+    /*
+      The run() function runs the highest label preflow-push, 
+      running time: O(n^2\sqrt(m))
+    */
+    void run() {
+ 
+      Graph::NodeMap<int> level(G);         //level of Node
+      Graph::NodeMap<T> excess(G);          //excess of Node
+            
+      int n=G.nodeNum();                        //number of Nodes 
+      int b=n; 
+      /*b is a bound on the highest level of an active Node. In the beginning it is at most n-2.*/
+
+      std::vector<std::stack<NodeIt> > stack(2*n-1);    //Stack of the active Nodes in level i.
+
+
+
+
+      /*Reverse_bfs from t, to find the starting level.*/
+
+      reverse_bfs<list_graph> bfs(G, t);
+      bfs.run();
+      for(EachNodeIt v=G.template first<EachNodeIt>(); v.valid(); ++v) {
+	level.set(v, bfs.dist(v)); 
+	//std::cout << "the level of " << v << " is " << bfs.dist(v);
+      }
+
+      /*The level of s is fixed to n*/ 
+      level.set(s,n);
+
+
+
+
+
+      /* Starting flow. It is everywhere 0 at the moment. */
+     
+      for(OutEdgeIt i=G.template first<OutEdgeIt>(s); i.valid(); ++i) 
+	{
+	  NodeIt w=G.head(i);
+	  flow.set(i, capacity.get(i)); 
+	  stack[bfs.dist(w)].push(w); 
+	  excess.set(w, capacity.get(i));
+	}
+
+
+      /* 
+	 End of preprocessing 
+      */
+
+
+
+      /*
+	Push/relabel on the highest level active Nodes.
+      */
+	
+      /*While there exists active Node.*/
+      while (b) { 
+
+	/*We decrease the bound if there is no active Node of level b.*/
+	if (stack[b].empty()) {
+	  --b;
+	} else {
+
+	  NodeIt w=stack[b].top();    //w is the highest label active Node.
+	  stack[b].pop();                    //We delete w from the stack.
+	
+	  int newlevel=2*n-2;                   //In newlevel we maintain the next level of w.
+	
+	  for(OutEdgeIt e=G.template first<OutEdgeIt>(w); e.valid(); ++e) {
+	    NodeIt v=G.head(e);
+	    /*e is the Edge wv.*/
+
+	    if (flow.get(e)<capacity.get(e)) {              
+	      /*e is an Edge of the residual graph */
+
+	      if(level.get(w)==level.get(v)+1) {      
+		/*Push is allowed now*/
+
+		if (capacity.get(e)-flow.get(e) > excess.get(w)) {       
+		  /*A nonsaturating push.*/
+		  
+		  if (excess.get(v)==0 && v != s) stack[level.get(v)].push(v); 
+		  /*v becomes active.*/
+		  
+		  flow.set(e, flow.get(e)+excess.get(w));
+		  excess.set(v, excess.get(v)+excess.get(w));
+		  excess.set(w,0);
+		  //std::cout << w << " " << v <<" elore elen nonsat pump "  << std::endl;
+		  break; 
+		} else { 
+		  /*A saturating push.*/
+
+		  if (excess.get(v)==0 && v != s) stack[level.get(v)].push(v); 
+		  /*v becomes active.*/
+
+		  excess.set(v, excess.get(v)+capacity.get(e)-flow.get(e));
+		  excess.set(w, excess.get(w)-capacity.get(e)+flow.get(e));
+		  flow.set(e, capacity.get(e));
+		  //std::cout << w<<" " <<v<<" elore elen sat pump "   << std::endl;
+		  if (excess.get(w)==0) break;
+		  /*If w is not active any more, then we go on to the next Node.*/
+		  
+		} // if (capacity.get(e)-flow.get(e) > excess.get(w))
+	      } // if(level.get(w)==level.get(v)+1)
+	    
+	      else {newlevel = newlevel < level.get(v) ? newlevel : level.get(v);}
+	    
+	    } //if (flow.get(e)<capacity.get(e))
+	 
+	  } //for(OutEdgeIt e=G.first_OutEdge(w); e.valid(); ++e) 
+	  
+
+
+	  for(InEdgeIt e=G.template first<InEdgeIt>(w); e.valid(); ++e) {
+	    NodeIt v=G.tail(e);
+	    /*e is the Edge vw.*/
+
+	    if (excess.get(w)==0) break;
+	    /*It may happen, that w became inactive in the first for cycle.*/		
+	    if(flow.get(e)>0) {             
+	      /*e is an Edge of the residual graph */
+
+	      if(level.get(w)==level.get(v)+1) {  
+		/*Push is allowed now*/
+		
+		if (flow.get(e) > excess.get(w)) { 
+		  /*A nonsaturating push.*/
+		  
+		  if (excess.get(v)==0 && v != s) stack[level.get(v)].push(v); 
+		  /*v becomes active.*/
+
+		  flow.set(e, flow.get(e)-excess.get(w));
+		  excess.set(v, excess.get(v)+excess.get(w));
+		  excess.set(w,0);
+		  //std::cout << v << " " << w << " vissza elen nonsat pump "     << std::endl;
+		  break; 
+		} else {                                               
+		  /*A saturating push.*/
+		  
+		  if (excess.get(v)==0 && v != s) stack[level.get(v)].push(v); 
+		  /*v becomes active.*/
+		  
+		  excess.set(v, excess.get(v)+flow.get(e));
+		  excess.set(w, excess.get(w)-flow.get(e));
+		  flow.set(e,0);
+		  //std::cout << v <<" " << w << " vissza elen sat pump "     << std::endl;
+		  if (excess.get(w)==0) { break;}
+		} //if (flow.get(e) > excess.get(v)) 
+	      } //if(level.get(w)==level.get(v)+1)
+	      
+	      else {newlevel = newlevel < level.get(v) ? newlevel : level.get(v);}
+	      
+
+	    } //if (flow.get(e)>0)
+
+	  } //for
+
+
+	  if (excess.get(w)>0) {
+	    level.set(w,++newlevel);
+	    stack[newlevel].push(w);
+	    b=newlevel;
+	    //std::cout << "The new level of " << w << " is "<< newlevel <<std::endl; 
+	  }
+
+
+	} //else
+       
+      } //while(b)
+
+      value = excess.get(t);
+      /*Max flow value.*/
+
+
+
+
+    } //void run()
+
+
+
+
+
+    /*
+      Returns the maximum value of a flow.
+     */
+
+    T maxflow() {
+      return value;
+    }
+
+
+
+    /*
+      For the maximum flow x found by the algorithm, it returns the flow value on Edge e, i.e. x(e). 
+    */
+
+    T flowonEdge(EdgeIt e) {
+      return flow.get(e);
+    }
+
+
+
+    /*
+      Returns the maximum flow x found by the algorithm.
+    */
+
+    EdgeMap<graph_type, T> allflow() {
+      return flow;
+    }
+
+
+
+    /*
+      Returns a minimum cut by using a reverse bfs from t in the residual graph.
+    */
+    
+    NodeMap<graph_type, bool> mincut() {
+    
+      std::queue<NodeIt> queue;
+      
+      mincutvector.set(t,false);      
+      queue.push(t);
+
+      while (!queue.empty()) {
+        NodeIt w=queue.front();
+	queue.pop();
+
+	for(InEdgeIt e=G.template first<InEdgeIt>(w) ; e.valid(); ++e) {
+	  NodeIt v=G.tail(e);
+	  if (mincutvector.get(v) && flow.get(e) < capacity.get(e) ) {
+	    queue.push(v);
+	    mincutvector.set(v, false);
+	  }
+	} // for
+
+	for(OutEdgeIt e=G.template first<OutEdgeIt>(w) ; e.valid(); ++e) {
+	  NodeIt v=G.head(e);
+	  if (mincutvector.get(v) && flow.get(e) > 0 ) {
+	    queue.push(v);
+	    mincutvector.set(v, false);
+	  }
+	} // for
+
+      }
+
+      return mincutvector;
+    
+    }
+
+
+  };
+}//namespace marci
+#endif 
+
+
+
+



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