alpar@906: /* -*- C++ -*-
alpar@921:  * src/test/preflow_test.cc - Part of LEMON, a generic C++ optimization library
alpar@906:  *
alpar@906:  * Copyright (C) 2004 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
alpar@906:  * (Egervary Combinatorial Optimization Research Group, EGRES).
alpar@906:  *
alpar@906:  * Permission to use, modify and distribute this software is granted
alpar@906:  * provided that this copyright notice appears in all copies. For
alpar@906:  * precise terms see the accompanying LICENSE file.
alpar@906:  *
alpar@906:  * This software is provided "AS IS" with no warranty of any kind,
alpar@906:  * express or implied, and with no claim as to its suitability for any
alpar@906:  * purpose.
alpar@906:  *
alpar@906:  */
alpar@906: 
jacint@833: #include <fstream>
klao@858: #include <string>
klao@858: 
jacint@833: #include "test_tools.h"
alpar@921: #include <lemon/smart_graph.h>
alpar@921: #include <lemon/dimacs.h>
alpar@921: #include <lemon/preflow.h>
alpar@921: #include <lemon/skeletons/graph.h>
alpar@921: #include <lemon/skeletons/maps.h>
alpar@855: 
alpar@921: using namespace lemon;
jacint@833: 
jacint@833: void check_Preflow() 
jacint@833: {
jacint@833:   typedef int VType;
alpar@880:   typedef skeleton::StaticGraph Graph;
jacint@833: 
jacint@833:   typedef Graph::Node Node;
jacint@833:   typedef Graph::Edge Edge;
jacint@833:   typedef skeleton::ReadMap<Edge,VType> CapMap;
jacint@833:   typedef skeleton::ReadWriteMap<Edge,VType> FlowMap;
jacint@833:   typedef skeleton::ReadWriteMap<Node,bool> CutMap;
jacint@833:  
jacint@833:   typedef Preflow<Graph, int, CapMap, FlowMap> PType;
jacint@833: 
marci@940:   Graph g;
jacint@833:   Node n;
jacint@833:   CapMap cap;
jacint@833:   FlowMap flow;
jacint@833:   CutMap cut;
jacint@833: 
marci@940:   PType preflow_test(g,n,n,cap,flow);
jacint@833: 
jacint@833:   preflow_test.run();
jacint@833:   preflow_test.flowValue();
jacint@833:   preflow_test.setSource(n);
jacint@833:   preflow_test.setFlow(flow);
jacint@833: 
jacint@833:   preflow_test.phase1(PType::NO_FLOW);
jacint@833:   preflow_test.minCut(cut);
jacint@833: 
jacint@833:   preflow_test.phase2();
jacint@833:   preflow_test.setTarget(n);
jacint@833:   preflow_test.setCap(cap);
jacint@833:   preflow_test.minMinCut(cut);
jacint@833:   preflow_test.maxMinCut(cut);
jacint@833: }
jacint@833: 
marci@940: int cut_value ( SmartGraph& g, SmartGraph::NodeMap<bool>& cut, 
jacint@833: 		SmartGraph::EdgeMap<int>& cap) {
jacint@833:   
jacint@833:   int c=0;
marci@940:   for(SmartGraph::EdgeIt e(g); e!=INVALID; ++e) {
marci@940:     if (cut[g.tail(e)] && !cut[g.head(e)]) c+=cap[e];
jacint@833:   }
jacint@833:   return c;
jacint@833: }
jacint@833: 
jacint@833: int main() {
jacint@833: 
jacint@833:   typedef SmartGraph Graph;
jacint@833:   
alpar@842:   typedef Graph::Node Node;
jacint@833:   typedef Graph::NodeIt NodeIt;
jacint@833:   typedef Graph::EdgeIt EdgeIt;
jacint@833:   typedef Graph::EdgeMap<int> CapMap;
jacint@833:   typedef Graph::EdgeMap<int> FlowMap;
jacint@833:   typedef Graph::NodeMap<bool> CutMap;
jacint@833: 
jacint@833:   typedef Preflow<Graph, int> PType;
jacint@833: 
klao@859:   std::string f_name;
klao@858:   if( getenv("srcdir") ) {
jacint@887:     f_name = std::string(getenv("srcdir")) + "/preflow_graph.dim";
klao@858:   }
klao@858:   else {
jacint@887:     f_name = "preflow_graph.dim";
klao@858:   }
alpar@855:   
klao@858:   std::ifstream file(f_name.c_str());
alpar@855:   
klao@858:   check(file, "Input file '" << f_name << "' not found.");
jacint@833:   
marci@940:   Graph g;
alpar@842:   Node s, t;
marci@940:   CapMap cap(g);
marci@940:   readDimacs(file, g, cap, s, t);
jacint@833: 
marci@940:   FlowMap flow(g,0);
jacint@887: 
jacint@833:  
jacint@887: 
marci@940:   PType preflow_test(g, s, t, cap, flow);
jacint@833:   preflow_test.run(PType::ZERO_FLOW);
jacint@887:     
marci@940:   CutMap min_cut(g,false);
marci@940:   preflow_test.minCut(min_cut); 
marci@940:   int min_cut_value=cut_value(g,min_cut,cap);
jacint@833:    
marci@940:   CutMap min_min_cut(g,false);
marci@940:   preflow_test.minMinCut(min_min_cut); 
marci@940:   int min_min_cut_value=cut_value(g,min_min_cut,cap);
jacint@833:    
marci@940:   CutMap max_min_cut(g,false);
marci@940:   preflow_test.maxMinCut(max_min_cut); 
marci@940:   int max_min_cut_value=cut_value(g,max_min_cut,cap);
jacint@833: 
jacint@833:   check(preflow_test.flowValue() == min_cut_value &&
jacint@833: 	min_cut_value == min_min_cut_value &&
jacint@833: 	min_min_cut_value == max_min_cut_value,
jacint@833: 	"The max flow value is not equal to the three min cut values.");
jacint@833: 
jacint@833:   int flow_value=preflow_test.flowValue();
jacint@833: 
jacint@833: 
jacint@887: 
marci@940:   for(EdgeIt e(g); e!=INVALID; ++e) cap[e]=2*cap[e]; 
jacint@833:   preflow_test.setCap(cap);  
alpar@842: 
jacint@833:   preflow_test.phase1(PType::PRE_FLOW);
jacint@833: 
marci@940:   CutMap min_cut1(g,false);
marci@940:   preflow_test.minCut(min_cut1); 
marci@940:   min_cut_value=cut_value(g,min_cut1,cap);
jacint@833:    
jacint@833:   check(preflow_test.flowValue() == min_cut_value &&
jacint@833: 	min_cut_value == 2*flow_value,
jacint@833: 	"The max flow value or the min cut value is wrong.");
jacint@833: 
jacint@833:   preflow_test.phase2();
jacint@833: 
marci@940:   CutMap min_cut2(g,false);
marci@940:   preflow_test.minCut(min_cut2); 
marci@940:   min_cut_value=cut_value(g,min_cut2,cap);
jacint@833:    
marci@940:   CutMap min_min_cut2(g,false);
marci@940:   preflow_test.minMinCut(min_min_cut2); 
marci@940:   min_min_cut_value=cut_value(g,min_min_cut2,cap);
jacint@833:  
marci@940:   preflow_test.maxMinCut(max_min_cut); 
marci@940:   max_min_cut_value=cut_value(g,max_min_cut,cap);
jacint@833: 
jacint@833:   check(preflow_test.flowValue() == min_cut_value &&
jacint@833: 	min_cut_value == min_min_cut_value &&
jacint@833: 	min_min_cut_value == max_min_cut_value &&
jacint@833: 	min_cut_value == 2*flow_value,
jacint@833: 	"The max flow value or the three min cut values were not doubled");
jacint@833: 
jacint@887: 
jacint@887: 
marci@940:   EdgeIt e(g);
jacint@887:   for( int i=1; i==10; ++i ) {
jacint@887:     flow.set(e,0);
jacint@833:     ++e;
jacint@833:   }
jacint@833: 
jacint@833:   preflow_test.setFlow(flow); 
jacint@887: 
marci@940:   NodeIt tmp1(g,s);
jacint@887:   ++tmp1;
jacint@887:   if ( tmp1 != INVALID ) s=tmp1;
jacint@887: 
marci@940:   NodeIt tmp2(g,t);
jacint@887:   ++tmp2;
jacint@887:   if ( tmp2 != INVALID ) t=tmp2;
jacint@887: 
jacint@833:   preflow_test.setSource(s);
jacint@887:   preflow_test.setTarget(t); 
jacint@887:   
jacint@833:   preflow_test.run();
jacint@833: 
marci@940:   CutMap min_cut3(g,false);
marci@940:   preflow_test.minCut(min_cut3); 
marci@940:   min_cut_value=cut_value(g,min_cut3,cap);
jacint@833:    
marci@940:   CutMap min_min_cut3(g,false);
marci@940:   preflow_test.minMinCut(min_min_cut3); 
marci@940:   min_min_cut_value=cut_value(g,min_min_cut3,cap);
jacint@833:    
marci@940:   preflow_test.maxMinCut(max_min_cut); 
marci@940:   max_min_cut_value=cut_value(g,max_min_cut,cap);
jacint@833: 
jacint@833:   check(preflow_test.flowValue() == min_cut_value &&
jacint@833: 	min_cut_value == min_min_cut_value &&
jacint@833: 	min_min_cut_value == max_min_cut_value,
jacint@833: 	"The max flow value or the three min cut values are incorrect.");
jacint@833: }