1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/test/preflow_test.cc Mon Sep 13 10:50:28 2004 +0000
1.3 @@ -0,0 +1,166 @@
1.4 +#include <fstream>
1.5 +#include "test_tools.h"
1.6 +#include <hugo/smart_graph.h>
1.7 +#include <hugo/dimacs.h>
1.8 +#include <hugo/preflow.h>
1.9 +#include <hugo/skeletons/graph.h>
1.10 +#include <hugo/skeletons/maps.h>
1.11 +using namespace hugo;
1.12 +
1.13 +void check_Preflow()
1.14 +{
1.15 + typedef int VType;
1.16 + typedef skeleton::StaticGraphSkeleton Graph;
1.17 +
1.18 + typedef Graph::Node Node;
1.19 + typedef Graph::Edge Edge;
1.20 + typedef skeleton::ReadMap<Edge,VType> CapMap;
1.21 + typedef skeleton::ReadWriteMap<Edge,VType> FlowMap;
1.22 + typedef skeleton::ReadWriteMap<Node,bool> CutMap;
1.23 +
1.24 + typedef Preflow<Graph, int, CapMap, FlowMap> PType;
1.25 +
1.26 + Graph G;
1.27 + Node n;
1.28 + CapMap cap;
1.29 + FlowMap flow;
1.30 + CutMap cut;
1.31 +
1.32 + PType preflow_test(G,n,n,cap,flow);
1.33 +
1.34 + preflow_test.run();
1.35 + preflow_test.flowValue();
1.36 + preflow_test.setSource(n);
1.37 + preflow_test.setFlow(flow);
1.38 +
1.39 + preflow_test.phase1(PType::NO_FLOW);
1.40 + preflow_test.minCut(cut);
1.41 +
1.42 + preflow_test.phase2();
1.43 + preflow_test.setTarget(n);
1.44 + preflow_test.setCap(cap);
1.45 + preflow_test.minMinCut(cut);
1.46 + preflow_test.maxMinCut(cut);
1.47 +}
1.48 +
1.49 +int cut_value ( SmartGraph& G, SmartGraph::NodeMap<bool>& cut,
1.50 + SmartGraph::EdgeMap<int>& cap) {
1.51 +
1.52 + int c=0;
1.53 + for(SmartGraph::EdgeIt e(G); e!=INVALID; ++e) {
1.54 + if (cut[G.tail(e)] && !cut[G.head(e)]) c+=cap[e];
1.55 + }
1.56 + return c;
1.57 +}
1.58 +
1.59 +int main() {
1.60 +
1.61 + typedef SmartGraph Graph;
1.62 +
1.63 + typedef Graph::NodeIt NodeIt;
1.64 + typedef Graph::EdgeIt EdgeIt;
1.65 + typedef Graph::EdgeMap<int> CapMap;
1.66 + typedef Graph::EdgeMap<int> FlowMap;
1.67 + typedef Graph::NodeMap<bool> CutMap;
1.68 +
1.69 + typedef Preflow<Graph, int> PType;
1.70 +
1.71 + std::ifstream file("preflow_graph");
1.72 +
1.73 + Graph G;
1.74 + NodeIt s, t;
1.75 + CapMap cap(G);
1.76 + readDimacs(file, G, cap, s, t);
1.77 +
1.78 + FlowMap flow(G,0);
1.79 +
1.80 + PType preflow_test(G, s, t, cap, flow);
1.81 + preflow_test.run(PType::ZERO_FLOW);
1.82 +
1.83 +
1.84 + CutMap mincut(G,false);
1.85 + preflow_test.minCut(mincut);
1.86 + int min_cut_value=cut_value(G,mincut,cap);
1.87 +
1.88 + CutMap minmincut(G,false);
1.89 + preflow_test.minMinCut(minmincut);
1.90 + int min_min_cut_value=cut_value(G,minmincut,cap);
1.91 +
1.92 + CutMap maxmincut(G,false);
1.93 + preflow_test.maxMinCut(maxmincut);
1.94 + int max_min_cut_value=cut_value(G,maxmincut,cap);
1.95 +
1.96 + check(preflow_test.flowValue() == min_cut_value &&
1.97 + min_cut_value == min_min_cut_value &&
1.98 + min_min_cut_value == max_min_cut_value,
1.99 + "The max flow value is not equal to the three min cut values.");
1.100 +
1.101 + int flow_value=preflow_test.flowValue();
1.102 +
1.103 +
1.104 + for(EdgeIt e(G); e!=INVALID; ++e) cap[e]=2*cap[e];
1.105 + preflow_test.setCap(cap);
1.106 + preflow_test.setTarget(++t); //the max flow value remains 2*flow_value
1.107 + //warning: ++t must be a valid node. In preflow_graph, it is.
1.108 +
1.109 + preflow_test.phase1(PType::PRE_FLOW);
1.110 +
1.111 + CutMap mincut1(G,false);
1.112 + preflow_test.minCut(mincut1);
1.113 + min_cut_value=cut_value(G,mincut1,cap);
1.114 +
1.115 + check(preflow_test.flowValue() == min_cut_value &&
1.116 + min_cut_value == 2*flow_value,
1.117 + "The max flow value or the min cut value is wrong.");
1.118 +
1.119 + preflow_test.phase2();
1.120 +
1.121 + CutMap mincut2(G,false);
1.122 + preflow_test.minCut(mincut2);
1.123 + min_cut_value=cut_value(G,mincut2,cap);
1.124 +
1.125 + CutMap minmincut2(G,false);
1.126 + preflow_test.minMinCut(minmincut2);
1.127 + min_min_cut_value=cut_value(G,minmincut2,cap);
1.128 +
1.129 +
1.130 + preflow_test.maxMinCut(maxmincut);
1.131 +
1.132 + max_min_cut_value=cut_value(G,maxmincut,cap);
1.133 +
1.134 + check(preflow_test.flowValue() == min_cut_value &&
1.135 + min_cut_value == min_min_cut_value &&
1.136 + min_min_cut_value == max_min_cut_value &&
1.137 + min_cut_value == 2*flow_value,
1.138 + "The max flow value or the three min cut values were not doubled");
1.139 +
1.140 + EdgeIt e(G);
1.141 + for( int i=1; i==1000; ++i ) {
1.142 + flow[e]=0;
1.143 + ++e;
1.144 + }
1.145 +
1.146 + preflow_test.setFlow(flow);
1.147 + preflow_test.setSource(s);
1.148 +
1.149 + preflow_test.run();
1.150 +
1.151 + CutMap mincut3(G,false);
1.152 + preflow_test.minCut(mincut3);
1.153 + min_cut_value=cut_value(G,mincut3,cap);
1.154 +
1.155 + CutMap minmincut3(G,false);
1.156 + preflow_test.minMinCut(minmincut3);
1.157 + min_min_cut_value=cut_value(G,minmincut3,cap);
1.158 +
1.159 + preflow_test.maxMinCut(maxmincut);
1.160 + max_min_cut_value=cut_value(G,maxmincut,cap);
1.161 +
1.162 + check(preflow_test.flowValue() == min_cut_value &&
1.163 + min_cut_value == min_min_cut_value &&
1.164 + min_min_cut_value == max_min_cut_value,
1.165 + "The max flow value or the three min cut values are incorrect.");
1.166 +}
1.167 +
1.168 +
1.169 +