COIN-OR::LEMON - Graph Library

source: lemon/test/nagamochi_ibaraki_test.cc @ 1017:5087694945e4

Last change on this file since 1017:5087694945e4 was 1017:5087694945e4, checked in by Balazs Dezso <deba@…>, 9 years ago

New implementation for Nagamochi-Ibaraki algorithm

File size: 3.4 KB
Line 
1/* -*- mode: C++; indent-tabs-mode: nil; -*-
2 *
3 * This file is a part of LEMON, a generic C++ optimization library.
4 *
5 * Copyright (C) 2003-2010
6 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
7 * (Egervary Research Group on Combinatorial Optimization, EGRES).
8 *
9 * Permission to use, modify and distribute this software is granted
10 * provided that this copyright notice appears in all copies. For
11 * precise terms see the accompanying LICENSE file.
12 *
13 * This software is provided "AS IS" with no warranty of any kind,
14 * express or implied, and with no claim as to its suitability for any
15 * purpose.
16 *
17 */
18
19#include <sstream>
20
21#include <lemon/smart_graph.h>
22#include <lemon/adaptors.h>
23#include <lemon/concepts/graph.h>
24#include <lemon/concepts/maps.h>
25#include <lemon/lgf_reader.h>
26#include <lemon/nagamochi_ibaraki.h>
27
28#include "test_tools.h"
29
30using namespace lemon;
31using namespace std;
32
33const std::string lgf =
34  "@nodes\n"
35  "label\n"
36  "0\n"
37  "1\n"
38  "2\n"
39  "3\n"
40  "4\n"
41  "5\n"
42  "@edges\n"
43  "     cap1 cap2 cap3\n"
44  "0 1  1    1    1   \n"
45  "0 2  2    2    4   \n"
46  "1 2  4    4    4   \n"
47  "3 4  1    1    1   \n"
48  "3 5  2    2    4   \n"
49  "4 5  4    4    4   \n"
50  "2 3  1    6    6   \n";
51
52void checkNagamochiIbarakiCompile()
53{
54  typedef int Value;
55  typedef concepts::Graph Graph;
56
57  typedef Graph::Node Node;
58  typedef Graph::Edge Edge;
59  typedef concepts::ReadMap<Edge, Value> CapMap;
60  typedef concepts::WriteMap<Node, bool> CutMap;
61
62  Graph g;
63  Node n;
64  CapMap cap;
65  CutMap cut;
66  Value v;
67  bool b;
68
69  NagamochiIbaraki<Graph, CapMap> ni_test(g, cap);
70  const NagamochiIbaraki<Graph, CapMap>& const_ni_test = ni_test;
71
72  ni_test.init();
73  ni_test.start();
74  b = ni_test.processNextPhase();
75  ni_test.run();
76
77  v = const_ni_test.minCutValue();
78  v = const_ni_test.minCutMap(cut);
79}
80
81template <typename Graph, typename CapMap, typename CutMap>
82typename CapMap::Value
83  cutValue(const Graph& graph, const CapMap& cap, const CutMap& cut)
84{
85  typename CapMap::Value sum = 0;
86  for (typename Graph::EdgeIt e(graph); e != INVALID; ++e) {
87    if (cut[graph.u(e)] != cut[graph.v(e)]) {
88      sum += cap[e];
89    }
90  }
91  return sum;
92}
93
94int main() {
95  SmartGraph graph;
96  SmartGraph::EdgeMap<int> cap1(graph), cap2(graph), cap3(graph);
97  SmartGraph::NodeMap<bool> cut(graph);
98
99  istringstream input(lgf);
100  graphReader(graph, input)
101    .edgeMap("cap1", cap1)
102    .edgeMap("cap2", cap2)
103    .edgeMap("cap3", cap3)
104    .run();
105
106  {
107    NagamochiIbaraki<SmartGraph> ni(graph, cap1);
108    ni.run();
109    ni.minCutMap(cut);
110
111    check(ni.minCutValue() == 1, "Wrong cut value");
112    check(ni.minCutValue() == cutValue(graph, cap1, cut), "Wrong cut value");
113  }
114  {
115    NagamochiIbaraki<SmartGraph> ni(graph, cap2);
116    ni.run();
117    ni.minCutMap(cut);
118
119    check(ni.minCutValue() == 3, "Wrong cut value");
120    check(ni.minCutValue() == cutValue(graph, cap2, cut), "Wrong cut value");
121  }
122  {
123    NagamochiIbaraki<SmartGraph> ni(graph, cap3);
124    ni.run();
125    ni.minCutMap(cut);
126
127    check(ni.minCutValue() == 5, "Wrong cut value");
128    check(ni.minCutValue() == cutValue(graph, cap3, cut), "Wrong cut value");
129  }
130  {
131    NagamochiIbaraki<SmartGraph>::SetUnitCapacity::Create ni(graph);
132    ni.run();
133    ni.minCutMap(cut);
134
135    ConstMap<SmartGraph::Edge, int> cap4(1);
136    check(ni.minCutValue() == 1, "Wrong cut value");
137    check(ni.minCutValue() == cutValue(graph, cap4, cut), "Wrong cut value");
138  }
139
140  return 0;
141}
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