demo/lgf_demo.cc
changeset 135 6e7aee618f03
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     1 /* -*- C++ -*-
       
     2  *
       
     3  * This file is a part of LEMON, a generic C++ optimization library
       
     4  *
       
     5  * Copyright (C) 2003-2008
       
     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 ///\ingroup demos
       
    20 ///\file
       
    21 ///\brief Demonstrating graph input and output
       
    22 ///
       
    23 /// This simple demo program gives an example of how to read and write
       
    24 /// a graph and additional maps (on the nodes or the edges) from/to a
       
    25 /// stream. 
       
    26 ///
       
    27 /// \include reader_writer_demo.cc
       
    28 
       
    29 #include <iostream>
       
    30 #include <lemon/smart_graph.h>
       
    31 #include <lemon/lgf_reader.h>
       
    32 #include <lemon/lgf_writer.h>
       
    33 #include <lemon/random.h>
       
    34 
       
    35 
       
    36 using namespace lemon;
       
    37 
       
    38 int main(int argc, const char *argv[]) {
       
    39   const int n = argc > 1 ? std::atoi(argv[1]) : 20;
       
    40   const int e = argc > 2 ? std::atoi(argv[2]) : static_cast<int>(n * log(n));
       
    41   const int m = argc > 3 ? std::atoi(argv[3]) : 100;
       
    42 
       
    43   SmartDigraph digraph;
       
    44 
       
    45   std::stringstream ss;
       
    46 
       
    47   try {
       
    48 
       
    49     typedef SmartDigraph Digraph;
       
    50     typedef Digraph::Node Node;
       
    51     typedef Digraph::Arc Arc;
       
    52     typedef Digraph::ArcIt ArcIt;
       
    53 
       
    54     typedef Digraph::NodeMap<int> PotentialMap;
       
    55     typedef Digraph::ArcMap<int> CapacityMap;
       
    56     typedef Digraph::ArcMap<std::string> NameMap;
       
    57 
       
    58     Digraph digraph;
       
    59     PotentialMap potential(digraph);
       
    60     CapacityMap capacity(digraph);
       
    61     NameMap name(digraph);
       
    62 
       
    63     std::vector<Node> nodes;
       
    64     for (int i = 0; i < n; ++i) {
       
    65       Node node = digraph.addNode();
       
    66       potential[node] = rnd[m];
       
    67       nodes.push_back(node);
       
    68     }
       
    69 
       
    70     std::vector<Arc> arcs;
       
    71     for (int i = 0; i < e; ++i) {
       
    72       int s = rnd[n];
       
    73       int t = rnd[n];
       
    74       int c = rnd[m];
       
    75       Arc arc = digraph.addArc(nodes[s], nodes[t]);
       
    76       capacity[arc] = c;
       
    77       std::ostringstream os;
       
    78       os << "arc \t" << i << std::endl;
       
    79       name[arc] = os.str();
       
    80       arcs.push_back(arc);
       
    81     }
       
    82 
       
    83 
       
    84     DigraphWriter<Digraph>(ss, digraph).
       
    85       nodeMap("potential", potential).
       
    86       arcMap("capacity", capacity).
       
    87       arcMap("name", name).
       
    88       node("source", nodes[0]).
       
    89       node("target", nodes[1]).
       
    90       arc("bottleneck", arcs[e / 2]).
       
    91       attribute("creator", "lemon library").
       
    92       run();
       
    93 
       
    94   } catch (DataFormatError& error) {
       
    95     std::cerr << error.what() << std::endl;
       
    96   }
       
    97 
       
    98   try {
       
    99 
       
   100     typedef SmartDigraph Digraph;
       
   101     typedef Digraph::Node Node;
       
   102     typedef Digraph::Arc Arc;
       
   103     typedef Digraph::ArcIt ArcIt;
       
   104 
       
   105     typedef Digraph::NodeMap<int> LabelMap;
       
   106     typedef Digraph::NodeMap<int> PotentialMap;
       
   107     typedef Digraph::ArcMap<int> CapacityMap;
       
   108     typedef Digraph::ArcMap<std::string> NameMap;
       
   109 
       
   110     Digraph digraph;
       
   111     LabelMap label(digraph);
       
   112     PotentialMap potential(digraph);
       
   113     CapacityMap capacity(digraph);
       
   114     NameMap name(digraph);
       
   115 
       
   116     Node s, t;
       
   117     Arc a;
       
   118     
       
   119     std::string creator;
       
   120 
       
   121     for (int i = 0; i < n; ++i) {
       
   122       Node node = digraph.addNode();
       
   123       label[node] = i;
       
   124     }
       
   125     
       
   126     DigraphReader<Digraph>(ss, digraph).
       
   127       useNodes(label).
       
   128       nodeMap("potential", potential).
       
   129       arcMap("capacity", capacity).
       
   130       arcMap("name", name).
       
   131       node("source", s).
       
   132       node("target", t).
       
   133       arc("bottleneck", a).
       
   134       attribute("creator", creator).
       
   135       run();
       
   136 
       
   137     DigraphWriter<Digraph>(std::cout, digraph).
       
   138       nodeMap("potential", potential).
       
   139       arcMap("capacity", capacity).
       
   140       arcMap("name", name).
       
   141       node("source", s).
       
   142       node("target", t).
       
   143       arc("bottleneck", a).
       
   144       attribute("creator", creator).
       
   145       run();
       
   146 
       
   147   } catch (DataFormatError& error) {
       
   148     std::cerr << error.what() << std::endl;
       
   149   }
       
   150 
       
   151 
       
   152   return 0;
       
   153 }