lemon/dimacs.h
author ladanyi
Sun, 02 Mar 2008 22:55:27 +0000
changeset 2592 f1fb0c31f952
parent 2455 dc3f7991ad58
permissions -rw-r--r--
Revert to long long int since currently I don't know a better solution.
     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 #ifndef LEMON_DIMACS_H
    20 #define LEMON_DIMACS_H
    21 
    22 #include <iostream>
    23 #include <string>
    24 #include <vector>
    25 #include <lemon/maps.h>
    26 #include <lemon/bits/invalid.h>
    27 
    28 /// \ingroup dimacs_group
    29 /// \file
    30 /// \brief DIMACS file format reader.
    31 
    32 namespace lemon {
    33 
    34   ///@defgroup dimacs_group DIMACS format
    35   ///\brief Read and write files in DIMACS format
    36   ///
    37   ///Tools to read a graph from or write it to a file in DIMACS format
    38   ///data
    39   ///\ingroup io_group
    40 
    41   /// \addtogroup dimacs_group
    42   /// @{
    43   
    44   /// DIMACS min cost flow reader function.
    45   ///
    46   /// This function reads a min cost flow instance from DIMACS format,
    47   /// i.e. from DIMACS files having a line starting with
    48   /// \code
    49   ///   p min
    50   /// \endcode
    51   /// At the beginning \c g is cleared by \c g.clear(). The supply 
    52   /// amount of the nodes are written to \c supply (signed). The 
    53   /// lower bounds, capacities and costs of the edges are written to 
    54   /// \c lower, \c capacity and \c cost.
    55   ///
    56   /// \author Marton Makai and Peter Kovacs
    57   template <typename Graph, typename LowerMap, 
    58     typename CapacityMap, typename CostMap, 
    59     typename SupplyMap>
    60   void readDimacs( std::istream& is,
    61 		   Graph &g,
    62 		   LowerMap& lower, 
    63 		   CapacityMap& capacity, 
    64 		   CostMap& cost,
    65 		   SupplyMap& supply )
    66   {
    67     g.clear();
    68     std::vector<typename Graph::Node> nodes;
    69     typename Graph::Edge e;
    70     std::string problem, str;
    71     char c;
    72     int n, m; 
    73     int i, j;
    74     typename SupplyMap::Value sup;
    75     typename CapacityMap::Value low;
    76     typename CapacityMap::Value cap;
    77     typename CostMap::Value co;
    78     while (is >> c) {
    79       switch (c) {
    80       case 'c': // comment line
    81 	getline(is, str);
    82 	break;
    83       case 'p': // problem definition line
    84 	is >> problem >> n >> m;
    85 	getline(is, str);
    86 	if (problem != "min") return;
    87 	nodes.resize(n + 1);
    88 	for (int k = 1; k <= n; ++k) {
    89 	  nodes[k] = g.addNode();
    90 	  supply.set(nodes[k], 0);
    91 	}
    92 	break;
    93       case 'n': // node definition line
    94 	is >> i >> sup;
    95 	getline(is, str);
    96 	supply.set(nodes[i], sup);
    97 	break;
    98       case 'a': // edge (arc) definition line
    99 	is >> i >> j >> low >> cap >> co;
   100 	getline(is, str);
   101 	e = g.addEdge(nodes[i], nodes[j]);
   102 	lower.set(e, low);
   103 	if (cap >= 0)
   104 	  capacity.set(e, cap);
   105 	else
   106 	  capacity.set(e, -1);
   107 	cost.set(e, co);
   108 	break;
   109       }
   110     }
   111   }
   112 
   113   /// DIMACS max flow reader function.
   114   ///
   115   /// This function reads a max flow instance from DIMACS format,
   116   /// i.e. from DIMACS files having a line starting with
   117   /// \code
   118   ///   p max
   119   /// \endcode
   120   /// At the beginning \c g is cleared by \c g.clear(). The edge 
   121   /// capacities are written to \c capacity and \c s and \c t are
   122   /// set to the source and the target nodes.
   123   ///
   124   /// \author Marton Makai
   125   template<typename Graph, typename CapacityMap>
   126   void readDimacs(std::istream& is, Graph &g, CapacityMap& capacity, 
   127 		  typename Graph::Node &s, typename Graph::Node &t) {
   128     g.clear();
   129     std::vector<typename Graph::Node> nodes;
   130     typename Graph::Edge e;
   131     std::string problem;
   132     char c, d;
   133     int n, m; 
   134     int i, j;
   135     typename CapacityMap::Value _cap;
   136     std::string str;
   137     while (is >> c) {
   138       switch (c) {
   139       case 'c': // comment line
   140 	getline(is, str);
   141 	break;
   142       case 'p': // problem definition line
   143 	is >> problem >> n >> m;
   144 	getline(is, str);
   145 	nodes.resize(n + 1);
   146 	for (int k = 1; k <= n; ++k)
   147 	  nodes[k] = g.addNode();
   148 	break;
   149       case 'n': // node definition line
   150 	if (problem == "sp") { // shortest path problem
   151 	  is >> i;
   152 	  getline(is, str);
   153 	  s = nodes[i];
   154 	}
   155 	if (problem == "max") { // max flow problem
   156 	  is >> i >> d;
   157 	  getline(is, str);
   158 	  if (d == 's') s = nodes[i];
   159 	  if (d == 't') t = nodes[i];
   160 	}
   161 	break;
   162       case 'a': // edge (arc) definition line
   163 	if (problem == "max" || problem == "sp") {
   164 	  is >> i >> j >> _cap;
   165 	  getline(is, str);
   166 	  e = g.addEdge(nodes[i], nodes[j]);
   167 	  capacity.set(e, _cap);
   168 	} else {
   169 	  is >> i >> j;
   170 	  getline(is, str);
   171 	  g.addEdge(nodes[i], nodes[j]);
   172 	}
   173 	break;
   174       }
   175     }
   176   }
   177 
   178   /// DIMACS shortest path reader function.
   179   ///
   180   /// This function reads a shortest path instance from DIMACS format,
   181   /// i.e. from DIMACS files having a line starting with
   182   /// \code
   183   ///   p sp
   184   /// \endcode
   185   /// At the beginning \c g is cleared by \c g.clear(). The edge
   186   /// capacities are written to \c capacity and \c s is set to the
   187   /// source node.
   188   ///
   189   /// \author Marton Makai
   190   template<typename Graph, typename CapacityMap>
   191   void readDimacs(std::istream& is, Graph &g, CapacityMap& capacity, 
   192 		  typename Graph::Node &s) {
   193     readDimacs(is, g, capacity, s, s);
   194   }
   195 
   196   /// DIMACS capacitated graph reader function.
   197   ///
   198   /// This function reads an edge capacitated graph instance from
   199   /// DIMACS format. At the beginning \c g is cleared by \c g.clear()
   200   /// and the edge capacities are written to \c capacity.
   201   ///
   202   /// \author Marton Makai
   203   template<typename Graph, typename CapacityMap>
   204   void readDimacs(std::istream& is, Graph &g, CapacityMap& capacity) {
   205     typename Graph::Node u;
   206     readDimacs(is, g, capacity, u, u);
   207   }
   208 
   209   /// DIMACS plain graph reader function.
   210   ///
   211   /// This function reads a graph without any designated nodes and
   212   /// maps from DIMACS format, i.e. from DIMACS files having a line
   213   /// starting with
   214   /// \code
   215   ///   p mat
   216   /// \endcode
   217   /// At the beginning \c g is cleared by \c g.clear().
   218   ///
   219   /// \author Marton Makai
   220   template<typename Graph>
   221   void readDimacs(std::istream& is, Graph &g) {
   222     typename Graph::Node u;
   223     NullMap<typename Graph::Edge, int> n;
   224     readDimacs(is, g, n, u, u);
   225   }
   226   
   227   /// DIMACS plain graph writer function.
   228   ///
   229   /// This function writes a graph without any designated nodes and
   230   /// maps into DIMACS format, i.e. into DIMACS file having a line 
   231   /// starting with
   232   /// \code
   233   ///   p mat
   234   /// \endcode
   235   ///
   236   /// \author Marton Makai
   237   template<typename Graph>
   238   void writeDimacs(std::ostream& os, const Graph &g) {
   239     typedef typename Graph::NodeIt NodeIt;
   240     typedef typename Graph::EdgeIt EdgeIt;  
   241     
   242     os << "c matching problem" << std::endl;
   243     os << "p mat " << g.nodeNum() << " " << g.edgeNum() << std::endl;
   244 
   245     typename Graph::template NodeMap<int> nodes(g);
   246     int i = 1;
   247     for(NodeIt v(g); v != INVALID; ++v) {
   248       nodes.set(v, i);
   249       ++i;
   250     }    
   251     for(EdgeIt e(g); e != INVALID; ++e) {
   252       os << "a " << nodes[g.source(e)] << " " << nodes[g.target(e)] << std::endl; 
   253     }
   254   }
   255 
   256   /// @}
   257 
   258 } //namespace lemon
   259 
   260 #endif //LEMON_DIMACS_H