alpar@385: /* -*- mode: C++; indent-tabs-mode: nil; -*-
alpar@385:  *
alpar@385:  * This file is a part of LEMON, a generic C++ optimization library.
alpar@385:  *
alpar@440:  * Copyright (C) 2003-2009
alpar@385:  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
alpar@385:  * (Egervary Research Group on Combinatorial Optimization, EGRES).
alpar@385:  *
alpar@385:  * Permission to use, modify and distribute this software is granted
alpar@385:  * provided that this copyright notice appears in all copies. For
alpar@385:  * precise terms see the accompanying LICENSE file.
alpar@385:  *
alpar@385:  * This software is provided "AS IS" with no warranty of any kind,
alpar@385:  * express or implied, and with no claim as to its suitability for any
alpar@385:  * purpose.
alpar@385:  *
alpar@385:  */
alpar@385: 
alpar@385: #ifndef LEMON_DIMACS_H
alpar@385: #define LEMON_DIMACS_H
alpar@385: 
alpar@385: #include <iostream>
alpar@385: #include <string>
alpar@385: #include <vector>
alpar@561: #include <limits>
alpar@385: #include <lemon/maps.h>
alpar@387: #include <lemon/error.h>
alpar@385: /// \ingroup dimacs_group
alpar@385: /// \file
alpar@385: /// \brief DIMACS file format reader.
alpar@385: 
alpar@385: namespace lemon {
alpar@385: 
alpar@385:   /// \addtogroup dimacs_group
alpar@385:   /// @{
alpar@385: 
alpar@387:   /// DIMACS file type descriptor.
alpar@387:   struct DimacsDescriptor
alpar@387:   {
kpeter@584:     ///\brief DIMACS file type enum
kpeter@584:     ///
kpeter@584:     ///DIMACS file type enum.
kpeter@584:     enum Type {
kpeter@584:       NONE,  ///< Undefined type.
kpeter@584:       MIN,   ///< DIMACS file type for minimum cost flow problems.
kpeter@584:       MAX,   ///< DIMACS file type for maximum flow problems.
kpeter@584:       SP,    ///< DIMACS file type for shostest path problems.
kpeter@584:       MAT    ///< DIMACS file type for plain graphs and matching problems.
kpeter@584:     };
alpar@387:     ///The file type
alpar@387:     Type type;
kpeter@388:     ///The number of nodes in the graph
alpar@387:     int nodeNum;
kpeter@388:     ///The number of edges in the graph
alpar@387:     int edgeNum;
alpar@387:     int lineShift;
kpeter@584:     ///Constructor. It sets the type to \c NONE.
alpar@387:     DimacsDescriptor() : type(NONE) {}
alpar@387:   };
alpar@387: 
alpar@387:   ///Discover the type of a DIMACS file
alpar@387: 
kpeter@584:   ///This function starts seeking the beginning of the given file for the
kpeter@584:   ///problem type and size info. 
kpeter@584:   ///The found data is returned in a special struct that can be evaluated
kpeter@584:   ///and passed to the appropriate reader function.
alpar@387:   DimacsDescriptor dimacsType(std::istream& is)
alpar@387:   {
alpar@387:     DimacsDescriptor r;
alpar@387:     std::string problem,str;
alpar@387:     char c;
alpar@387:     r.lineShift=0;
alpar@387:     while (is >> c)
alpar@387:       switch(c)
alpar@387:         {
alpar@387:         case 'p':
alpar@387:           if(is >> problem >> r.nodeNum >> r.edgeNum)
alpar@387:             {
alpar@387:               getline(is, str);
alpar@387:               r.lineShift++;
alpar@387:               if(problem=="min") r.type=DimacsDescriptor::MIN;
alpar@387:               else if(problem=="max") r.type=DimacsDescriptor::MAX;
alpar@387:               else if(problem=="sp") r.type=DimacsDescriptor::SP;
alpar@387:               else if(problem=="mat") r.type=DimacsDescriptor::MAT;
alpar@387:               else throw FormatError("Unknown problem type");
alpar@387:               return r;
alpar@387:             }
alpar@387:           else
alpar@387:             {
alpar@387:               throw FormatError("Missing or wrong problem type declaration.");
alpar@387:             }
alpar@387:           break;
alpar@387:         case 'c':
alpar@387:           getline(is, str);
alpar@387:           r.lineShift++;
alpar@387:           break;
alpar@387:         default:
alpar@387:           throw FormatError("Unknown DIMACS declaration.");
alpar@387:         }
alpar@387:     throw FormatError("Missing problem type declaration.");
alpar@387:   }
alpar@387: 
alpar@387: 
kpeter@584:   /// \brief DIMACS minimum cost flow reader function.
alpar@385:   ///
kpeter@388:   /// This function reads a minimum cost flow instance from DIMACS format,
kpeter@388:   /// i.e. from a DIMACS file having a line starting with
alpar@385:   /// \code
alpar@385:   ///   p min
alpar@385:   /// \endcode
alpar@387:   /// At the beginning, \c g is cleared by \c g.clear(). The supply
alpar@561:   /// amount of the nodes are written to the \c supply node map
alpar@561:   /// (they are signed values). The lower bounds, capacities and costs
alpar@561:   /// of the arcs are written to the \c lower, \c capacity and \c cost
alpar@561:   /// arc maps.
alpar@561:   ///
alpar@561:   /// If the capacity of an arc is less than the lower bound, it will
alpar@561:   /// be set to "infinite" instead. The actual value of "infinite" is
alpar@561:   /// contolled by the \c infty parameter. If it is 0 (the default value),
alpar@561:   /// \c std::numeric_limits<Capacity>::infinity() will be used if available,
alpar@561:   /// \c std::numeric_limits<Capacity>::max() otherwise. If \c infty is set to
alpar@561:   /// a non-zero value, that value will be used as "infinite".
alpar@387:   ///
alpar@387:   /// If the file type was previously evaluated by dimacsType(), then
alpar@387:   /// the descriptor struct should be given by the \c dest parameter.
alpar@385:   template <typename Digraph, typename LowerMap,
alpar@387:             typename CapacityMap, typename CostMap,
alpar@387:             typename SupplyMap>
alpar@387:   void readDimacsMin(std::istream& is,
alpar@387:                      Digraph &g,
alpar@387:                      LowerMap& lower,
alpar@387:                      CapacityMap& capacity,
alpar@387:                      CostMap& cost,
alpar@387:                      SupplyMap& supply,
alpar@561:                      typename CapacityMap::Value infty = 0,
alpar@387:                      DimacsDescriptor desc=DimacsDescriptor())
alpar@385:   {
alpar@385:     g.clear();
alpar@385:     std::vector<typename Digraph::Node> nodes;
alpar@385:     typename Digraph::Arc e;
alpar@385:     std::string problem, str;
alpar@385:     char c;
alpar@385:     int i, j;
alpar@387:     if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
alpar@387:     if(desc.type!=DimacsDescriptor::MIN)
alpar@387:       throw FormatError("Problem type mismatch");
alpar@387: 
alpar@387:     nodes.resize(desc.nodeNum + 1);
alpar@387:     for (int k = 1; k <= desc.nodeNum; ++k) {
alpar@387:       nodes[k] = g.addNode();
alpar@387:       supply.set(nodes[k], 0);
alpar@387:     }
alpar@387: 
alpar@385:     typename SupplyMap::Value sup;
alpar@385:     typename CapacityMap::Value low;
alpar@385:     typename CapacityMap::Value cap;
alpar@385:     typename CostMap::Value co;
alpar@561:     typedef typename CapacityMap::Value Capacity;
alpar@561:     if(infty==0)
alpar@561:       infty = std::numeric_limits<Capacity>::has_infinity ?
alpar@561:         std::numeric_limits<Capacity>::infinity() :
alpar@561:         std::numeric_limits<Capacity>::max();
alpar@561: 
alpar@385:     while (is >> c) {
alpar@385:       switch (c) {
alpar@385:       case 'c': // comment line
alpar@385:         getline(is, str);
alpar@385:         break;
alpar@385:       case 'n': // node definition line
alpar@385:         is >> i >> sup;
alpar@385:         getline(is, str);
alpar@385:         supply.set(nodes[i], sup);
alpar@385:         break;
alpar@561:       case 'a': // arc definition line
alpar@385:         is >> i >> j >> low >> cap >> co;
alpar@385:         getline(is, str);
alpar@385:         e = g.addArc(nodes[i], nodes[j]);
alpar@385:         lower.set(e, low);
alpar@561:         if (cap >= low)
alpar@385:           capacity.set(e, cap);
alpar@385:         else
alpar@561:           capacity.set(e, infty);
alpar@385:         cost.set(e, co);
alpar@385:         break;
alpar@385:       }
alpar@385:     }
alpar@385:   }
alpar@385: 
alpar@385:   template<typename Digraph, typename CapacityMap>
alpar@387:   void _readDimacs(std::istream& is,
alpar@387:                    Digraph &g,
alpar@387:                    CapacityMap& capacity,
alpar@387:                    typename Digraph::Node &s,
alpar@387:                    typename Digraph::Node &t,
alpar@561:                    typename CapacityMap::Value infty = 0,
alpar@387:                    DimacsDescriptor desc=DimacsDescriptor()) {
alpar@385:     g.clear();
alpar@387:     s=t=INVALID;
alpar@385:     std::vector<typename Digraph::Node> nodes;
alpar@385:     typename Digraph::Arc e;
alpar@385:     char c, d;
alpar@385:     int i, j;
alpar@385:     typename CapacityMap::Value _cap;
alpar@385:     std::string str;
alpar@387:     nodes.resize(desc.nodeNum + 1);
alpar@387:     for (int k = 1; k <= desc.nodeNum; ++k) {
alpar@387:       nodes[k] = g.addNode();
alpar@387:     }
alpar@561:     typedef typename CapacityMap::Value Capacity;
alpar@387: 
alpar@561:     if(infty==0)
alpar@561:       infty = std::numeric_limits<Capacity>::has_infinity ?
alpar@561:         std::numeric_limits<Capacity>::infinity() :
alpar@561:         std::numeric_limits<Capacity>::max();
alpar@561:  
alpar@385:     while (is >> c) {
alpar@385:       switch (c) {
alpar@385:       case 'c': // comment line
alpar@385:         getline(is, str);
alpar@385:         break;
alpar@385:       case 'n': // node definition line
alpar@387:         if (desc.type==DimacsDescriptor::SP) { // shortest path problem
alpar@385:           is >> i;
alpar@385:           getline(is, str);
alpar@385:           s = nodes[i];
alpar@385:         }
alpar@387:         if (desc.type==DimacsDescriptor::MAX) { // max flow problem
alpar@385:           is >> i >> d;
alpar@385:           getline(is, str);
alpar@385:           if (d == 's') s = nodes[i];
alpar@385:           if (d == 't') t = nodes[i];
alpar@385:         }
alpar@385:         break;
alpar@561:       case 'a': // arc definition line
alpar@561:         if (desc.type==DimacsDescriptor::SP) {
alpar@385:           is >> i >> j >> _cap;
alpar@385:           getline(is, str);
alpar@385:           e = g.addArc(nodes[i], nodes[j]);
alpar@385:           capacity.set(e, _cap);
alpar@561:         } 
alpar@561:         else if (desc.type==DimacsDescriptor::MAX) {
alpar@561:           is >> i >> j >> _cap;
alpar@561:           getline(is, str);
alpar@561:           e = g.addArc(nodes[i], nodes[j]);
alpar@561:           if (_cap >= 0)
alpar@561:             capacity.set(e, _cap);
alpar@561:           else
alpar@561:             capacity.set(e, infty);
alpar@561:         }
alpar@561:         else {
alpar@385:           is >> i >> j;
alpar@385:           getline(is, str);
alpar@385:           g.addArc(nodes[i], nodes[j]);
alpar@385:         }
alpar@385:         break;
alpar@385:       }
alpar@385:     }
alpar@385:   }
alpar@385: 
kpeter@584:   /// \brief DIMACS maximum flow reader function.
alpar@387:   ///
kpeter@388:   /// This function reads a maximum flow instance from DIMACS format,
kpeter@388:   /// i.e. from a DIMACS file having a line starting with
alpar@387:   /// \code
alpar@387:   ///   p max
alpar@387:   /// \endcode
alpar@387:   /// At the beginning, \c g is cleared by \c g.clear(). The arc
alpar@561:   /// capacities are written to the \c capacity arc map and \c s and
alpar@561:   /// \c t are set to the source and the target nodes.
alpar@561:   ///
alpar@561:   /// If the capacity of an arc is negative, it will
alpar@561:   /// be set to "infinite" instead. The actual value of "infinite" is
alpar@561:   /// contolled by the \c infty parameter. If it is 0 (the default value),
alpar@561:   /// \c std::numeric_limits<Capacity>::infinity() will be used if available,
alpar@561:   /// \c std::numeric_limits<Capacity>::max() otherwise. If \c infty is set to
alpar@561:   /// a non-zero value, that value will be used as "infinite".
alpar@387:   ///
alpar@387:   /// If the file type was previously evaluated by dimacsType(), then
alpar@387:   /// the descriptor struct should be given by the \c dest parameter.
alpar@387:   template<typename Digraph, typename CapacityMap>
alpar@387:   void readDimacsMax(std::istream& is,
alpar@387:                      Digraph &g,
alpar@387:                      CapacityMap& capacity,
alpar@387:                      typename Digraph::Node &s,
alpar@387:                      typename Digraph::Node &t,
alpar@561:                      typename CapacityMap::Value infty = 0,
alpar@387:                      DimacsDescriptor desc=DimacsDescriptor()) {
alpar@387:     if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
alpar@387:     if(desc.type!=DimacsDescriptor::MAX)
alpar@387:       throw FormatError("Problem type mismatch");
alpar@561:     _readDimacs(is,g,capacity,s,t,infty,desc);
alpar@387:   }
alpar@387: 
kpeter@584:   /// \brief DIMACS shortest path reader function.
alpar@385:   ///
alpar@385:   /// This function reads a shortest path instance from DIMACS format,
kpeter@388:   /// i.e. from a DIMACS file having a line starting with
alpar@385:   /// \code
alpar@385:   ///   p sp
alpar@385:   /// \endcode
alpar@387:   /// At the beginning, \c g is cleared by \c g.clear(). The arc
alpar@561:   /// lengths are written to the \c length arc map and \c s is set to the
alpar@385:   /// source node.
alpar@387:   ///
alpar@387:   /// If the file type was previously evaluated by dimacsType(), then
alpar@387:   /// the descriptor struct should be given by the \c dest parameter.
alpar@387:   template<typename Digraph, typename LengthMap>
alpar@387:   void readDimacsSp(std::istream& is,
alpar@387:                     Digraph &g,
alpar@387:                     LengthMap& length,
alpar@387:                     typename Digraph::Node &s,
alpar@387:                     DimacsDescriptor desc=DimacsDescriptor()) {
alpar@386:     typename Digraph::Node t;
alpar@387:     if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
alpar@387:     if(desc.type!=DimacsDescriptor::SP)
alpar@387:       throw FormatError("Problem type mismatch");
alpar@561:     _readDimacs(is, g, length, s, t, 0, desc);
alpar@385:   }
alpar@385: 
kpeter@584:   /// \brief DIMACS capacitated digraph reader function.
alpar@385:   ///
alpar@385:   /// This function reads an arc capacitated digraph instance from
alpar@561:   /// DIMACS 'max' or 'sp' format.
alpar@387:   /// At the beginning, \c g is cleared by \c g.clear()
alpar@561:   /// and the arc capacities/lengths are written to the \c capacity
alpar@561:   /// arc map.
alpar@561:   ///
alpar@561:   /// In case of the 'max' format, if the capacity of an arc is negative,
alpar@561:   /// it will
alpar@561:   /// be set to "infinite" instead. The actual value of "infinite" is
alpar@561:   /// contolled by the \c infty parameter. If it is 0 (the default value),
alpar@561:   /// \c std::numeric_limits<Capacity>::infinity() will be used if available,
alpar@561:   /// \c std::numeric_limits<Capacity>::max() otherwise. If \c infty is set to
alpar@561:   /// a non-zero value, that value will be used as "infinite".
alpar@387:   ///
alpar@387:   /// If the file type was previously evaluated by dimacsType(), then
alpar@387:   /// the descriptor struct should be given by the \c dest parameter.
alpar@385:   template<typename Digraph, typename CapacityMap>
alpar@387:   void readDimacsCap(std::istream& is,
alpar@387:                      Digraph &g,
alpar@387:                      CapacityMap& capacity,
alpar@561:                      typename CapacityMap::Value infty = 0,
alpar@387:                      DimacsDescriptor desc=DimacsDescriptor()) {
alpar@386:     typename Digraph::Node u,v;
alpar@387:     if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
alpar@387:     if(desc.type!=DimacsDescriptor::MAX || desc.type!=DimacsDescriptor::SP)
alpar@387:       throw FormatError("Problem type mismatch");
alpar@561:     _readDimacs(is, g, capacity, u, v, infty, desc);
alpar@385:   }
alpar@385: 
alpar@525:   template<typename Graph>
alpar@525:   typename enable_if<lemon::UndirectedTagIndicator<Graph>,void>::type
alpar@525:   _addArcEdge(Graph &g, typename Graph::Node s, typename Graph::Node t,
alpar@525:               dummy<0> = 0)
alpar@525:   {
alpar@525:     g.addEdge(s,t);
alpar@525:   }
alpar@525:   template<typename Graph>
alpar@525:   typename disable_if<lemon::UndirectedTagIndicator<Graph>,void>::type
alpar@525:   _addArcEdge(Graph &g, typename Graph::Node s, typename Graph::Node t,
alpar@525:               dummy<1> = 1)
alpar@525:   {
alpar@525:     g.addArc(s,t);
alpar@525:   }
alpar@525:   
kpeter@584:   /// \brief DIMACS plain (di)graph reader function.
alpar@385:   ///
kpeter@584:   /// This function reads a plain (di)graph without any designated nodes
kpeter@584:   /// and maps (e.g. a matching instance) from DIMACS format, i.e. from 
kpeter@584:   /// DIMACS files having a line starting with
alpar@385:   /// \code
alpar@385:   ///   p mat
alpar@385:   /// \endcode
alpar@387:   /// At the beginning, \c g is cleared by \c g.clear().
alpar@387:   ///
alpar@387:   /// If the file type was previously evaluated by dimacsType(), then
alpar@387:   /// the descriptor struct should be given by the \c dest parameter.
alpar@525:   template<typename Graph>
alpar@525:   void readDimacsMat(std::istream& is, Graph &g,
alpar@525:                      DimacsDescriptor desc=DimacsDescriptor())
alpar@525:   {
alpar@387:     if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
alpar@387:     if(desc.type!=DimacsDescriptor::MAT)
alpar@387:       throw FormatError("Problem type mismatch");
alpar@525: 
alpar@525:     g.clear();
alpar@525:     std::vector<typename Graph::Node> nodes;
alpar@525:     char c;
alpar@525:     int i, j;
alpar@525:     std::string str;
alpar@525:     nodes.resize(desc.nodeNum + 1);
alpar@525:     for (int k = 1; k <= desc.nodeNum; ++k) {
alpar@525:       nodes[k] = g.addNode();
alpar@525:     }
alpar@525:     
alpar@525:     while (is >> c) {
alpar@525:       switch (c) {
alpar@525:       case 'c': // comment line
alpar@525:         getline(is, str);
alpar@525:         break;
alpar@525:       case 'n': // node definition line
alpar@525:         break;
alpar@561:       case 'a': // arc definition line
alpar@525:         is >> i >> j;
alpar@525:         getline(is, str);
alpar@525:         _addArcEdge(g,nodes[i], nodes[j]);
alpar@525:         break;
alpar@525:       }
alpar@525:     }
alpar@385:   }
alpar@385: 
alpar@385:   /// DIMACS plain digraph writer function.
alpar@385:   ///
alpar@385:   /// This function writes a digraph without any designated nodes and
alpar@385:   /// maps into DIMACS format, i.e. into DIMACS file having a line
alpar@385:   /// starting with
alpar@385:   /// \code
alpar@385:   ///   p mat
alpar@385:   /// \endcode
alpar@387:   /// If \c comment is not empty, then it will be printed in the first line
alpar@387:   /// prefixed by 'c'.
alpar@385:   template<typename Digraph>
alpar@387:   void writeDimacsMat(std::ostream& os, const Digraph &g,
alpar@387:                       std::string comment="") {
alpar@385:     typedef typename Digraph::NodeIt NodeIt;
alpar@385:     typedef typename Digraph::ArcIt ArcIt;
alpar@385: 
alpar@440:     if(!comment.empty())
alpar@387:       os << "c " << comment << std::endl;
alpar@385:     os << "p mat " << g.nodeNum() << " " << g.arcNum() << std::endl;
alpar@385: 
alpar@385:     typename Digraph::template NodeMap<int> nodes(g);
alpar@385:     int i = 1;
alpar@385:     for(NodeIt v(g); v != INVALID; ++v) {
alpar@385:       nodes.set(v, i);
alpar@385:       ++i;
alpar@385:     }
alpar@385:     for(ArcIt e(g); e != INVALID; ++e) {
alpar@385:       os << "a " << nodes[g.source(e)] << " " << nodes[g.target(e)]
alpar@385:          << std::endl;
alpar@385:     }
alpar@385:   }
alpar@385: 
alpar@385:   /// @}
alpar@385: 
alpar@385: } //namespace lemon
alpar@385: 
alpar@385: #endif //LEMON_DIMACS_H