alpar@400: /* -*- mode: C++; indent-tabs-mode: nil; -*-
alpar@400:  *
alpar@400:  * This file is a part of LEMON, a generic C++ optimization library.
alpar@400:  *
alpar@463:  * Copyright (C) 2003-2009
alpar@400:  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
alpar@400:  * (Egervary Research Group on Combinatorial Optimization, EGRES).
alpar@400:  *
alpar@400:  * Permission to use, modify and distribute this software is granted
alpar@400:  * provided that this copyright notice appears in all copies. For
alpar@400:  * precise terms see the accompanying LICENSE file.
alpar@400:  *
alpar@400:  * This software is provided "AS IS" with no warranty of any kind,
alpar@400:  * express or implied, and with no claim as to its suitability for any
alpar@400:  * purpose.
alpar@400:  *
alpar@400:  */
alpar@400: 
alpar@400: #ifndef LEMON_DIMACS_H
alpar@400: #define LEMON_DIMACS_H
alpar@400: 
alpar@400: #include <iostream>
alpar@400: #include <string>
alpar@400: #include <vector>
alpar@400: #include <lemon/maps.h>
alpar@402: #include <lemon/error.h>
alpar@400: 
alpar@400: /// \ingroup dimacs_group
alpar@400: /// \file
alpar@400: /// \brief DIMACS file format reader.
alpar@400: 
alpar@400: namespace lemon {
alpar@400: 
alpar@400:   /// \addtogroup dimacs_group
alpar@400:   /// @{
alpar@400: 
alpar@402:   /// DIMACS file type descriptor.
alpar@402:   struct DimacsDescriptor
alpar@402:   {
alpar@402:     ///File type enum
alpar@402:     enum Type
alpar@402:       {
alpar@402:         NONE, MIN, MAX, SP, MAT
alpar@402:       };
alpar@402:     ///The file type
alpar@402:     Type type;
kpeter@403:     ///The number of nodes in the graph
alpar@402:     int nodeNum;
kpeter@403:     ///The number of edges in the graph
alpar@402:     int edgeNum;
alpar@402:     int lineShift;
alpar@402:     /// Constructor. Sets the type to NONE.
alpar@402:     DimacsDescriptor() : type(NONE) {}
alpar@402:   };
alpar@402: 
alpar@402:   ///Discover the type of a DIMACS file
alpar@402: 
alpar@402:   ///It starts seeking the begining of the file for the problem type
kpeter@403:   ///and size info. The found data is returned in a special struct
alpar@402:   ///that can be evaluated and passed to the appropriate reader
alpar@402:   ///function.
alpar@402:   DimacsDescriptor dimacsType(std::istream& is)
alpar@402:   {
alpar@402:     DimacsDescriptor r;
alpar@402:     std::string problem,str;
alpar@402:     char c;
alpar@402:     r.lineShift=0;
alpar@402:     while (is >> c)
alpar@402:       switch(c)
alpar@402:         {
alpar@402:         case 'p':
alpar@402:           if(is >> problem >> r.nodeNum >> r.edgeNum)
alpar@402:             {
alpar@402:               getline(is, str);
alpar@402:               r.lineShift++;
alpar@402:               if(problem=="min") r.type=DimacsDescriptor::MIN;
alpar@402:               else if(problem=="max") r.type=DimacsDescriptor::MAX;
alpar@402:               else if(problem=="sp") r.type=DimacsDescriptor::SP;
alpar@402:               else if(problem=="mat") r.type=DimacsDescriptor::MAT;
alpar@402:               else throw FormatError("Unknown problem type");
alpar@402:               return r;
alpar@402:             }
alpar@402:           else
alpar@402:             {
alpar@402:               throw FormatError("Missing or wrong problem type declaration.");
alpar@402:             }
alpar@402:           break;
alpar@402:         case 'c':
alpar@402:           getline(is, str);
alpar@402:           r.lineShift++;
alpar@402:           break;
alpar@402:         default:
alpar@402:           throw FormatError("Unknown DIMACS declaration.");
alpar@402:         }
alpar@402:     throw FormatError("Missing problem type declaration.");
alpar@402:   }
alpar@402: 
alpar@402: 
alpar@402: 
kpeter@403:   /// DIMACS minimum cost flow reader function.
alpar@400:   ///
kpeter@403:   /// This function reads a minimum cost flow instance from DIMACS format,
kpeter@403:   /// i.e. from a DIMACS file having a line starting with
alpar@400:   /// \code
alpar@400:   ///   p min
alpar@400:   /// \endcode
alpar@402:   /// At the beginning, \c g is cleared by \c g.clear(). The supply
alpar@400:   /// amount of the nodes are written to \c supply (signed). The
alpar@400:   /// lower bounds, capacities and costs of the arcs are written to
alpar@400:   /// \c lower, \c capacity and \c cost.
alpar@402:   ///
alpar@402:   /// If the file type was previously evaluated by dimacsType(), then
alpar@402:   /// the descriptor struct should be given by the \c dest parameter.
alpar@400:   template <typename Digraph, typename LowerMap,
alpar@402:             typename CapacityMap, typename CostMap,
alpar@402:             typename SupplyMap>
alpar@402:   void readDimacsMin(std::istream& is,
alpar@402:                      Digraph &g,
alpar@402:                      LowerMap& lower,
alpar@402:                      CapacityMap& capacity,
alpar@402:                      CostMap& cost,
alpar@402:                      SupplyMap& supply,
alpar@402:                      DimacsDescriptor desc=DimacsDescriptor())
alpar@400:   {
alpar@400:     g.clear();
alpar@400:     std::vector<typename Digraph::Node> nodes;
alpar@400:     typename Digraph::Arc e;
alpar@400:     std::string problem, str;
alpar@400:     char c;
alpar@400:     int i, j;
alpar@402:     if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
alpar@402:     if(desc.type!=DimacsDescriptor::MIN)
alpar@402:       throw FormatError("Problem type mismatch");
alpar@402: 
alpar@402:     nodes.resize(desc.nodeNum + 1);
alpar@402:     for (int k = 1; k <= desc.nodeNum; ++k) {
alpar@402:       nodes[k] = g.addNode();
alpar@402:       supply.set(nodes[k], 0);
alpar@402:     }
alpar@402: 
alpar@400:     typename SupplyMap::Value sup;
alpar@400:     typename CapacityMap::Value low;
alpar@400:     typename CapacityMap::Value cap;
alpar@400:     typename CostMap::Value co;
alpar@400:     while (is >> c) {
alpar@400:       switch (c) {
alpar@400:       case 'c': // comment line
alpar@400:         getline(is, str);
alpar@400:         break;
alpar@400:       case 'n': // node definition line
alpar@400:         is >> i >> sup;
alpar@400:         getline(is, str);
alpar@400:         supply.set(nodes[i], sup);
alpar@400:         break;
alpar@400:       case 'a': // arc (arc) definition line
alpar@400:         is >> i >> j >> low >> cap >> co;
alpar@400:         getline(is, str);
alpar@400:         e = g.addArc(nodes[i], nodes[j]);
alpar@400:         lower.set(e, low);
alpar@400:         if (cap >= 0)
alpar@400:           capacity.set(e, cap);
alpar@400:         else
alpar@400:           capacity.set(e, -1);
alpar@400:         cost.set(e, co);
alpar@400:         break;
alpar@400:       }
alpar@400:     }
alpar@400:   }
alpar@400: 
alpar@400:   template<typename Digraph, typename CapacityMap>
alpar@402:   void _readDimacs(std::istream& is,
alpar@402:                    Digraph &g,
alpar@402:                    CapacityMap& capacity,
alpar@402:                    typename Digraph::Node &s,
alpar@402:                    typename Digraph::Node &t,
alpar@402:                    DimacsDescriptor desc=DimacsDescriptor()) {
alpar@400:     g.clear();
alpar@402:     s=t=INVALID;
alpar@400:     std::vector<typename Digraph::Node> nodes;
alpar@400:     typename Digraph::Arc e;
alpar@400:     char c, d;
alpar@400:     int i, j;
alpar@400:     typename CapacityMap::Value _cap;
alpar@400:     std::string str;
alpar@402:     nodes.resize(desc.nodeNum + 1);
alpar@402:     for (int k = 1; k <= desc.nodeNum; ++k) {
alpar@402:       nodes[k] = g.addNode();
alpar@402:     }
alpar@402: 
alpar@400:     while (is >> c) {
alpar@400:       switch (c) {
alpar@400:       case 'c': // comment line
alpar@400:         getline(is, str);
alpar@400:         break;
alpar@400:       case 'n': // node definition line
alpar@402:         if (desc.type==DimacsDescriptor::SP) { // shortest path problem
alpar@400:           is >> i;
alpar@400:           getline(is, str);
alpar@400:           s = nodes[i];
alpar@400:         }
alpar@402:         if (desc.type==DimacsDescriptor::MAX) { // max flow problem
alpar@400:           is >> i >> d;
alpar@400:           getline(is, str);
alpar@400:           if (d == 's') s = nodes[i];
alpar@400:           if (d == 't') t = nodes[i];
alpar@400:         }
alpar@400:         break;
alpar@400:       case 'a': // arc (arc) definition line
alpar@402:         if (desc.type==DimacsDescriptor::SP ||
alpar@402:             desc.type==DimacsDescriptor::MAX) {
alpar@400:           is >> i >> j >> _cap;
alpar@400:           getline(is, str);
alpar@400:           e = g.addArc(nodes[i], nodes[j]);
alpar@400:           capacity.set(e, _cap);
alpar@400:         } else {
alpar@400:           is >> i >> j;
alpar@400:           getline(is, str);
alpar@400:           g.addArc(nodes[i], nodes[j]);
alpar@400:         }
alpar@400:         break;
alpar@400:       }
alpar@400:     }
alpar@400:   }
alpar@400: 
kpeter@403:   /// DIMACS maximum flow reader function.
alpar@402:   ///
kpeter@403:   /// This function reads a maximum flow instance from DIMACS format,
kpeter@403:   /// i.e. from a DIMACS file having a line starting with
alpar@402:   /// \code
alpar@402:   ///   p max
alpar@402:   /// \endcode
alpar@402:   /// At the beginning, \c g is cleared by \c g.clear(). The arc
alpar@402:   /// capacities are written to \c capacity and \c s and \c t are
alpar@402:   /// set to the source and the target nodes.
alpar@402:   ///
alpar@402:   /// If the file type was previously evaluated by dimacsType(), then
alpar@402:   /// the descriptor struct should be given by the \c dest parameter.
alpar@402:   template<typename Digraph, typename CapacityMap>
alpar@402:   void readDimacsMax(std::istream& is,
alpar@402:                      Digraph &g,
alpar@402:                      CapacityMap& capacity,
alpar@402:                      typename Digraph::Node &s,
alpar@402:                      typename Digraph::Node &t,
alpar@402:                      DimacsDescriptor desc=DimacsDescriptor()) {
alpar@402:     if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
alpar@402:     if(desc.type!=DimacsDescriptor::MAX)
alpar@402:       throw FormatError("Problem type mismatch");
alpar@402:     _readDimacs(is,g,capacity,s,t,desc);
alpar@402:   }
alpar@402: 
alpar@400:   /// DIMACS shortest path reader function.
alpar@400:   ///
alpar@400:   /// This function reads a shortest path instance from DIMACS format,
kpeter@403:   /// i.e. from a DIMACS file having a line starting with
alpar@400:   /// \code
alpar@400:   ///   p sp
alpar@400:   /// \endcode
alpar@402:   /// At the beginning, \c g is cleared by \c g.clear(). The arc
kpeter@403:   /// lengths are written to \c length and \c s is set to the
alpar@400:   /// source node.
alpar@402:   ///
alpar@402:   /// If the file type was previously evaluated by dimacsType(), then
alpar@402:   /// the descriptor struct should be given by the \c dest parameter.
alpar@402:   template<typename Digraph, typename LengthMap>
alpar@402:   void readDimacsSp(std::istream& is,
alpar@402:                     Digraph &g,
alpar@402:                     LengthMap& length,
alpar@402:                     typename Digraph::Node &s,
alpar@402:                     DimacsDescriptor desc=DimacsDescriptor()) {
alpar@401:     typename Digraph::Node t;
alpar@402:     if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
alpar@402:     if(desc.type!=DimacsDescriptor::SP)
alpar@402:       throw FormatError("Problem type mismatch");
alpar@402:     _readDimacs(is, g, length, s, t,desc);
alpar@400:   }
alpar@400: 
alpar@400:   /// DIMACS capacitated digraph reader function.
alpar@400:   ///
alpar@400:   /// This function reads an arc capacitated digraph instance from
alpar@402:   /// DIMACS 'mat' or 'sp' format.
alpar@402:   /// At the beginning, \c g is cleared by \c g.clear()
alpar@402:   /// and the arc capacities/lengths are written to \c capacity.
alpar@402:   ///
alpar@402:   /// If the file type was previously evaluated by dimacsType(), then
alpar@402:   /// the descriptor struct should be given by the \c dest parameter.
alpar@400:   template<typename Digraph, typename CapacityMap>
alpar@402:   void readDimacsCap(std::istream& is,
alpar@402:                      Digraph &g,
alpar@402:                      CapacityMap& capacity,
alpar@402:                      DimacsDescriptor desc=DimacsDescriptor()) {
alpar@401:     typename Digraph::Node u,v;
alpar@402:     if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
alpar@402:     if(desc.type!=DimacsDescriptor::MAX || desc.type!=DimacsDescriptor::SP)
alpar@402:       throw FormatError("Problem type mismatch");
alpar@402:     _readDimacs(is, g, capacity, u, v, desc);
alpar@400:   }
alpar@400: 
alpar@400:   /// DIMACS plain digraph reader function.
alpar@400:   ///
alpar@400:   /// This function reads a digraph without any designated nodes and
alpar@400:   /// maps from DIMACS format, i.e. from DIMACS files having a line
alpar@400:   /// starting with
alpar@400:   /// \code
alpar@400:   ///   p mat
alpar@400:   /// \endcode
alpar@402:   /// At the beginning, \c g is cleared by \c g.clear().
alpar@402:   ///
alpar@402:   /// If the file type was previously evaluated by dimacsType(), then
alpar@402:   /// the descriptor struct should be given by the \c dest parameter.
alpar@400:   template<typename Digraph>
alpar@402:   void readDimacsMat(std::istream& is, Digraph &g,
alpar@402:                      DimacsDescriptor desc=DimacsDescriptor()) {
alpar@401:     typename Digraph::Node u,v;
alpar@400:     NullMap<typename Digraph::Arc, int> n;
alpar@402:     if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
alpar@402:     if(desc.type!=DimacsDescriptor::MAT)
alpar@402:       throw FormatError("Problem type mismatch");
alpar@402:     _readDimacs(is, g, n, u, v, desc);
alpar@400:   }
alpar@400: 
alpar@400:   /// DIMACS plain digraph writer function.
alpar@400:   ///
alpar@400:   /// This function writes a digraph without any designated nodes and
alpar@400:   /// maps into DIMACS format, i.e. into DIMACS file having a line
alpar@400:   /// starting with
alpar@400:   /// \code
alpar@400:   ///   p mat
alpar@400:   /// \endcode
alpar@402:   /// If \c comment is not empty, then it will be printed in the first line
alpar@402:   /// prefixed by 'c'.
alpar@400:   template<typename Digraph>
alpar@402:   void writeDimacsMat(std::ostream& os, const Digraph &g,
alpar@402:                       std::string comment="") {
alpar@400:     typedef typename Digraph::NodeIt NodeIt;
alpar@400:     typedef typename Digraph::ArcIt ArcIt;
alpar@400: 
alpar@463:     if(!comment.empty())
alpar@402:       os << "c " << comment << std::endl;
alpar@400:     os << "p mat " << g.nodeNum() << " " << g.arcNum() << std::endl;
alpar@400: 
alpar@400:     typename Digraph::template NodeMap<int> nodes(g);
alpar@400:     int i = 1;
alpar@400:     for(NodeIt v(g); v != INVALID; ++v) {
alpar@400:       nodes.set(v, i);
alpar@400:       ++i;
alpar@400:     }
alpar@400:     for(ArcIt e(g); e != INVALID; ++e) {
alpar@400:       os << "a " << nodes[g.source(e)] << " " << nodes[g.target(e)]
alpar@400:          << std::endl;
alpar@400:     }
alpar@400:   }
alpar@400: 
alpar@400:   /// @}
alpar@400: 
alpar@400: } //namespace lemon
alpar@400: 
alpar@400: #endif //LEMON_DIMACS_H