Location: LEMON/LEMON-official/tools/dimacs-solver.cc

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kpeter (Peter Kovacs)
Entirely rework CapacityScaling (#180) - Use the new interface similarly to NetworkSimplex. - Rework the implementation using an efficient internal structure for handling the residual network. This improvement made the code much faster (up to 2-5 times faster on large graphs). - Handle GEQ supply type (LEQ is not supported). - Handle negative costs for arcs of finite capacity. (Note that this algorithm cannot handle arcs of negative cost and infinite upper bound, thus it returns UNBOUNDED if such an arc exists.) - Extend the documentation.
/* -*- mode: C++; indent-tabs-mode: nil; -*-
*
* This file is a part of LEMON, a generic C++ optimization library.
*
* Copyright (C) 2003-2009
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
* (Egervary Research Group on Combinatorial Optimization, EGRES).
*
* Permission to use, modify and distribute this software is granted
* provided that this copyright notice appears in all copies. For
* precise terms see the accompanying LICENSE file.
*
* This software is provided "AS IS" with no warranty of any kind,
* express or implied, and with no claim as to its suitability for any
* purpose.
*
*/
///\ingroup tools
///\file
///\brief DIMACS problem solver.
///
/// This program solves various problems given in DIMACS format.
///
/// See
/// \code
/// dimacs-solver --help
/// \endcode
/// for more info on usage.
#include <iostream>
#include <fstream>
#include <cstring>
#include <lemon/smart_graph.h>
#include <lemon/dimacs.h>
#include <lemon/lgf_writer.h>
#include <lemon/time_measure.h>
#include <lemon/arg_parser.h>
#include <lemon/error.h>
#include <lemon/dijkstra.h>
#include <lemon/preflow.h>
#include <lemon/matching.h>
#include <lemon/network_simplex.h>
using namespace lemon;
typedef SmartDigraph Digraph;
DIGRAPH_TYPEDEFS(Digraph);
typedef SmartGraph Graph;
template<class Value>
void solve_sp(ArgParser &ap, std::istream &is, std::ostream &,
DimacsDescriptor &desc)
{
bool report = !ap.given("q");
Digraph g;
Node s;
Digraph::ArcMap<Value> len(g);
Timer t;
t.restart();
readDimacsSp(is, g, len, s, desc);
if(report) std::cerr << "Read the file: " << t << '\n';
t.restart();
Dijkstra<Digraph, Digraph::ArcMap<Value> > dij(g,len);
if(report) std::cerr << "Setup Dijkstra class: " << t << '\n';
t.restart();
dij.run(s);
if(report) std::cerr << "Run Dijkstra: " << t << '\n';
}
template<class Value>
void solve_max(ArgParser &ap, std::istream &is, std::ostream &,
Value infty, DimacsDescriptor &desc)
{
bool report = !ap.given("q");
Digraph g;
Node s,t;
Digraph::ArcMap<Value> cap(g);
Timer ti;
ti.restart();
readDimacsMax(is, g, cap, s, t, infty, desc);
if(report) std::cerr << "Read the file: " << ti << '\n';
ti.restart();
Preflow<Digraph, Digraph::ArcMap<Value> > pre(g,cap,s,t);
if(report) std::cerr << "Setup Preflow class: " << ti << '\n';
ti.restart();
pre.run();
if(report) std::cerr << "Run Preflow: " << ti << '\n';
if(report) std::cerr << "\nMax flow value: " << pre.flowValue() << '\n';
}
template<class Value>
void solve_min(ArgParser &ap, std::istream &is, std::ostream &,
Value infty, DimacsDescriptor &desc)
{
bool report = !ap.given("q");
Digraph g;
Digraph::ArcMap<Value> lower(g), cap(g), cost(g);
Digraph::NodeMap<Value> sup(g);
Timer ti;
ti.restart();
readDimacsMin(is, g, lower, cap, cost, sup, infty, desc);
ti.stop();
Value sum_sup = 0;
for (Digraph::NodeIt n(g); n != INVALID; ++n) {
sum_sup += sup[n];
}
if (report) {
std::cerr << "Sum of supply values: " << sum_sup << "\n";
if (sum_sup <= 0)
std::cerr << "GEQ supply contraints are used for NetworkSimplex\n\n";
else
std::cerr << "LEQ supply contraints are used for NetworkSimplex\n\n";
}
if (report) std::cerr << "Read the file: " << ti << '\n';
ti.restart();
NetworkSimplex<Digraph, Value> ns(g);
ns.lowerMap(lower).upperMap(cap).costMap(cost).supplyMap(sup);
if (sum_sup > 0) ns.supplyType(ns.LEQ);
if (report) std::cerr << "Setup NetworkSimplex class: " << ti << '\n';
ti.restart();
bool res = ns.run();
if (report) {
std::cerr << "Run NetworkSimplex: " << ti << "\n\n";
std::cerr << "Feasible flow: " << (res ? "found" : "not found") << '\n';
if (res) std::cerr << "Min flow cost: " << ns.totalCost() << '\n';
}
}
void solve_mat(ArgParser &ap, std::istream &is, std::ostream &,
DimacsDescriptor &desc)
{
bool report = !ap.given("q");
Graph g;
Timer ti;
ti.restart();
readDimacsMat(is, g, desc);
if(report) std::cerr << "Read the file: " << ti << '\n';
ti.restart();
MaxMatching<Graph> mat(g);
if(report) std::cerr << "Setup MaxMatching class: " << ti << '\n';
ti.restart();
mat.run();
if(report) std::cerr << "Run MaxMatching: " << ti << '\n';
if(report) std::cerr << "\nCardinality of max matching: "
<< mat.matchingSize() << '\n';
}
template<class Value>
void solve(ArgParser &ap, std::istream &is, std::ostream &os,
DimacsDescriptor &desc)
{
std::stringstream iss(static_cast<std::string>(ap["infcap"]));
Value infty;
iss >> infty;
if(iss.fail())
{
std::cerr << "Cannot interpret '"
<< static_cast<std::string>(ap["infcap"]) << "' as infinite"
<< std::endl;
exit(1);
}
switch(desc.type)
{
case DimacsDescriptor::MIN:
solve_min<Value>(ap,is,os,infty,desc);
break;
case DimacsDescriptor::MAX:
solve_max<Value>(ap,is,os,infty,desc);
break;
case DimacsDescriptor::SP:
solve_sp<Value>(ap,is,os,desc);
break;
case DimacsDescriptor::MAT:
solve_mat(ap,is,os,desc);
break;
default:
break;
}
}
int main(int argc, const char *argv[]) {
typedef SmartDigraph Digraph;
typedef Digraph::Arc Arc;
std::string inputName;
std::string outputName;
ArgParser ap(argc, argv);
ap.other("[INFILE [OUTFILE]]",
"If either the INFILE or OUTFILE file is missing the standard\n"
" input/output will be used instead.")
.boolOption("q", "Do not print any report")
.boolOption("int","Use 'int' for capacities, costs etc. (default)")
.optionGroup("datatype","int")
#ifdef LEMON_HAVE_LONG_LONG
.boolOption("long","Use 'long long' for capacities, costs etc.")
.optionGroup("datatype","long")
#endif
.boolOption("double","Use 'double' for capacities, costs etc.")
.optionGroup("datatype","double")
.boolOption("ldouble","Use 'long double' for capacities, costs etc.")
.optionGroup("datatype","ldouble")
.onlyOneGroup("datatype")
.stringOption("infcap","Value used for 'very high' capacities","0")
.run();
std::ifstream input;
std::ofstream output;
switch(ap.files().size())
{
case 2:
output.open(ap.files()[1].c_str());
if (!output) {
throw IoError("Cannot open the file for writing", ap.files()[1]);
}
case 1:
input.open(ap.files()[0].c_str());
if (!input) {
throw IoError("File cannot be found", ap.files()[0]);
}
case 0:
break;
default:
std::cerr << ap.commandName() << ": too many arguments\n";
return 1;
}
std::istream& is = (ap.files().size()<1 ? std::cin : input);
std::ostream& os = (ap.files().size()<2 ? std::cout : output);
DimacsDescriptor desc = dimacsType(is);
if(!ap.given("q"))
{
std::cout << "Problem type: ";
switch(desc.type)
{
case DimacsDescriptor::MIN:
std::cout << "min";
break;
case DimacsDescriptor::MAX:
std::cout << "max";
break;
case DimacsDescriptor::SP:
std::cout << "sp";
case DimacsDescriptor::MAT:
std::cout << "mat";
break;
default:
exit(1);
break;
}
std::cout << "\nNum of nodes: " << desc.nodeNum;
std::cout << "\nNum of arcs: " << desc.edgeNum;
std::cout << "\n\n";
}
if(ap.given("double"))
solve<double>(ap,is,os,desc);
else if(ap.given("ldouble"))
solve<long double>(ap,is,os,desc);
#ifdef LEMON_HAVE_LONG_LONG
else if(ap.given("long"))
solve<long long>(ap,is,os,desc);
#endif
else solve<int>(ap,is,os,desc);
return 0;
}