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kpeter (Peter Kovacs)
kpeter@inf.elte.hu
Support LEQ and GEQ supply constraints in dimacs-solver (#234, #219)
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1 file changed with 24 insertions and 6 deletions:
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Ignore white space 6 line context
... ...
@@ -93,24 +93,42 @@
93 93

	
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template<class Value>
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void solve_min(ArgParser &ap, std::istream &is, std::ostream &,
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               DimacsDescriptor &desc)
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               Value infty, DimacsDescriptor &desc)
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{
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  bool report = !ap.given("q");
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  Digraph g;
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  Digraph::ArcMap<Value> lower(g), cap(g), cost(g);
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  Digraph::NodeMap<Value> sup(g);
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  Timer ti;
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  ti.restart();
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  readDimacsMin(is, g, lower, cap, cost, sup, 0, desc);
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  readDimacsMin(is, g, lower, cap, cost, sup, infty, desc);
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  ti.stop();
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  Value sum_sup = 0;
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  for (Digraph::NodeIt n(g); n != INVALID; ++n) {
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    sum_sup += sup[n];
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  }
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  if (report) {
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    std::cerr << "Sum of supply values: " << sum_sup << "\n";
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    if (sum_sup <= 0)
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      std::cerr << "GEQ supply contraints are used for NetworkSimplex\n\n";
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    else
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      std::cerr << "LEQ supply contraints are used for NetworkSimplex\n\n";
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  }
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  if (report) std::cerr << "Read the file: " << ti << '\n';
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  ti.restart();
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  NetworkSimplex<Digraph, Value> ns(g);
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  ns.lowerMap(lower).capacityMap(cap).costMap(cost).supplyMap(sup);
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  if (sum_sup > 0) ns.problemType(ns.LEQ);
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  if (report) std::cerr << "Setup NetworkSimplex class: " << ti << '\n';
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  ti.restart();
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  ns.run();
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  if (report) std::cerr << "Run NetworkSimplex: " << ti << '\n';
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  if (report) std::cerr << "\nMin flow cost: " << ns.totalCost() << '\n';
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  bool res = ns.run();
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  if (report) {
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    std::cerr << "Run NetworkSimplex: " << ti << "\n\n";
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    std::cerr << "Feasible flow: " << (res ? "found" : "not found") << '\n';
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    if (res) std::cerr << "Min flow cost: " << ns.totalCost() << '\n';
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  }
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}
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void solve_mat(ArgParser &ap, std::istream &is, std::ostream &,
... ...
@@ -151,7 +169,7 @@
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  switch(desc.type)
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    {
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    case DimacsDescriptor::MIN:
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      solve_min<Value>(ap,is,os,desc);
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      solve_min<Value>(ap,is,os,infty,desc);
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      break;
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    case DimacsDescriptor::MAX:
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      solve_max<Value>(ap,is,os,infty,desc);
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