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alpar (Alpar Juttner)
alpar@cs.elte.hu
Accept negative values as unbounded capacity in dimacs readers (#243) and some doc improvements.
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3 files changed with 87 insertions and 26 deletions:
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Ignore white space 6 line context
... ...
@@ -22,9 +22,9 @@
22 22
#include <iostream>
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#include <string>
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#include <vector>
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#include <limits>
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#include <lemon/maps.h>
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#include <lemon/error.h>
27

	
28 28
/// \ingroup dimacs_group
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/// \file
30 30
/// \brief DIMACS file format reader.
... ...
@@ -55,7 +55,7 @@
55 55

	
56 56
  ///Discover the type of a DIMACS file
57 57

	
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  ///It starts seeking the begining of the file for the problem type
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  ///It starts seeking the beginning of the file for the problem type
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  ///and size info. The found data is returned in a special struct
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  ///that can be evaluated and passed to the appropriate reader
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  ///function.
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@@ -105,9 +105,17 @@
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  ///   p min
106 106
  /// \endcode
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  /// At the beginning, \c g is cleared by \c g.clear(). The supply
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  /// amount of the nodes are written to \c supply (signed). The
109
  /// lower bounds, capacities and costs of the arcs are written to
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  /// \c lower, \c capacity and \c cost.
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  /// amount of the nodes are written to the \c supply node map
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  /// (they are signed values). The lower bounds, capacities and costs
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  /// of the arcs are written to the \c lower, \c capacity and \c cost
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  /// arc maps.
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  ///
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  /// If the capacity of an arc is less than the lower bound, it will
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  /// be set to "infinite" instead. The actual value of "infinite" is
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  /// contolled by the \c infty parameter. If it is 0 (the default value),
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  /// \c std::numeric_limits<Capacity>::infinity() will be used if available,
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  /// \c std::numeric_limits<Capacity>::max() otherwise. If \c infty is set to
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  /// a non-zero value, that value will be used as "infinite".
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  ///
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  /// If the file type was previously evaluated by dimacsType(), then
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  /// the descriptor struct should be given by the \c dest parameter.
... ...
@@ -120,6 +128,7 @@
120 128
                     CapacityMap& capacity,
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                     CostMap& cost,
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                     SupplyMap& supply,
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                     typename CapacityMap::Value infty = 0,
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                     DimacsDescriptor desc=DimacsDescriptor())
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  {
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    g.clear();
... ...
@@ -142,6 +151,12 @@
142 151
    typename CapacityMap::Value low;
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    typename CapacityMap::Value cap;
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    typename CostMap::Value co;
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    typedef typename CapacityMap::Value Capacity;
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    if(infty==0)
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      infty = std::numeric_limits<Capacity>::has_infinity ?
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        std::numeric_limits<Capacity>::infinity() :
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        std::numeric_limits<Capacity>::max();
159

	
145 160
    while (is >> c) {
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      switch (c) {
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      case 'c': // comment line
... ...
@@ -152,15 +167,15 @@
152 167
        getline(is, str);
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        supply.set(nodes[i], sup);
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        break;
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      case 'a': // arc (arc) definition line
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      case 'a': // arc definition line
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        is >> i >> j >> low >> cap >> co;
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        getline(is, str);
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        e = g.addArc(nodes[i], nodes[j]);
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        lower.set(e, low);
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        if (cap >= 0)
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        if (cap >= low)
161 176
          capacity.set(e, cap);
162 177
        else
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          capacity.set(e, -1);
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          capacity.set(e, infty);
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        cost.set(e, co);
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        break;
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      }
... ...
@@ -173,6 +188,7 @@
173 188
                   CapacityMap& capacity,
174 189
                   typename Digraph::Node &s,
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                   typename Digraph::Node &t,
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                   typename CapacityMap::Value infty = 0,
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                   DimacsDescriptor desc=DimacsDescriptor()) {
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    g.clear();
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    s=t=INVALID;
... ...
@@ -186,7 +202,13 @@
186 202
    for (int k = 1; k <= desc.nodeNum; ++k) {
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      nodes[k] = g.addNode();
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    }
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    typedef typename CapacityMap::Value Capacity;
189 206

	
207
    if(infty==0)
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      infty = std::numeric_limits<Capacity>::has_infinity ?
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        std::numeric_limits<Capacity>::infinity() :
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        std::numeric_limits<Capacity>::max();
211
 
190 212
    while (is >> c) {
191 213
      switch (c) {
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      case 'c': // comment line
... ...
@@ -205,14 +227,23 @@
205 227
          if (d == 't') t = nodes[i];
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        }
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        break;
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      case 'a': // arc (arc) definition line
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        if (desc.type==DimacsDescriptor::SP ||
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            desc.type==DimacsDescriptor::MAX) {
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      case 'a': // arc definition line
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        if (desc.type==DimacsDescriptor::SP) {
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          is >> i >> j >> _cap;
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          getline(is, str);
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          e = g.addArc(nodes[i], nodes[j]);
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          capacity.set(e, _cap);
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        } else {
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        } 
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        else if (desc.type==DimacsDescriptor::MAX) {
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          is >> i >> j >> _cap;
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          getline(is, str);
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          e = g.addArc(nodes[i], nodes[j]);
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          if (_cap >= 0)
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            capacity.set(e, _cap);
243
          else
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            capacity.set(e, infty);
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        }
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        else {
216 247
          is >> i >> j;
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          getline(is, str);
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          g.addArc(nodes[i], nodes[j]);
... ...
@@ -230,8 +261,15 @@
230 261
  ///   p max
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  /// \endcode
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  /// At the beginning, \c g is cleared by \c g.clear(). The arc
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  /// capacities are written to \c capacity and \c s and \c t are
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  /// set to the source and the target nodes.
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  /// capacities are written to the \c capacity arc map and \c s and
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  /// \c t are set to the source and the target nodes.
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  ///
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  /// If the capacity of an arc is negative, it will
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  /// be set to "infinite" instead. The actual value of "infinite" is
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  /// contolled by the \c infty parameter. If it is 0 (the default value),
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  /// \c std::numeric_limits<Capacity>::infinity() will be used if available,
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  /// \c std::numeric_limits<Capacity>::max() otherwise. If \c infty is set to
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  /// a non-zero value, that value will be used as "infinite".
235 273
  ///
236 274
  /// If the file type was previously evaluated by dimacsType(), then
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  /// the descriptor struct should be given by the \c dest parameter.
... ...
@@ -241,11 +279,12 @@
241 279
                     CapacityMap& capacity,
242 280
                     typename Digraph::Node &s,
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                     typename Digraph::Node &t,
282
                     typename CapacityMap::Value infty = 0,
244 283
                     DimacsDescriptor desc=DimacsDescriptor()) {
245 284
    if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
246 285
    if(desc.type!=DimacsDescriptor::MAX)
247 286
      throw FormatError("Problem type mismatch");
248
    _readDimacs(is,g,capacity,s,t,desc);
287
    _readDimacs(is,g,capacity,s,t,infty,desc);
249 288
  }
250 289

	
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  /// DIMACS shortest path reader function.
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@@ -256,7 +295,7 @@
256 295
  ///   p sp
257 296
  /// \endcode
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  /// At the beginning, \c g is cleared by \c g.clear(). The arc
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  /// lengths are written to \c length and \c s is set to the
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  /// lengths are written to the \c length arc map and \c s is set to the
260 299
  /// source node.
261 300
  ///
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  /// If the file type was previously evaluated by dimacsType(), then
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@@ -271,15 +310,24 @@
271 310
    if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
272 311
    if(desc.type!=DimacsDescriptor::SP)
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      throw FormatError("Problem type mismatch");
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    _readDimacs(is, g, length, s, t,desc);
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    _readDimacs(is, g, length, s, t, 0, desc);
275 314
  }
276 315

	
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  /// DIMACS capacitated digraph reader function.
278 317
  ///
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  /// This function reads an arc capacitated digraph instance from
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  /// DIMACS 'mat' or 'sp' format.
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  /// DIMACS 'max' or 'sp' format.
281 320
  /// At the beginning, \c g is cleared by \c g.clear()
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  /// and the arc capacities/lengths are written to \c capacity.
321
  /// and the arc capacities/lengths are written to the \c capacity
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  /// arc map.
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  ///
324
  /// In case of the 'max' format, if the capacity of an arc is negative,
325
  /// it will
326
  /// be set to "infinite" instead. The actual value of "infinite" is
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  /// contolled by the \c infty parameter. If it is 0 (the default value),
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  /// \c std::numeric_limits<Capacity>::infinity() will be used if available,
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  /// \c std::numeric_limits<Capacity>::max() otherwise. If \c infty is set to
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  /// a non-zero value, that value will be used as "infinite".
283 331
  ///
284 332
  /// If the file type was previously evaluated by dimacsType(), then
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  /// the descriptor struct should be given by the \c dest parameter.
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@@ -287,12 +335,13 @@
287 335
  void readDimacsCap(std::istream& is,
288 336
                     Digraph &g,
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                     CapacityMap& capacity,
338
                     typename CapacityMap::Value infty = 0,
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                     DimacsDescriptor desc=DimacsDescriptor()) {
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    typename Digraph::Node u,v;
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    if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
293 342
    if(desc.type!=DimacsDescriptor::MAX || desc.type!=DimacsDescriptor::SP)
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      throw FormatError("Problem type mismatch");
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    _readDimacs(is, g, capacity, u, v, desc);
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    _readDimacs(is, g, capacity, u, v, infty, desc);
296 345
  }
297 346

	
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  template<typename Graph>
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@@ -347,7 +396,7 @@
347 396
        break;
348 397
      case 'n': // node definition line
349 398
        break;
350
      case 'a': // arc (arc) definition line
399
      case 'a': // arc definition line
351 400
        is >> i >> j;
352 401
        getline(is, str);
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        _addArcEdge(g,nodes[i], nodes[j]);
Ignore white space 6 line context
... ...
@@ -72,7 +72,7 @@
72 72

	
73 73
template<class Value>
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void solve_max(ArgParser &ap, std::istream &is, std::ostream &,
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              DimacsDescriptor &desc)
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               Value infty, DimacsDescriptor &desc)
76 76
{
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  bool report = !ap.given("q");
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  Digraph g;
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@@ -80,7 +80,7 @@
80 80
  Digraph::ArcMap<Value> cap(g);
81 81
  Timer ti;
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  ti.restart();
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  readDimacsMax(is, g, cap, s, t, desc);
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  readDimacsMax(is, g, cap, s, t, infty, desc);
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  if(report) std::cerr << "Read the file: " << ti << '\n';
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  ti.restart();
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  Preflow<Digraph, Digraph::ArcMap<Value> > pre(g,cap,s,t);
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@@ -115,6 +115,17 @@
115 115
void solve(ArgParser &ap, std::istream &is, std::ostream &os,
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           DimacsDescriptor &desc)
117 117
{
118
  std::stringstream iss(ap["infcap"]);
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  Value infty;
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  iss >> infty;
121
  if(iss.fail())
122
    {
123
      std::cerr << "Cannot interpret '"
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                << static_cast<std::string>(ap["infcap"]) << "' as infinite"
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                << std::endl;
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      exit(1);
127
    }
128
  
118 129
  switch(desc.type)
119 130
    {
120 131
    case DimacsDescriptor::MIN:
... ...
@@ -122,7 +133,7 @@
122 133
        "\n\n Sorry, the min. cost flow solver is not yet available.\n";
123 134
      break;
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    case DimacsDescriptor::MAX:
125
      solve_max<Value>(ap,is,os,desc);
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      solve_max<Value>(ap,is,os,infty,desc);
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      break;
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    case DimacsDescriptor::SP:
128 139
      solve_sp<Value>(ap,is,os,desc);
... ...
@@ -159,6 +170,7 @@
159 170
    .boolOption("ldouble","Use 'long double' for capacities, costs etc.")
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    .optionGroup("datatype","ldouble")
161 172
    .onlyOneGroup("datatype")
173
    .stringOption("infcap","Value used for 'very high' capacities","0")
162 174
    .run();
163 175

	
164 176
  std::ifstream input;
Ignore white space 6 line context
... ...
@@ -96,7 +96,7 @@
96 96
        Digraph digraph;
97 97
        DoubleArcMap lower(digraph), capacity(digraph), cost(digraph);
98 98
        DoubleNodeMap supply(digraph);
99
        readDimacsMin(is, digraph, lower, capacity, cost, supply, desc);
99
        readDimacsMin(is, digraph, lower, capacity, cost, supply, 0, desc);
100 100
        DigraphWriter<Digraph>(digraph, os).
101 101
          nodeMap("supply", supply).
102 102
          arcMap("lower", lower).
... ...
@@ -111,7 +111,7 @@
111 111
        Digraph digraph;
112 112
        Node s, t;
113 113
        DoubleArcMap capacity(digraph);
114
        readDimacsMax(is, digraph, capacity, s, t, desc);
114
        readDimacsMax(is, digraph, capacity, s, t, 0, desc);
115 115
        DigraphWriter<Digraph>(digraph, os).
116 116
          arcMap("capacity", capacity).
117 117
          node("source", s).
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