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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 4 line context
... ...
@@ -23,7 +23,7 @@
23 23
#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
... ...
@@ -56,5 +56,5 @@
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  ///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
... ...
@@ -106,7 +106,15 @@
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
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  /// 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
... ...
@@ -121,4 +129,5 @@
121 129
                     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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  {
... ...
@@ -143,4 +152,10 @@
143 152
    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) {
... ...
@@ -153,13 +168,13 @@
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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)
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          capacity.set(e, cap);
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        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;
... ...
@@ -174,4 +189,5 @@
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()) {
177 193
    g.clear();
... ...
@@ -187,5 +203,11 @@
187 203
      nodes[k] = g.addNode();
188 204
    }
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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();
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190 212
    while (is >> c) {
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      switch (c) {
... ...
@@ -206,12 +228,21 @@
206 228
        }
207 229
        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);
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          else
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            capacity.set(e, infty);
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        }
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        else {
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          is >> i >> j;
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          getline(is, str);
... ...
@@ -231,6 +262,13 @@
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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".
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  ///
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  /// If the file type was previously evaluated by dimacsType(), then
... ...
@@ -242,9 +280,10 @@
242 280
                     typename Digraph::Node &s,
243 281
                     typename Digraph::Node &t,
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                     typename CapacityMap::Value infty = 0,
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                     DimacsDescriptor desc=DimacsDescriptor()) {
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    if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
246 285
    if(desc.type!=DimacsDescriptor::MAX)
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      throw FormatError("Problem type mismatch");
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    _readDimacs(is,g,capacity,s,t,desc);
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    _readDimacs(is,g,capacity,s,t,infty,desc);
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  }
250 289

	
... ...
@@ -257,5 +296,5 @@
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.
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  ///
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@@ -272,5 +311,5 @@
272 311
    if(desc.type!=DimacsDescriptor::SP)
273 312
      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

	
... ...
@@ -278,7 +317,16 @@
278 317
  ///
279 318
  /// 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.
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  /// 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.
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  /// and the arc capacities/lengths are written to the \c capacity
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  /// arc map.
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  ///
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  /// In case of the 'max' format, if the capacity of an arc is negative,
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  /// 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".
283 331
  ///
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  /// If the file type was previously evaluated by dimacsType(), then
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@@ -288,4 +336,5 @@
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;
... ...
@@ -293,5 +342,5 @@
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);
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  }
297 346

	
... ...
@@ -348,5 +397,5 @@
348 397
      case 'n': // node definition line
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        break;
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      case 'a': // arc (arc) definition line
399
      case 'a': // arc definition line
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        is >> i >> j;
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        getline(is, str);
Ignore white space 4 line context
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@@ -73,5 +73,5 @@
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)
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{
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  bool report = !ap.given("q");
... ...
@@ -81,5 +81,5 @@
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  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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@@ -116,4 +116,15 @@
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           DimacsDescriptor &desc)
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{
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  std::stringstream iss(ap["infcap"]);
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  Value infty;
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  iss >> infty;
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  if(iss.fail())
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    {
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      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);
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    }
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  switch(desc.type)
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    {
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@@ -123,5 +134,5 @@
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:
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@@ -160,4 +171,5 @@
160 171
    .optionGroup("datatype","ldouble")
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    .onlyOneGroup("datatype")
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    .stringOption("infcap","Value used for 'very high' capacities","0")
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    .run();
163 175

	
Ignore white space 4 line context
... ...
@@ -97,5 +97,5 @@
97 97
        DoubleArcMap lower(digraph), capacity(digraph), cost(digraph);
98 98
        DoubleNodeMap supply(digraph);
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        readDimacsMin(is, digraph, lower, capacity, cost, supply, desc);
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        readDimacsMin(is, digraph, lower, capacity, cost, supply, 0, desc);
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        DigraphWriter<Digraph>(digraph, os).
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          nodeMap("supply", supply).
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@@ -112,5 +112,5 @@
112 112
        Node s, t;
113 113
        DoubleArcMap capacity(digraph);
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        readDimacsMax(is, digraph, capacity, s, t, desc);
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        readDimacsMax(is, digraph, capacity, s, t, 0, desc);
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        DigraphWriter<Digraph>(digraph, os).
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          arcMap("capacity", capacity).
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