diff -r d8475431bbbb -r 8e85e6bbefdf lemon/dimacs.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lemon/dimacs.h	Mon May 23 04:48:14 2005 +0000
@@ -0,0 +1,228 @@
+/* -*- C++ -*-
+ * lemon/dimacs.h - Part of LEMON, a generic C++ optimization library
+ *
+ * Copyright (C) 2005 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.
+ *
+ */
+
+#ifndef LEMON_DIMACS_H
+#define LEMON_DIMACS_H
+
+#include <iostream>
+#include <string>
+#include <vector>
+#include <lemon/maps.h>
+#include <lemon/invalid.h>
+
+/// \ingroup dimacs_group
+/// \file
+/// \brief Dimacs file format reader.
+
+namespace lemon {
+
+  ///
+  ///@defgroup dimacs_group DIMACS format
+  ///\brief Read and write files in DIMACS format
+  ///
+  ///Tools to read a graph from or write it to a file in DIMACS format
+  ///data
+  ///\ingroup io_group
+
+  /// \addtogroup dimacs_group
+  /// @{
+
+  /// Dimacs min cost flow reader function.
+
+  /// This function reads a min cost flow instance from dimacs format,
+  /// i.e. from dimacs files having a line starting with
+  /// \code
+  /// p "min"
+  /// \endcode
+  /// At the beginning \c g is cleared by \c g.clear(). The edge
+  /// capacities are written to \c capacity, \c s and \c t are set to
+  /// the source and the target nodes resp. and the cost of the edges
+  /// are written to \c cost.
+  ///
+  /// \author Marton Makai
+  template<typename Graph, typename CapacityMap, typename CostMap>
+  void readDimacs(std::istream& is, Graph &g, CapacityMap& capacity, 
+		  typename Graph::Node &s, typename Graph::Node &t, 
+		  CostMap& cost) {
+    g.clear();
+    typename CapacityMap::Value _cap;
+    typename CostMap::Value _cost;
+    char d;
+    std::string problem;
+    char c;
+    int i, j;
+    std::string str;
+    int n, m; 
+    typename Graph::Edge e;
+    std::vector<typename Graph::Node> nodes;
+    while (is>>c) {
+      switch (c) {
+      case 'c': //comment
+	getline(is, str);
+	break;
+      case 'p': //problem definition
+	is >> problem >> n >> m;
+	getline(is, str);
+	nodes.resize(n+1);
+	for (int k=1; k<=n; ++k) nodes[k]=g.addNode();
+	break;
+      case 'n': //node definition
+	if (problem=="sp") { //shortest path problem
+	  is >> i;
+	  getline(is, str);
+	  s=nodes[i];
+	}
+	if (problem=="max" || problem=="min") { //((max) or (min cost)) flow problem
+	  is >> i >> d;
+	  getline(is, str);
+	  if (d=='s') s=nodes[i];
+	  if (d=='t') t=nodes[i];
+	}
+	break;
+      case 'a':
+	if ( problem == "max" || problem == "sp") {
+	  is >> i >> j >> _cap;
+	  getline(is, str);
+	  e=g.addEdge(nodes[i], nodes[j]);
+	  //capacity.update();
+	  capacity.set(e, _cap);
+	} else {
+	  if ( problem == "min" ) {
+	    is >> i >> j >> _cap >> _cost;
+	    getline(is, str);
+	    e=g.addEdge(nodes[i], nodes[j]);
+	    //capacity.update();
+	    capacity.set(e, _cap);
+	    //cost.update();
+	    cost.set(e, _cost);
+	  } else {
+	    is >> i >> j;
+	    getline(is, str);
+	    g.addEdge(nodes[i], nodes[j]);
+	  }
+	}
+	break;
+      }
+    }
+  }
+
+
+  /// Dimacs max flow reader function.
+
+  /// This function reads a max flow instance from dimacs format,
+  /// i.e. from dimacs files having a line starting with
+  /// \code
+  /// p "max"
+  /// \endcode
+  ///At the beginning \c g is cleared by \c g.clear(). The
+  /// edge capacities are written to \c capacity and \c s and \c t are
+  /// set to the source and the target nodes.
+  ///
+  /// \author Marton Makai
+  template<typename Graph, typename CapacityMap>
+  void readDimacs(std::istream& is, Graph &g, CapacityMap& capacity, 
+		  typename Graph::Node &s, typename Graph::Node &t) {
+    NullMap<typename Graph::Edge, int> n;
+    readDimacs(is, g, capacity, s, t, n);
+  }
+
+
+  /// Dimacs shortest path reader function.
+
+  /// This function reads a shortest path instance from dimacs format,
+  /// i.e. from dimacs files having a line starting with
+  /// \code
+  /// p "sp"
+  /// \endcode
+  /// At the beginning \c g is cleared by \c g.clear(). The edge
+  /// capacities are written to \c capacity and \c s is set to the
+  /// source node.
+  ///
+  /// \author Marton Makai
+  template<typename Graph, typename CapacityMap>
+  void readDimacs(std::istream& is, Graph &g, CapacityMap& capacity, 
+		  typename Graph::Node &s) {
+    NullMap<typename Graph::Edge, int> n;
+    readDimacs(is, g, capacity, s, s, n);
+  }
+
+
+  /// Dimacs capacitated graph reader function.
+
+  /// This function reads an edge capacitated graph instance from
+  /// dimacs format.  At the beginning \c g is cleared by \c g.clear()
+  /// and the edge capacities are written to \c capacity.
+  ///
+  /// \author Marton Makai
+  template<typename Graph, typename CapacityMap>
+  void readDimacs(std::istream& is, Graph &g, CapacityMap& capacity) {
+    typename Graph::Node u;
+    NullMap<typename Graph::Edge, int> n;
+    readDimacs(is, g, capacity, u, u, n);
+  }
+
+
+  /// Dimacs plain graph reader function.
+
+  /// This function reads a graph without any designated nodes and
+  /// maps from dimacs format, i.e. from dimacs files having a line
+  /// starting with
+  /// \code
+  /// p "mat"
+  /// \endcode
+  /// At the beginning \c g is cleared
+  /// by \c g.clear().
+  ///
+  /// \author Marton Makai
+  template<typename Graph>
+  void readDimacs(std::istream& is, Graph &g) {
+    typename Graph::Node u;
+    NullMap<typename Graph::Edge, int> n;
+    readDimacs(is, g, n, u, u, n);
+  }
+  
+
+
+  
+  /// write matching problem
+  template<typename Graph>
+  void writeDimacs(std::ostream& os, const Graph &g) {
+    typedef typename Graph::NodeIt NodeIt;
+    typedef typename Graph::EdgeIt EdgeIt;  
+    
+    typename Graph::template NodeMap<int> nodes(g);
+
+    os << "c matching problem" << std::endl;
+
+    int i=1;
+    for(NodeIt v(g); v!=INVALID; ++v) {
+      nodes.set(v, i);
+      ++i;
+    }    
+    
+    os << "p mat " << g.nodeNum() << " " << g.edgeNum() << std::endl;
+
+    for(EdgeIt e(g); e!=INVALID; ++e) {
+      os << "a " << nodes[g.source(e)] << " " << nodes[g.target(e)] << std::endl; 
+    }
+
+  }
+
+  /// @}
+
+} //namespace lemon
+
+#endif //LEMON_DIMACS_H