# HG changeset patch
# User Peter Kovacs <kpeter@inf.elte.hu>
# Date 1225917388 -3600
# Node ID b4a01426c0d9bda0adf39145368a7e76f4f35083
# Parent  3fb8ed1322de7eb738605582ff668a1ba0120d62
Port hypercube digraph structure from SVN 3503 (#57)

diff -r 3fb8ed1322de -r b4a01426c0d9 lemon/Makefile.am
--- a/lemon/Makefile.am	Tue Nov 04 10:25:47 2008 +0000
+++ b/lemon/Makefile.am	Wed Nov 05 21:36:28 2008 +0100
@@ -31,6 +31,7 @@
 	lemon/full_graph.h \
         lemon/graph_to_eps.h \
         lemon/grid_graph.h \
+	lemon/hypercube_graph.h \
 	lemon/kruskal.h \
 	lemon/lgf_reader.h \
 	lemon/lgf_writer.h \
diff -r 3fb8ed1322de -r b4a01426c0d9 lemon/hypercube_graph.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lemon/hypercube_graph.h	Wed Nov 05 21:36:28 2008 +0100
@@ -0,0 +1,316 @@
+/* -*- mode: C++; indent-tabs-mode: nil; -*-
+ *
+ * This file is a part of LEMON, a generic C++ optimization library.
+ *
+ * Copyright (C) 2003-2008
+ * 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 HYPERCUBE_GRAPH_H
+#define HYPERCUBE_GRAPH_H
+
+#include <iostream>
+#include <vector>
+#include <lemon/core.h>
+#include <lemon/error.h>
+
+#include <lemon/bits/base_extender.h>
+#include <lemon/bits/graph_extender.h>
+
+///\ingroup graphs
+///\file
+///\brief HypercubeDigraph class.
+
+namespace lemon {
+
+  class HypercubeDigraphBase {
+
+  public:
+
+    typedef HypercubeDigraphBase Digraph;
+
+    class Node;
+    class Arc;
+
+  public:
+
+    HypercubeDigraphBase() {}
+
+  protected:
+
+    void construct(int dim) {
+      _dim = dim;
+      _nodeNum = 1 << dim;
+    }
+
+  public:
+
+    typedef True NodeNumTag;
+    typedef True ArcNumTag;
+
+    int nodeNum() const { return _nodeNum; }
+    int arcNum() const { return _nodeNum * _dim; }
+
+    int maxNodeId() const { return nodeNum() - 1; }
+    int maxArcId() const { return arcNum() - 1; }
+
+    Node source(Arc e) const {
+      return e.id / _dim;
+    }
+
+    Node target(Arc e) const {
+      return (e.id / _dim) ^ (1 << (e.id % _dim));
+    }
+
+    static int id(Node v) { return v.id; }
+    static int id(Arc e) { return e.id; }
+
+    static Node nodeFromId(int id) { return Node(id); }
+
+    static Arc arcFromId(int id) { return Arc(id); }
+
+    class Node {
+      friend class HypercubeDigraphBase;
+    protected:
+      int id;
+      Node(int _id) { id = _id;}
+    public:
+      Node() {}
+      Node (Invalid) { id = -1; }
+      bool operator==(const Node node) const { return id == node.id; }
+      bool operator!=(const Node node) const { return id != node.id; }
+      bool operator<(const Node node) const { return id < node.id; }
+    };
+
+    class Arc {
+      friend class HypercubeDigraphBase;
+    protected:
+      int id;
+      Arc(int _id) : id(_id) {}
+    public:
+      Arc() { }
+      Arc (Invalid) { id = -1; }
+      bool operator==(const Arc arc) const { return id == arc.id; }
+      bool operator!=(const Arc arc) const { return id != arc.id; }
+      bool operator<(const Arc arc) const { return id < arc.id; }
+    };
+
+    void first(Node& node) const {
+      node.id = nodeNum() - 1;
+    }
+
+    static void next(Node& node) {
+      --node.id;
+    }
+
+    void first(Arc& arc) const {
+      arc.id = arcNum() - 1;
+    }
+
+    static void next(Arc& arc) {
+      --arc.id;
+    }
+
+    void firstOut(Arc& arc, const Node& node) const {
+      arc.id = node.id * _dim;
+    }
+
+    void nextOut(Arc& arc) const {
+      ++arc.id;
+      if (arc.id % _dim == 0) arc.id = -1;
+    }
+
+    void firstIn(Arc& arc, const Node& node) const {
+      arc.id = (node.id ^ 1) * _dim;
+    }
+
+    void nextIn(Arc& arc) const {
+      int cnt = arc.id % _dim;
+      if ((cnt + 1) % _dim == 0) {
+        arc.id = -1;
+      } else {
+        arc.id = ((arc.id / _dim) ^ ((1 << cnt) * 3)) * _dim + cnt + 1;
+      }
+    }
+
+    int dimension() const {
+      return _dim;
+    }
+
+    bool projection(Node node, int n) const {
+      return static_cast<bool>(node.id & (1 << n));
+    }
+
+    int dimension(Arc arc) const {
+      return arc.id % _dim;
+    }
+
+    int index(Node node) const {
+      return node.id;
+    }
+
+    Node operator()(int ix) const {
+      return Node(ix);
+    }
+
+  private:
+    int _dim, _nodeNum;
+  };
+
+
+  typedef DigraphExtender<HypercubeDigraphBase> ExtendedHypercubeDigraphBase;
+
+  /// \ingroup digraphs
+  ///
+  /// \brief Hypercube digraph class
+  ///
+  /// This class implements a special digraph type. The nodes of the
+  /// digraph are indiced with integers with at most \c dim binary digits.
+  /// Two nodes are connected in the digraph if the indices differ only
+  /// on one position in the binary form.
+  ///
+  /// \note The type of the \c ids is chosen to \c int because efficiency
+  /// reasons. Thus the maximum dimension of this implementation is 26.
+  ///
+  /// The digraph type is fully conform to the \ref concepts::Digraph
+  /// concept but it does not conform to \ref concepts::Graph.
+  class HypercubeDigraph : public ExtendedHypercubeDigraphBase {
+  public:
+
+    typedef ExtendedHypercubeDigraphBase Parent;
+
+    /// \brief Construct a hypercube digraph with \c dim dimension.
+    ///
+    /// Construct a hypercube digraph with \c dim dimension.
+    HypercubeDigraph(int dim) { construct(dim); }
+
+    /// \brief Gives back the number of the dimensions.
+    ///
+    /// Gives back the number of the dimensions.
+    int dimension() const {
+      return Parent::dimension();
+    }
+
+    /// \brief Returns true if the n'th bit of the node is one.
+    ///
+    /// Returns true if the n'th bit of the node is one.
+    bool projection(Node node, int n) const {
+      return Parent::projection(node, n);
+    }
+
+    /// \brief The dimension id of the arc.
+    ///
+    /// It returns the dimension id of the arc. It can
+    /// be in the \f$ \{0, 1, \dots, dim-1\} \f$ interval.
+    int dimension(Arc arc) const {
+      return Parent::dimension(arc);
+    }
+
+    /// \brief Gives back the index of the node.
+    ///
+    /// Gives back the index of the node. The lower bits of the
+    /// integer describes the node.
+    int index(Node node) const {
+      return Parent::index(node);
+    }
+
+    /// \brief Gives back the node by its index.
+    ///
+    /// Gives back the node by its index.
+    Node operator()(int ix) const {
+      return Parent::operator()(ix);
+    }
+
+    /// \brief Number of nodes.
+    int nodeNum() const { return Parent::nodeNum(); }
+    /// \brief Number of arcs.
+    int arcNum() const { return Parent::arcNum(); }
+
+    /// \brief Linear combination map.
+    ///
+    /// It makes possible to give back a linear combination
+    /// for each node. This function works like the \c std::accumulate
+    /// so it accumulates the \c bf binary function with the \c fv
+    /// first value. The map accumulates only on that dimensions where
+    /// the node's index is one. The accumulated values should be
+    /// given by the \c begin and \c end iterators and the length of this
+    /// range should be equal to the dimension number of the digraph.
+    ///
+    ///\code
+    /// const int DIM = 3;
+    /// HypercubeDigraph digraph(DIM);
+    /// dim2::Point<double> base[DIM];
+    /// for (int k = 0; k < DIM; ++k) {
+    ///   base[k].x = rnd();
+    ///   base[k].y = rnd();
+    /// }
+    /// HypercubeDigraph::HyperMap<dim2::Point<double> >
+    ///   pos(digraph, base, base + DIM, dim2::Point<double>(0.0, 0.0));
+    ///\endcode
+    ///
+    /// \see HypercubeDigraph
+    template <typename T, typename BF = std::plus<T> >
+    class HyperMap {
+    public:
+
+      typedef Node Key;
+      typedef T Value;
+
+
+      /// \brief Constructor for HyperMap.
+      ///
+      /// Construct a HyperMap for the given digraph. The accumulated values
+      /// should be given by the \c begin and \c end iterators and the length
+      /// of this range should be equal to the dimension number of the digraph.
+      ///
+      /// This function accumulates the \c bf binary function with
+      /// the \c fv first value. The map accumulates only on that dimensions
+      /// where the node's index is one.
+      template <typename It>
+      HyperMap(const Digraph& digraph, It begin, It end,
+               T fv = 0.0, const BF& bf = BF())
+        : _graph(digraph), _values(begin, end), _first_value(fv), _bin_func(bf)
+      {
+        LEMON_ASSERT(_values.size() == digraph.dimension(),
+                     "Wrong size of dimension");
+      }
+
+      /// \brief Gives back the partial accumulated value.
+      ///
+      /// Gives back the partial accumulated value.
+      Value operator[](Key k) const {
+        Value val = _first_value;
+        int id = _graph.index(k);
+        int n = 0;
+        while (id != 0) {
+          if (id & 1) {
+            val = _bin_func(val, _values[n]);
+          }
+          id >>= 1;
+          ++n;
+        }
+        return val;
+      }
+
+    private:
+      const Digraph& _graph;
+      std::vector<T> _values;
+      T _first_value;
+      BF _bin_func;
+    };
+
+  };
+
+}
+
+#endif
diff -r 3fb8ed1322de -r b4a01426c0d9 test/digraph_test.cc
--- a/test/digraph_test.cc	Tue Nov 04 10:25:47 2008 +0000
+++ b/test/digraph_test.cc	Wed Nov 05 21:36:28 2008 +0100
@@ -20,7 +20,7 @@
 #include <lemon/list_graph.h>
 #include <lemon/smart_graph.h>
 #include <lemon/full_graph.h>
-//#include <lemon/hypercube_graph.h>
+#include <lemon/hypercube_graph.h>
 
 #include "test_tools.h"
 #include "graph_test.h"
@@ -112,6 +112,35 @@
 
 }
 
+void checkHypercubeDigraph(int dim) {
+  DIGRAPH_TYPEDEFS(HypercubeDigraph);
+
+  HypercubeDigraph G(dim);
+  checkGraphNodeList(G, 1 << dim);
+  checkGraphArcList(G, (1 << dim) * dim);
+
+  Node n = G.nodeFromId(dim);
+
+  checkGraphOutArcList(G, n, dim);
+  for (OutArcIt a(G, n); a != INVALID; ++a)
+    check(G.source(a) == n &&
+          G.id(G.target(a)) == G.id(n) ^ (1 << G.dimension(a)),
+          "Wrong arc");
+
+  checkGraphInArcList(G, n, dim);
+  for (InArcIt a(G, n); a != INVALID; ++a)
+    check(G.target(a) == n &&
+          G.id(G.source(a)) == G.id(n) ^ (1 << G.dimension(a)),
+          "Wrong arc");
+
+  checkGraphConArcList(G, (1 << dim) * dim);
+
+  checkNodeIds(G);
+  checkArcIds(G);
+  checkGraphNodeMap(G);
+  checkGraphArcMap(G);
+}
+
 
 void checkConcepts() {
   { // Checking digraph components
@@ -145,9 +174,9 @@
   { // Checking FullDigraph
     checkConcept<Digraph, FullDigraph>();
   }
-//  { // Checking HyperCubeDigraph
-//    checkConcept<Digraph, HyperCubeDigraph>();
-//  }
+  { // Checking HypercubeDigraph
+    checkConcept<Digraph, HypercubeDigraph>();
+  }
 }
 
 template <typename Digraph>
@@ -212,6 +241,12 @@
   { // Checking FullDigraph
     checkFullDigraph(8);
   }
+  { // Checking HypercubeDigraph
+    checkHypercubeDigraph(1);
+    checkHypercubeDigraph(2);
+    checkHypercubeDigraph(3);
+    checkHypercubeDigraph(4);
+  }
 }
 
 int main() {