| | 1 | /* -*- mode: C++; indent-tabs-mode: nil; -*- |
| | 2 | * |
| | 3 | * This file is a part of LEMON, a generic C++ optimization library. |
| | 4 | * |
| | 5 | * Copyright (C) 2003-2008 |
| | 6 | * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
| | 7 | * (Egervary Research Group on Combinatorial Optimization, EGRES). |
| | 8 | * |
| | 9 | * Permission to use, modify and distribute this software is granted |
| | 10 | * provided that this copyright notice appears in all copies. For |
| | 11 | * precise terms see the accompanying LICENSE file. |
| | 12 | * |
| | 13 | * This software is provided "AS IS" with no warranty of any kind, |
| | 14 | * express or implied, and with no claim as to its suitability for any |
| | 15 | * purpose. |
| | 16 | * |
| | 17 | */ |
| | 18 | |
| | 19 | #ifndef HYPERCUBE_GRAPH_H |
| | 20 | #define HYPERCUBE_GRAPH_H |
| | 21 | |
| | 22 | #include <iostream> |
| | 23 | #include <vector> |
| | 24 | #include <lemon/core.h> |
| | 25 | #include <lemon/error.h> |
| | 26 | |
| | 27 | #include <lemon/bits/base_extender.h> |
| | 28 | #include <lemon/bits/graph_extender.h> |
| | 29 | |
| | 30 | ///\ingroup graphs |
| | 31 | ///\file |
| | 32 | ///\brief HyperCubeDigraph class. |
| | 33 | |
| | 34 | namespace lemon { |
| | 35 | |
| | 36 | class HyperCubeDigraphBase { |
| | 37 | |
| | 38 | public: |
| | 39 | |
| | 40 | typedef HyperCubeDigraphBase Digraph; |
| | 41 | |
| | 42 | class Node; |
| | 43 | class Arc; |
| | 44 | |
| | 45 | public: |
| | 46 | |
| | 47 | HyperCubeDigraphBase() {} |
| | 48 | |
| | 49 | protected: |
| | 50 | |
| | 51 | void construct(int dim) { |
| | 52 | _dim = dim; |
| | 53 | _nodeNum = 1 << dim; |
| | 54 | } |
| | 55 | |
| | 56 | public: |
| | 57 | |
| | 58 | typedef True NodeNumTag; |
| | 59 | typedef True ArcNumTag; |
| | 60 | |
| | 61 | int nodeNum() const { return _nodeNum; } |
| | 62 | int arcNum() const { return _nodeNum * _dim; } |
| | 63 | |
| | 64 | int maxNodeId() const { return nodeNum() - 1; } |
| | 65 | int maxArcId() const { return arcNum() - 1; } |
| | 66 | |
| | 67 | Node source(Arc e) const { |
| | 68 | return e.id / _dim; |
| | 69 | } |
| | 70 | |
| | 71 | Node target(Arc e) const { |
| | 72 | return (e.id / _dim) ^ (1 << (e.id % _dim)); |
| | 73 | } |
| | 74 | |
| | 75 | static int id(Node v) { return v.id; } |
| | 76 | static int id(Arc e) { return e.id; } |
| | 77 | |
| | 78 | static Node nodeFromId(int id) { return Node(id); } |
| | 79 | |
| | 80 | static Arc arcFromId(int id) { return Arc(id); } |
| | 81 | |
| | 82 | class Node { |
| | 83 | friend class HyperCubeDigraphBase; |
| | 84 | protected: |
| | 85 | int id; |
| | 86 | Node(int _id) { id = _id;} |
| | 87 | public: |
| | 88 | Node() {} |
| | 89 | Node (Invalid) { id = -1; } |
| | 90 | bool operator==(const Node node) const { return id == node.id; } |
| | 91 | bool operator!=(const Node node) const { return id != node.id; } |
| | 92 | bool operator<(const Node node) const { return id < node.id; } |
| | 93 | }; |
| | 94 | |
| | 95 | class Arc { |
| | 96 | friend class HyperCubeDigraphBase; |
| | 97 | protected: |
| | 98 | int id; |
| | 99 | Arc(int _id) : id(_id) {} |
| | 100 | public: |
| | 101 | Arc() { } |
| | 102 | Arc (Invalid) { id = -1; } |
| | 103 | bool operator==(const Arc arc) const { return id == arc.id; } |
| | 104 | bool operator!=(const Arc arc) const { return id != arc.id; } |
| | 105 | bool operator<(const Arc arc) const { return id < arc.id; } |
| | 106 | }; |
| | 107 | |
| | 108 | void first(Node& node) const { |
| | 109 | node.id = nodeNum() - 1; |
| | 110 | } |
| | 111 | |
| | 112 | static void next(Node& node) { |
| | 113 | --node.id; |
| | 114 | } |
| | 115 | |
| | 116 | void first(Arc& arc) const { |
| | 117 | arc.id = arcNum() - 1; |
| | 118 | } |
| | 119 | |
| | 120 | static void next(Arc& arc) { |
| | 121 | --arc.id; |
| | 122 | } |
| | 123 | |
| | 124 | void firstOut(Arc& arc, const Node& node) const { |
| | 125 | arc.id = node.id * _dim; |
| | 126 | } |
| | 127 | |
| | 128 | void nextOut(Arc& arc) const { |
| | 129 | ++arc.id; |
| | 130 | if (arc.id % _dim == 0) arc.id = -1; |
| | 131 | } |
| | 132 | |
| | 133 | void firstIn(Arc& arc, const Node& node) const { |
| | 134 | arc.id = (node.id ^ 1) * _dim; |
| | 135 | } |
| | 136 | |
| | 137 | void nextIn(Arc& arc) const { |
| | 138 | int cnt = arc.id % _dim; |
| | 139 | if ((cnt + 1) % _dim == 0) { |
| | 140 | arc.id = -1; |
| | 141 | } else { |
| | 142 | arc.id = ((arc.id / _dim) ^ ((1 << cnt) * 3)) * _dim + cnt + 1; |
| | 143 | } |
| | 144 | } |
| | 145 | |
| | 146 | int dimension() const { |
| | 147 | return _dim; |
| | 148 | } |
| | 149 | |
| | 150 | bool projection(Node node, int n) const { |
| | 151 | return static_cast<bool>(node.id & (1 << n)); |
| | 152 | } |
| | 153 | |
| | 154 | int dimension(Arc arc) const { |
| | 155 | return arc.id % _dim; |
| | 156 | } |
| | 157 | |
| | 158 | int index(Node node) const { |
| | 159 | return node.id; |
| | 160 | } |
| | 161 | |
| | 162 | Node operator()(int ix) const { |
| | 163 | return Node(ix); |
| | 164 | } |
| | 165 | |
| | 166 | private: |
| | 167 | int _dim, _nodeNum; |
| | 168 | }; |
| | 169 | |
| | 170 | |
| | 171 | typedef DigraphExtender<HyperCubeDigraphBase> ExtendedHyperCubeDigraphBase; |
| | 172 | |
| | 173 | /// \ingroup digraphs |
| | 174 | /// |
| | 175 | /// \brief Hypercube digraph class |
| | 176 | /// |
| | 177 | /// This class implements a special digraph type. The nodes of the |
| | 178 | /// digraph are indiced with integers with at most \c dim binary digits. |
| | 179 | /// Two nodes are connected in the digraph if the indices differ only |
| | 180 | /// on one position in the binary form. |
| | 181 | /// |
| | 182 | /// \note The type of the \c ids is chosen to \c int because efficiency |
| | 183 | /// reasons. Thus the maximum dimension of this implementation is 26. |
| | 184 | /// |
| | 185 | /// The digraph type is fully conform to the \ref concepts::Digraph |
| | 186 | /// concept but it does not conform to \ref concepts::Graph. |
| | 187 | class HyperCubeDigraph : public ExtendedHyperCubeDigraphBase { |
| | 188 | public: |
| | 189 | |
| | 190 | typedef ExtendedHyperCubeDigraphBase Parent; |
| | 191 | |
| | 192 | /// \brief Construct a hypercube digraph with \c dim dimension. |
| | 193 | /// |
| | 194 | /// Construct a hypercube digraph with \c dim dimension. |
| | 195 | HyperCubeDigraph(int dim) { construct(dim); } |
| | 196 | |
| | 197 | /// \brief Gives back the number of the dimensions. |
| | 198 | /// |
| | 199 | /// Gives back the number of the dimensions. |
| | 200 | int dimension() const { |
| | 201 | return Parent::dimension(); |
| | 202 | } |
| | 203 | |
| | 204 | /// \brief Returns true if the n'th bit of the node is one. |
| | 205 | /// |
| | 206 | /// Returns true if the n'th bit of the node is one. |
| | 207 | bool projection(Node node, int n) const { |
| | 208 | return Parent::projection(node, n); |
| | 209 | } |
| | 210 | |
| | 211 | /// \brief The dimension id of the arc. |
| | 212 | /// |
| | 213 | /// It returns the dimension id of the arc. It can |
| | 214 | /// be in the \f$ \{0, 1, \dots, dim-1\} \f$ interval. |
| | 215 | int dimension(Arc arc) const { |
| | 216 | return Parent::dimension(arc); |
| | 217 | } |
| | 218 | |
| | 219 | /// \brief Gives back the index of the node. |
| | 220 | /// |
| | 221 | /// Gives back the index of the node. The lower bits of the |
| | 222 | /// integer describes the node. |
| | 223 | int index(Node node) const { |
| | 224 | return Parent::index(node); |
| | 225 | } |
| | 226 | |
| | 227 | /// \brief Gives back the node by its index. |
| | 228 | /// |
| | 229 | /// Gives back the node by its index. |
| | 230 | Node operator()(int ix) const { |
| | 231 | return Parent::operator()(ix); |
| | 232 | } |
| | 233 | |
| | 234 | /// \brief Number of nodes. |
| | 235 | int nodeNum() const { return Parent::nodeNum(); } |
| | 236 | /// \brief Number of arcs. |
| | 237 | int arcNum() const { return Parent::arcNum(); } |
| | 238 | |
| | 239 | /// \brief Linear combination map. |
| | 240 | /// |
| | 241 | /// It makes possible to give back a linear combination |
| | 242 | /// for each node. This function works like the \c std::accumulate |
| | 243 | /// so it accumulates the \c bf binary function with the \c fv |
| | 244 | /// first value. The map accumulates only on that dimensions where |
| | 245 | /// the node's index is one. The accumulated values should be |
| | 246 | /// given by the \c begin and \c end iterators and the length of this |
| | 247 | /// range should be equal to the dimension number of the digraph. |
| | 248 | /// |
| | 249 | ///\code |
| | 250 | /// const int DIM = 3; |
| | 251 | /// HyperCubeDigraph digraph(DIM); |
| | 252 | /// dim2::Point<double> base[DIM]; |
| | 253 | /// for (int k = 0; k < DIM; ++k) { |
| | 254 | /// base[k].x = rnd(); |
| | 255 | /// base[k].y = rnd(); |
| | 256 | /// } |
| | 257 | /// HyperCubeDigraph::HyperMap<dim2::Point<double> > |
| | 258 | /// pos(digraph, base, base + DIM, dim2::Point<double>(0.0, 0.0)); |
| | 259 | ///\endcode |
| | 260 | /// |
| | 261 | /// \see HyperCubeDigraph |
| | 262 | template <typename T, typename BF = std::plus<T> > |
| | 263 | class HyperMap { |
| | 264 | public: |
| | 265 | |
| | 266 | typedef Node Key; |
| | 267 | typedef T Value; |
| | 268 | |
| | 269 | |
| | 270 | /// \brief Constructor for HyperMap. |
| | 271 | /// |
| | 272 | /// Construct a HyperMap for the given digraph. The accumulated values |
| | 273 | /// should be given by the \c begin and \c end iterators and the length |
| | 274 | /// of this range should be equal to the dimension number of the digraph. |
| | 275 | /// |
| | 276 | /// This function accumulates the \c bf binary function with |
| | 277 | /// the \c fv first value. The map accumulates only on that dimensions |
| | 278 | /// where the node's index is one. |
| | 279 | template <typename It> |
| | 280 | HyperMap(const Digraph& digraph, It begin, It end, |
| | 281 | T fv = 0.0, const BF& bf = BF()) |
| | 282 | : _graph(digraph), _values(begin, end), _first_value(fv), _bin_func(bf) |
| | 283 | { |
| | 284 | LEMON_ASSERT(_values.size() == digraph.dimension(), |
| | 285 | "Wrong size of dimension"); |
| | 286 | } |
| | 287 | |
| | 288 | /// \brief Gives back the partial accumulated value. |
| | 289 | /// |
| | 290 | /// Gives back the partial accumulated value. |
| | 291 | Value operator[](Key k) const { |
| | 292 | Value val = _first_value; |
| | 293 | int id = _graph.index(k); |
| | 294 | int n = 0; |
| | 295 | while (id != 0) { |
| | 296 | if (id & 1) { |
| | 297 | val = _bin_func(val, _values[n]); |
| | 298 | } |
| | 299 | id >>= 1; |
| | 300 | ++n; |
| | 301 | } |
| | 302 | return val; |
| | 303 | } |
| | 304 | |
| | 305 | private: |
| | 306 | const Digraph& _graph; |
| | 307 | std::vector<T> _values; |
| | 308 | T _first_value; |
| | 309 | BF _bin_func; |
| | 310 | }; |
| | 311 | |
| | 312 | }; |
| | 313 | |
| | 314 | } |
| | 315 | |
| | 316 | #endif |