lemon/bits/vector_map.h
author Akos Ladanyi <ladanyi@tmit.bme.hu>
Thu, 22 Jan 2009 10:39:56 +0000
changeset 476 f9a879c9787c
parent 280 e7f8647ce760
child 361 f58410582b9b
permissions -rw-r--r--
Update the lemon icon
     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 LEMON_BITS_VECTOR_MAP_H
    20 #define LEMON_BITS_VECTOR_MAP_H
    21 
    22 #include <vector>
    23 #include <algorithm>
    24 
    25 #include <lemon/core.h>
    26 #include <lemon/bits/alteration_notifier.h>
    27 
    28 #include <lemon/concept_check.h>
    29 #include <lemon/concepts/maps.h>
    30 
    31 //\ingroup graphbits
    32 //
    33 //\file
    34 //\brief Vector based graph maps.
    35 namespace lemon {
    36 
    37   // \ingroup graphbits
    38   //
    39   // \brief Graph map based on the std::vector storage.
    40   //
    41   // The VectorMap template class is graph map structure what
    42   // automatically updates the map when a key is added to or erased from
    43   // the map. This map type uses the std::vector to store the values.
    44   //
    45   // \tparam _Graph The graph this map is attached to.
    46   // \tparam _Item The item type of the graph items.
    47   // \tparam _Value The value type of the map.
    48   template <typename _Graph, typename _Item, typename _Value>
    49   class VectorMap
    50     : public ItemSetTraits<_Graph, _Item>::ItemNotifier::ObserverBase {
    51   private:
    52 
    53     // The container type of the map.
    54     typedef std::vector<_Value> Container;
    55 
    56   public:
    57 
    58     // The graph type of the map.
    59     typedef _Graph Graph;
    60     // The item type of the map.
    61     typedef _Item Item;
    62     // The reference map tag.
    63     typedef True ReferenceMapTag;
    64 
    65     // The key type of the map.
    66     typedef _Item Key;
    67     // The value type of the map.
    68     typedef _Value Value;
    69 
    70     // The notifier type.
    71     typedef typename ItemSetTraits<_Graph, _Item>::ItemNotifier Notifier;
    72 
    73     // The map type.
    74     typedef VectorMap Map;
    75     // The base class of the map.
    76     typedef typename Notifier::ObserverBase Parent;
    77 
    78     // The reference type of the map;
    79     typedef typename Container::reference Reference;
    80     // The const reference type of the map;
    81     typedef typename Container::const_reference ConstReference;
    82 
    83 
    84     // \brief Constructor to attach the new map into the notifier.
    85     //
    86     // It constructs a map and attachs it into the notifier.
    87     // It adds all the items of the graph to the map.
    88     VectorMap(const Graph& graph) {
    89       Parent::attach(graph.notifier(Item()));
    90       container.resize(Parent::notifier()->maxId() + 1);
    91     }
    92 
    93     // \brief Constructor uses given value to initialize the map.
    94     //
    95     // It constructs a map uses a given value to initialize the map.
    96     // It adds all the items of the graph to the map.
    97     VectorMap(const Graph& graph, const Value& value) {
    98       Parent::attach(graph.notifier(Item()));
    99       container.resize(Parent::notifier()->maxId() + 1, value);
   100     }
   101 
   102   private:
   103     // \brief Copy constructor
   104     //
   105     // Copy constructor.
   106     VectorMap(const VectorMap& _copy) : Parent() {
   107       if (_copy.attached()) {
   108         Parent::attach(*_copy.notifier());
   109         container = _copy.container;
   110       }
   111     }
   112 
   113     // \brief Assign operator.
   114     //
   115     // This operator assigns for each item in the map the
   116     // value mapped to the same item in the copied map.
   117     // The parameter map should be indiced with the same
   118     // itemset because this assign operator does not change
   119     // the container of the map.
   120     VectorMap& operator=(const VectorMap& cmap) {
   121       return operator=<VectorMap>(cmap);
   122     }
   123 
   124 
   125     // \brief Template assign operator.
   126     //
   127     // The given parameter should be conform to the ReadMap
   128     // concecpt and could be indiced by the current item set of
   129     // the NodeMap. In this case the value for each item
   130     // is assigned by the value of the given ReadMap.
   131     template <typename CMap>
   132     VectorMap& operator=(const CMap& cmap) {
   133       checkConcept<concepts::ReadMap<Key, _Value>, CMap>();
   134       const typename Parent::Notifier* nf = Parent::notifier();
   135       Item it;
   136       for (nf->first(it); it != INVALID; nf->next(it)) {
   137         set(it, cmap[it]);
   138       }
   139       return *this;
   140     }
   141 
   142   public:
   143 
   144     // \brief The subcript operator.
   145     //
   146     // The subscript operator. The map can be subscripted by the
   147     // actual items of the graph.
   148     Reference operator[](const Key& key) {
   149       return container[Parent::notifier()->id(key)];
   150     }
   151 
   152     // \brief The const subcript operator.
   153     //
   154     // The const subscript operator. The map can be subscripted by the
   155     // actual items of the graph.
   156     ConstReference operator[](const Key& key) const {
   157       return container[Parent::notifier()->id(key)];
   158     }
   159 
   160 
   161     // \brief The setter function of the map.
   162     //
   163     // It the same as operator[](key) = value expression.
   164     void set(const Key& key, const Value& value) {
   165       (*this)[key] = value;
   166     }
   167 
   168   protected:
   169 
   170     // \brief Adds a new key to the map.
   171     //
   172     // It adds a new key to the map. It called by the observer notifier
   173     // and it overrides the add() member function of the observer base.
   174     virtual void add(const Key& key) {
   175       int id = Parent::notifier()->id(key);
   176       if (id >= int(container.size())) {
   177         container.resize(id + 1);
   178       }
   179     }
   180 
   181     // \brief Adds more new keys to the map.
   182     //
   183     // It adds more new keys to the map. It called by the observer notifier
   184     // and it overrides the add() member function of the observer base.
   185     virtual void add(const std::vector<Key>& keys) {
   186       int max = container.size() - 1;
   187       for (int i = 0; i < int(keys.size()); ++i) {
   188         int id = Parent::notifier()->id(keys[i]);
   189         if (id >= max) {
   190           max = id;
   191         }
   192       }
   193       container.resize(max + 1);
   194     }
   195 
   196     // \brief Erase a key from the map.
   197     //
   198     // Erase a key from the map. It called by the observer notifier
   199     // and it overrides the erase() member function of the observer base.
   200     virtual void erase(const Key& key) {
   201       container[Parent::notifier()->id(key)] = Value();
   202     }
   203 
   204     // \brief Erase more keys from the map.
   205     //
   206     // Erase more keys from the map. It called by the observer notifier
   207     // and it overrides the erase() member function of the observer base.
   208     virtual void erase(const std::vector<Key>& keys) {
   209       for (int i = 0; i < int(keys.size()); ++i) {
   210         container[Parent::notifier()->id(keys[i])] = Value();
   211       }
   212     }
   213 
   214     // \brief Buildes the map.
   215     //
   216     // It buildes the map. It called by the observer notifier
   217     // and it overrides the build() member function of the observer base.
   218     virtual void build() {
   219       int size = Parent::notifier()->maxId() + 1;
   220       container.reserve(size);
   221       container.resize(size);
   222     }
   223 
   224     // \brief Clear the map.
   225     //
   226     // It erase all items from the map. It called by the observer notifier
   227     // and it overrides the clear() member function of the observer base.
   228     virtual void clear() {
   229       container.clear();
   230     }
   231 
   232   private:
   233 
   234     Container container;
   235 
   236   };
   237 
   238 }
   239 
   240 #endif