gravatar
kpeter (Peter Kovacs)
kpeter@inf.elte.hu
Improvements in the heap concept - Better concept checking. - Improved doc.
0 1 0
default
1 file changed with 96 insertions and 71 deletions:
↑ Collapse diff ↑
Show white space 6 line context
... ...
@@ -18,8 +18,7 @@
18 18

	
19 19
///\ingroup concept
20 20
///\file
21
///\brief Classes for representing heaps.
22
///
21
///\brief The concept of heaps.
23 22

	
24 23
#ifndef LEMON_CONCEPT_HEAP_H
25 24
#define LEMON_CONCEPT_HEAP_H
... ...
@@ -27,31 +26,34 @@
27 26
#include <lemon/bits/invalid.h>
28 27

	
29 28
namespace lemon {
29

	
30 30
  namespace concepts {
31

	
31 32
    /// \addtogroup concept
32 33
    /// @{
33 34

	
34

	
35
    /// \brief A concept structure describes the main interface of heaps.
35
    /// \brief The heap concept.
36 36
    ///
37
    /// A concept structure describes the main interface of heaps.
38
    ///
39
    template <typename Prio, typename ItemIntMap>
37
    /// Concept class describing the main interface of heaps.
38
    template <typename Priority, typename ItemIntMap>
40 39
    class Heap {
41 40
    public:
42 41

	
43
      ///\brief Type of the items stored in the heap.
42
      /// Type of the items stored in the heap.
44 43
      typedef typename ItemIntMap::Key  Item;
45 44
  
45
      /// Type of the priorities.
46
      typedef Priority Prio;
46 47

	
47
      /// \brief Type to represent the items states.
48
      /// \brief Type to represent the states of the items.
48 49
      ///
49
      /// Each Item element have a state associated to it. It may be "in heap",
50
      /// "pre heap" or "post heap". The later two are indifferent from the
51
      /// heap's point of view, but may be useful to the user.
50
      /// Each item has a state associated to it. It can be "in heap",
51
      /// "pre heap" or "post heap". The later two are indifferent
52
      /// from the point of view of the heap, but may be useful for
53
      /// the user.
52 54
      ///
53
      /// The ItemIntMap _should_ be initialized in such way, that it maps
54
      /// PRE_HEAP (-1) to any element to be put in the heap...
55
      /// The \c ItemIntMap must be initialized in such a way, that it 
56
      /// assigns \c PRE_HEAP (<tt>-1</tt>) to every item.
55 57
      enum State {
56 58
	IN_HEAP = 0,
57 59
	PRE_HEAP = -1,
... ...
@@ -61,106 +63,108 @@
61 63
      /// \brief The constructor.
62 64
      ///
63 65
      /// The constructor.
64
      /// \param _iim should be given to the constructor, since it is used
65
      /// internally to handle the cross references. The value of the map
66
      /// should be PRE_HEAP (-1) for each element.
67
      explicit Heap(ItemIntMap &_iim) {}
66
      /// \param map A map that assigns \c int values to keys of type
67
      /// \c Item. It is used internally by the heap implementations to
68
      /// handle the cross references. The assigned value must be
69
      /// \c PRE_HEAP (<tt>-1</tt>) for every item.
70
      explicit Heap(ItemIntMap &map) {}
68 71

	
69 72
      /// \brief The number of items stored in the heap.
70 73
      ///
71 74
      /// Returns the number of items stored in the heap.
72 75
      int size() const { return 0; }
73 76

	
74
      /// \brief Checks if the heap stores no items.
77
      /// \brief Checks if the heap is empty.
75 78
      ///
76
      /// Returns \c true if and only if the heap stores no items.
79
      /// Returns \c true if the heap is empty.
77 80
      bool empty() const { return false; }
78 81

	
79
      /// \brief Makes empty this heap.
82
      /// \brief Makes the heap empty.
80 83
      ///
81
      /// Makes this heap empty.
84
      /// Makes the heap empty.
82 85
      void clear();
83 86

	
84
      /// \brief Insert an item into the heap with the given heap.
87
      /// \brief Inserts an item into the heap with the given priority.
85 88
      ///    
86
      /// Adds \c i to the heap with priority \c p. 
89
      /// Inserts the given item into the heap with the given priority. 
87 90
      /// \param i The item to insert.
88 91
      /// \param p The priority of the item.
89 92
      void push(const Item &i, const Prio &p) {}
90 93

	
91
      /// \brief Returns the item with minimum priority.
94
      /// \brief Returns the item having minimum priority.
92 95
      ///
93
      /// This method returns the item with minimum priority.  
94
      /// \pre The heap must be nonempty.  
96
      /// Returns the item having minimum priority.
97
      /// \pre The heap must be non-empty.
95 98
      Item top() const {}
96 99

	
97
      /// \brief Returns the minimum priority.
100
      /// \brief The minimum priority.
98 101
      ///
99
      /// It returns the minimum priority.
100
      /// \pre The heap must be nonempty.
102
      /// Returns the minimum priority.
103
      /// \pre The heap must be non-empty.
101 104
      Prio prio() const {}
102 105

	
103
      /// \brief Deletes the item with minimum priority.
106
      /// \brief Removes the item having minimum priority.
104 107
      ///
105
      /// This method deletes the item with minimum priority.
108
      /// Removes the item having minimum priority.
106 109
      /// \pre The heap must be non-empty.  
107 110
      void pop() {}
108 111

	
109
      /// \brief Deletes \c i from the heap.
112
      /// \brief Removes an item from the heap.
110 113
      ///
111
      /// This method deletes item \c i from the heap, if \c i was
112
      /// already stored in the heap.
113
      /// \param i The item to erase. 
114
      /// Removes the given item from the heap if it is already stored.
115
      /// \param i The item to delete. 
114 116
      void erase(const Item &i) {}
115 117

	
116
      /// \brief Returns the priority of \c i.
118
      /// \brief The priority of an item.
117 119
      ///
118
      /// This function returns the priority of item \c i.  
120
      /// Returns the priority of the given item.  
119 121
      /// \pre \c i must be in the heap.
120 122
      /// \param i The item.
121 123
      Prio operator[](const Item &i) const {}
122 124

	
123
      /// \brief \c i gets to the heap with priority \c p independently 
124
      /// if \c i was already there.
125
      /// \brief Sets the priority of an item or inserts it, if it is
126
      /// not stored in the heap.
125 127
      ///
126
      /// This method calls \ref push(\c i, \c p) if \c i is not stored
127
      /// in the heap and sets the priority of \c i to \c p otherwise.
128
      /// It may throw an \e UnderFlowPriorityException. 
128
      /// This method sets the priority of the given item if it is
129
      /// already stored in the heap.
130
      /// Otherwise it inserts the given item with the given priority.
131
      ///
132
      /// It may throw an \ref UnderflowPriorityException.
129 133
      /// \param i The item.
130 134
      /// \param p The priority.
131 135
      void set(const Item &i, const Prio &p) {}
132 136
      
133
      /// \brief Decreases the priority of \c i to \c p.
137
      /// \brief Decreases the priority of an item to the given value.
134 138
      ///
135
      /// This method decreases the priority of item \c i to \c p.
139
      /// Decreases the priority of an item to the given value.
136 140
      /// \pre \c i must be stored in the heap with priority at least \c p.
137 141
      /// \param i The item.
138 142
      /// \param p The priority.
139 143
      void decrease(const Item &i, const Prio &p) {}
140 144

	
141
      /// \brief Increases the priority of \c i to \c p.
145
      /// \brief Increases the priority of an item to the given value.
142 146
      ///
143
      /// This method sets the priority of item \c i to \c p. 
144
      /// \pre \c i must be stored in the heap with priority at most \c
145
      /// p relative to \c Compare.
147
      /// Increases the priority of an item to the given value.
148
      /// \pre \c i must be stored in the heap with priority at most \c p.
146 149
      /// \param i The item.
147 150
      /// \param p The priority.
148 151
      void increase(const Item &i, const Prio &p) {}
149 152

	
150
      /// \brief Returns if \c item is in, has already been in, or has 
153
      /// \brief Returns if an item is in, has already been in, or has
151 154
      /// never been in the heap.
152 155
      ///
153
      /// This method returns PRE_HEAP if \c item has never been in the
154
      /// heap, IN_HEAP if it is in the heap at the moment, and POST_HEAP
155
      /// otherwise. In the latter case it is possible that \c item will
156
      /// get back to the heap again.
156
      /// This method returns \c PRE_HEAP if the given item has never
157
      /// been in the heap, \c IN_HEAP if it is in the heap at the moment,
158
      /// and \c POST_HEAP otherwise.
159
      /// In the latter case it is possible that the item will get back
160
      /// to the heap again.
157 161
      /// \param i The item.
158 162
      State state(const Item &i) const {}
159 163

	
160
      /// \brief Sets the state of the \c item in the heap.
164
      /// \brief Sets the state of an item in the heap.
161 165
      ///
162
      /// Sets the state of the \c item in the heap. It can be used to
163
      /// manually clear the heap when it is important to achive the
166
      /// Sets the state of the given item in the heap. It can be used
167
      /// to manually clear the heap when it is important to achive the
164 168
      /// better time complexity.
165 169
      /// \param i The item.
166 170
      /// \param st The state. It should not be \c IN_HEAP. 
... ...
@@ -170,53 +174,74 @@
170 174
      template <typename _Heap>
171 175
      struct Constraints {
172 176
      public:
177
	void constraints() {
178
	  typedef typename _Heap::Item OwnItem;
179
	  typedef typename _Heap::Prio OwnPrio;
180
	  typedef typename _Heap::State OwnState;
173 181
    
174
	void constraints() {
175 182
	  Item item;
176 183
	  Prio prio;
177

	
184
	  State state;
178 185
	  item=Item();
179 186
	  prio=Prio();
180

	
181 187
	  ignore_unused_variable_warning(item);
182 188
	  ignore_unused_variable_warning(prio);
183

	
184
	  typedef typename _Heap::State State;
185
	  State state;
186

	
187 189
	  ignore_unused_variable_warning(state);
188 190
      
189
	  _Heap heap1 = _Heap(map);
191
	  OwnItem own_item;
192
	  OwnPrio own_prio;
193
	  OwnState own_state;
194
	  own_item=Item();
195
	  own_prio=Prio();
196
	  ignore_unused_variable_warning(own_item);
197
	  ignore_unused_variable_warning(own_prio);
198
	  ignore_unused_variable_warning(own_state);
190 199

	
200
	  _Heap heap1(map);
201
	  _Heap heap2 = heap1;
191 202
	  ignore_unused_variable_warning(heap1);
203
	  ignore_unused_variable_warning(heap2);
192 204
      
193
	  heap.push(item, prio);
205
	  int s = heap.size();
206
	  bool e = heap.empty();
194 207

	
195 208
	  prio = heap.prio();
196 209
	  item = heap.top();
210
	  prio = heap[item];
211
	  own_prio = heap.prio();
212
	  own_item = heap.top();
213
	  own_prio = heap[own_item];
197 214

	
215
	  heap.push(item, prio);
216
	  heap.push(own_item, own_prio);
198 217
	  heap.pop();
199 218

	
200 219
	  heap.set(item, prio);
201 220
	  heap.decrease(item, prio);
202 221
	  heap.increase(item, prio);
203
	  prio = heap[item];
222
	  heap.set(own_item, own_prio);
223
	  heap.decrease(own_item, own_prio);
224
	  heap.increase(own_item, own_prio);
204 225

	
205 226
	  heap.erase(item);
227
	  heap.erase(own_item);
228
	  heap.clear();
206 229

	
207 230
	  state = heap.state(item);
231
	  heap.state(item, state);
232
	  state = heap.state(own_item);
233
	  heap.state(own_item, own_state);
208 234

	
209 235
	  state = _Heap::PRE_HEAP;
210 236
	  state = _Heap::IN_HEAP;
211 237
	  state = _Heap::POST_HEAP;
212

	
213
	  heap.clear();
238
	  own_state = _Heap::PRE_HEAP;
239
	  own_state = _Heap::IN_HEAP;
240
	  own_state = _Heap::POST_HEAP;
214 241
	}
215 242
    
216 243
	_Heap& heap;
217 244
	ItemIntMap& map;
218

	
219
	Constraints() : heap(0), map(0) {}
220 245
      };
221 246
    };
222 247

	
0 comments (0 inline)