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/* -*- C++ -*- |
|
1 |
/* -*- mode: C++; indent-tabs-mode: nil; -*- |
|
2 | 2 |
* |
3 |
* This file is a part of LEMON, a generic C++ optimization library |
|
3 |
* This file is a part of LEMON, a generic C++ optimization library. |
|
4 | 4 |
* |
5 |
* Copyright (C) 2003- |
|
5 |
* Copyright (C) 2003-2009 |
|
6 | 6 |
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
7 | 7 |
* (Egervary Research Group on Combinatorial Optimization, EGRES). |
8 | 8 |
* |
... | ... |
@@ -20,193 +20,199 @@ |
20 | 20 |
#define LEMON_BINOM_HEAP_H |
21 | 21 |
|
22 | 22 |
///\file |
23 |
///\ingroup |
|
23 |
///\ingroup heaps |
|
24 | 24 |
///\brief Binomial Heap implementation. |
25 | 25 |
|
26 | 26 |
#include <vector> |
27 |
#include <utility> |
|
27 | 28 |
#include <functional> |
28 | 29 |
#include <lemon/math.h> |
29 | 30 |
#include <lemon/counter.h> |
30 | 31 |
|
31 | 32 |
namespace lemon { |
32 | 33 |
|
33 |
/// \ingroup |
|
34 |
/// \ingroup heaps |
|
34 | 35 |
/// |
35 |
///\brief Binomial |
|
36 |
///\brief Binomial heap data structure. |
|
36 | 37 |
/// |
37 |
///This class implements the \e Binomial \e heap data structure. A \e heap |
|
38 |
///is a data structure for storing items with specified values called \e |
|
39 |
///priorities in such a way that finding the item with minimum priority is |
|
40 |
///efficient. \c Compare specifies the ordering of the priorities. In a heap |
|
41 |
/// |
|
38 |
/// This class implements the \e binomial \e heap data structure. |
|
39 |
/// It fully conforms to the \ref concepts::Heap "heap concept". |
|
42 | 40 |
/// |
43 |
///The methods \ref increase and \ref erase are not efficient in a Binomial |
|
44 |
///heap. In case of many calls to these operations, it is better to use a |
|
45 |
///\ref |
|
41 |
/// The methods \ref increase() and \ref erase() are not efficient |
|
42 |
/// in a binomial heap. In case of many calls of these operations, |
|
43 |
/// it is better to use other heap structure, e.g. \ref BinHeap |
|
44 |
/// "binary heap". |
|
46 | 45 |
/// |
47 |
///\param _Prio Type of the priority of the items. |
|
48 |
///\param _ItemIntMap A read and writable Item int map, used internally |
|
49 |
///to handle the cross references. |
|
50 |
///\param _Compare A class for the ordering of the priorities. The |
|
51 |
///default is \c std::less<_Prio>. |
|
52 |
/// |
|
53 |
///\sa BinHeap |
|
54 |
///\sa Dijkstra |
|
55 |
///\author Dorian Batha |
|
56 |
|
|
46 |
/// \tparam PR Type of the priorities of the items. |
|
47 |
/// \tparam IM A read-writable item map with \c int values, used |
|
48 |
/// internally to handle the cross references. |
|
49 |
/// \tparam CMP A functor class for comparing the priorities. |
|
50 |
/// The default is \c std::less<PR>. |
|
57 | 51 |
#ifdef DOXYGEN |
58 |
template <typename _Prio, |
|
59 |
typename _ItemIntMap, |
|
60 |
|
|
52 |
template <typename PR, typename IM, typename CMP> |
|
61 | 53 |
#else |
62 |
template <typename _Prio, |
|
63 |
typename _ItemIntMap, |
|
64 |
|
|
54 |
template <typename PR, typename IM, typename CMP = std::less<PR> > |
|
65 | 55 |
#endif |
66 | 56 |
class BinomHeap { |
67 | 57 |
public: |
68 |
typedef _ItemIntMap ItemIntMap; |
|
69 |
typedef _Prio Prio; |
|
58 |
/// Type of the item-int map. |
|
59 |
typedef IM ItemIntMap; |
|
60 |
/// Type of the priorities. |
|
61 |
typedef PR Prio; |
|
62 |
/// Type of the items stored in the heap. |
|
70 | 63 |
typedef typename ItemIntMap::Key Item; |
71 |
typedef std::pair<Item,Prio> Pair; |
|
72 |
typedef _Compare Compare; |
|
64 |
/// Functor type for comparing the priorities. |
|
65 |
typedef CMP Compare; |
|
66 |
|
|
67 |
/// \brief Type to represent the states of the items. |
|
68 |
/// |
|
69 |
/// Each item has a state associated to it. It can be "in heap", |
|
70 |
/// "pre-heap" or "post-heap". The latter two are indifferent from the |
|
71 |
/// heap's point of view, but may be useful to the user. |
|
72 |
/// |
|
73 |
/// The item-int map must be initialized in such way that it assigns |
|
74 |
/// \c PRE_HEAP (<tt>-1</tt>) to any element to be put in the heap. |
|
75 |
enum State { |
|
76 |
IN_HEAP = 0, ///< = 0. |
|
77 |
PRE_HEAP = -1, ///< = -1. |
|
78 |
POST_HEAP = -2 ///< = -2. |
|
79 |
}; |
|
73 | 80 |
|
74 | 81 |
private: |
75 | 82 |
class store; |
76 | 83 |
|
77 |
std::vector<store> container; |
|
78 |
int minimum, head; |
|
79 |
ItemIntMap &iimap; |
|
80 |
Compare comp; |
|
81 |
|
|
84 |
std::vector<store> _data; |
|
85 |
int _min, _head; |
|
86 |
ItemIntMap &_iim; |
|
87 |
Compare _comp; |
|
88 |
int _num_items; |
|
82 | 89 |
|
83 | 90 |
public: |
84 |
///Status of the nodes |
|
85 |
enum State { |
|
86 |
///The node is in the heap |
|
87 |
IN_HEAP = 0, |
|
88 |
///The node has never been in the heap |
|
89 |
PRE_HEAP = -1, |
|
90 |
///The node was in the heap but it got out of it |
|
91 |
POST_HEAP = -2 |
|
92 |
|
|
91 |
/// \brief Constructor. |
|
92 |
/// |
|
93 |
/// Constructor. |
|
94 |
/// \param map A map that assigns \c int values to the items. |
|
95 |
/// It is used internally to handle the cross references. |
|
96 |
/// The assigned value must be \c PRE_HEAP (<tt>-1</tt>) for each item. |
|
97 |
explicit BinomHeap(ItemIntMap &map) |
|
98 |
: _min(0), _head(-1), _iim(map), _num_items(0) {} |
|
93 | 99 |
|
94 |
/// \brief |
|
100 |
/// \brief Constructor. |
|
95 | 101 |
/// |
96 |
/// \c _iimap should be given to the constructor, since it is |
|
97 |
/// used internally to handle the cross references. |
|
98 |
explicit BinomHeap(ItemIntMap &_iimap) |
|
99 |
: minimum(0), head(-1), iimap(_iimap), num_items() {} |
|
100 |
|
|
101 |
/// \brief The constructor |
|
102 |
/// |
|
103 |
/// \c _iimap should be given to the constructor, since it is used |
|
104 |
/// internally to handle the cross references. \c _comp is an |
|
105 |
/// object for ordering of the priorities. |
|
106 |
BinomHeap(ItemIntMap &_iimap, const Compare &_comp) |
|
107 |
: minimum(0), head(-1), iimap(_iimap), comp(_comp), num_items() {} |
|
102 |
/// Constructor. |
|
103 |
/// \param map A map that assigns \c int values to the items. |
|
104 |
/// It is used internally to handle the cross references. |
|
105 |
/// The assigned value must be \c PRE_HEAP (<tt>-1</tt>) for each item. |
|
106 |
/// \param comp The function object used for comparing the priorities. |
|
107 |
BinomHeap(ItemIntMap &map, const Compare &comp) |
|
108 |
: _min(0), _head(-1), _iim(map), _comp(comp), _num_items(0) {} |
|
108 | 109 |
|
109 | 110 |
/// \brief The number of items stored in the heap. |
110 | 111 |
/// |
111 |
/// Returns the number of items stored in the heap. |
|
112 |
int size() const { return num_items; } |
|
112 |
/// This function returns the number of items stored in the heap. |
|
113 |
int size() const { return _num_items; } |
|
113 | 114 |
|
114 |
/// \brief |
|
115 |
/// \brief Check if the heap is empty. |
|
115 | 116 |
/// |
116 |
/// Returns \c true if and only if the heap stores no items. |
|
117 |
bool empty() const { return num_items==0; } |
|
117 |
/// This function returns \c true if the heap is empty. |
|
118 |
bool empty() const { return _num_items==0; } |
|
118 | 119 |
|
119 |
/// \brief Make |
|
120 |
/// \brief Make the heap empty. |
|
120 | 121 |
/// |
121 |
/// Make empty this heap. It does not change the cross reference |
|
122 |
/// map. If you want to reuse a heap what is not surely empty you |
|
123 |
/// should first clear the heap and after that you should set the |
|
124 |
/// cross reference map for each item to \c PRE_HEAP. |
|
122 |
/// This functon makes the heap empty. |
|
123 |
/// It does not change the cross reference map. If you want to reuse |
|
124 |
/// a heap that is not surely empty, you should first clear it and |
|
125 |
/// then you should set the cross reference map to \c PRE_HEAP |
|
126 |
/// for each item. |
|
125 | 127 |
void clear() { |
126 |
|
|
128 |
_data.clear(); _min=0; _num_items=0; _head=-1; |
|
127 | 129 |
} |
128 | 130 |
|
129 |
/// \brief \c item gets to the heap with priority \c value independently |
|
130 |
/// if \c item was already there. |
|
131 |
/// \brief Set the priority of an item or insert it, if it is |
|
132 |
/// not stored in the heap. |
|
131 | 133 |
/// |
132 |
/// This method calls \ref push(\c item, \c value) if \c item is not |
|
133 |
/// stored in the heap and it calls \ref decrease(\c item, \c value) or |
|
134 |
/// |
|
134 |
/// This method sets the priority of the given item if it is |
|
135 |
/// already stored in the heap. Otherwise it inserts the given |
|
136 |
/// item into the heap with the given priority. |
|
137 |
/// \param item The item. |
|
138 |
/// \param value The priority. |
|
135 | 139 |
void set (const Item& item, const Prio& value) { |
136 |
int i=iimap[item]; |
|
137 |
if ( i >= 0 && container[i].in ) { |
|
138 |
if ( comp(value, container[i].prio) ) decrease(item, value); |
|
139 |
if ( comp(container[i].prio, value) ) increase(item, value); |
|
140 |
int i=_iim[item]; |
|
141 |
if ( i >= 0 && _data[i].in ) { |
|
142 |
if ( _comp(value, _data[i].prio) ) decrease(item, value); |
|
143 |
if ( _comp(_data[i].prio, value) ) increase(item, value); |
|
140 | 144 |
} else push(item, value); |
141 | 145 |
} |
142 | 146 |
|
143 |
/// \brief |
|
147 |
/// \brief Insert an item into the heap with the given priority. |
|
144 | 148 |
/// |
145 |
/// Adds \c item to the heap with priority \c value. |
|
146 |
/// \pre \c item must not be stored in the heap. |
|
149 |
/// This function inserts the given item into the heap with the |
|
150 |
/// given priority. |
|
151 |
/// \param item The item to insert. |
|
152 |
/// \param value The priority of the item. |
|
153 |
/// \pre \e item must not be stored in the heap. |
|
147 | 154 |
void push (const Item& item, const Prio& value) { |
148 |
int i= |
|
155 |
int i=_iim[item]; |
|
149 | 156 |
if ( i<0 ) { |
150 |
int s=container.size(); |
|
151 |
iimap.set( item,s ); |
|
157 |
int s=_data.size(); |
|
158 |
_iim.set( item,s ); |
|
152 | 159 |
store st; |
153 | 160 |
st.name=item; |
154 |
|
|
161 |
_data.push_back(st); |
|
155 | 162 |
i=s; |
156 | 163 |
} |
157 | 164 |
else { |
158 |
container[i].parent=container[i].right_neighbor=container[i].child=-1; |
|
159 |
container[i].degree=0; |
|
160 |
|
|
165 |
_data[i].parent=_data[i].right_neighbor=_data[i].child=-1; |
|
166 |
_data[i].degree=0; |
|
167 |
_data[i].in=true; |
|
161 | 168 |
} |
162 |
|
|
169 |
_data[i].prio=value; |
|
163 | 170 |
|
164 |
if( 0== |
|
171 |
if( 0==_num_items ) { _head=i; _min=i; } |
|
165 | 172 |
else { merge(i); } |
166 | 173 |
|
167 |
|
|
174 |
_min = findMin(); |
|
168 | 175 |
|
169 |
++ |
|
176 |
++_num_items; |
|
170 | 177 |
} |
171 | 178 |
|
172 |
/// \brief |
|
179 |
/// \brief Return the item having minimum priority. |
|
173 | 180 |
/// |
174 |
/// This method returns the item with minimum priority relative to \c |
|
175 |
/// Compare. |
|
176 |
/// \pre The heap must be nonempty. |
|
177 |
Item top() const { return container[minimum].name; } |
|
181 |
/// This function returns the item having minimum priority. |
|
182 |
/// \pre The heap must be non-empty. |
|
183 |
Item top() const { return _data[_min].name; } |
|
178 | 184 |
|
179 |
/// \brief |
|
185 |
/// \brief The minimum priority. |
|
180 | 186 |
/// |
181 |
/// It returns the minimum priority relative to \c Compare. |
|
182 |
/// \pre The heap must be nonempty. |
|
183 |
|
|
187 |
/// This function returns the minimum priority. |
|
188 |
/// \pre The heap must be non-empty. |
|
189 |
Prio prio() const { return _data[_min].prio; } |
|
184 | 190 |
|
185 |
/// \brief |
|
191 |
/// \brief The priority of the given item. |
|
186 | 192 |
/// |
187 |
/// It returns the priority of \c item. |
|
188 |
/// \pre \c item must be in the heap. |
|
193 |
/// This function returns the priority of the given item. |
|
194 |
/// \param item The item. |
|
195 |
/// \pre \e item must be in the heap. |
|
189 | 196 |
const Prio& operator[](const Item& item) const { |
190 |
return |
|
197 |
return _data[_iim[item]].prio; |
|
191 | 198 |
} |
192 | 199 |
|
193 |
/// \brief |
|
200 |
/// \brief Remove the item having minimum priority. |
|
194 | 201 |
/// |
195 |
/// This method deletes the item with minimum priority relative to \c |
|
196 |
/// Compare from the heap. |
|
202 |
/// This function removes the item having minimum priority. |
|
197 | 203 |
/// \pre The heap must be non-empty. |
198 | 204 |
void pop() { |
199 |
|
|
205 |
_data[_min].in=false; |
|
200 | 206 |
|
201 | 207 |
int head_child=-1; |
202 |
if ( container[minimum].child!=-1 ) { |
|
203 |
int child=container[minimum].child; |
|
208 |
if ( _data[_min].child!=-1 ) { |
|
209 |
int child=_data[_min].child; |
|
204 | 210 |
int neighb; |
205 | 211 |
int prev=-1; |
206 | 212 |
while( child!=-1 ) { |
207 |
neighb=container[child].right_neighbor; |
|
208 |
container[child].parent=-1; |
|
209 |
|
|
213 |
neighb=_data[child].right_neighbor; |
|
214 |
_data[child].parent=-1; |
|
215 |
_data[child].right_neighbor=prev; |
|
210 | 216 |
head_child=child; |
211 | 217 |
prev=child; |
212 | 218 |
child=neighb; |
... | ... |
@@ -214,142 +220,144 @@ |
214 | 220 |
} |
215 | 221 |
|
216 | 222 |
// The first case is that there are only one root. |
217 |
if ( -1==container[head].right_neighbor ) { |
|
218 |
head=head_child; |
|
223 |
if ( -1==_data[_head].right_neighbor ) { |
|
224 |
_head=head_child; |
|
219 | 225 |
} |
220 | 226 |
// The case where there are more roots. |
221 | 227 |
else { |
222 |
if( head!=minimum ) { unlace(minimum); } |
|
223 |
else { head=container[head].right_neighbor; } |
|
228 |
if( _head!=_min ) { unlace(_min); } |
|
229 |
else { _head=_data[_head].right_neighbor; } |
|
224 | 230 |
|
225 | 231 |
merge(head_child); |
226 | 232 |
} |
227 |
minimum=find_min(); |
|
228 |
--num_items; |
|
233 |
_min=findMin(); |
|
234 |
--_num_items; |
|
229 | 235 |
} |
230 | 236 |
|
231 |
/// \brief |
|
237 |
/// \brief Remove the given item from the heap. |
|
232 | 238 |
/// |
233 |
/// This method deletes \c item from the heap, if \c item was already |
|
234 |
/// stored in the heap. It is quite inefficient in Binomial heaps. |
|
239 |
/// This function removes the given item from the heap if it is |
|
240 |
/// already stored. |
|
241 |
/// \param item The item to delete. |
|
242 |
/// \pre \e item must be in the heap. |
|
235 | 243 |
void erase (const Item& item) { |
236 |
int i=iimap[item]; |
|
237 |
if ( i >= 0 && container[i].in ) { |
|
238 |
|
|
244 |
int i=_iim[item]; |
|
245 |
if ( i >= 0 && _data[i].in ) { |
|
246 |
decrease( item, _data[_min].prio-1 ); |
|
239 | 247 |
pop(); |
240 | 248 |
} |
241 | 249 |
} |
242 | 250 |
|
243 |
/// \brief |
|
251 |
/// \brief Decrease the priority of an item to the given value. |
|
244 | 252 |
/// |
245 |
/// This method decreases the priority of \c item to \c value. |
|
246 |
/// \pre \c item must be stored in the heap with priority at least \c |
|
247 |
/// |
|
253 |
/// This function decreases the priority of an item to the given value. |
|
254 |
/// \param item The item. |
|
255 |
/// \param value The priority. |
|
256 |
/// \pre \e item must be stored in the heap with priority at least \e value. |
|
248 | 257 |
void decrease (Item item, const Prio& value) { |
249 |
int i= |
|
258 |
int i=_iim[item]; |
|
250 | 259 |
|
251 |
if( comp( value,container[i].prio ) ) { |
|
252 |
container[i].prio=value; |
|
260 |
if( _comp( value,_data[i].prio ) ) { |
|
261 |
_data[i].prio=value; |
|
253 | 262 |
|
254 |
int p_loc= |
|
263 |
int p_loc=_data[i].parent, loc=i; |
|
255 | 264 |
int parent, child, neighb; |
256 | 265 |
|
257 |
while( -1!=p_loc && |
|
266 |
while( -1!=p_loc && _comp(_data[loc].prio,_data[p_loc].prio) ) { |
|
258 | 267 |
|
259 | 268 |
// parent set for other loc_child |
260 |
child= |
|
269 |
child=_data[loc].child; |
|
261 | 270 |
while( -1!=child ) { |
262 |
container[child].parent=p_loc; |
|
263 |
child=container[child].right_neighbor; |
|
271 |
_data[child].parent=p_loc; |
|
272 |
child=_data[child].right_neighbor; |
|
264 | 273 |
} |
265 | 274 |
|
266 | 275 |
// parent set for other p_loc_child |
267 |
child= |
|
276 |
child=_data[p_loc].child; |
|
268 | 277 |
while( -1!=child ) { |
269 |
container[child].parent=loc; |
|
270 |
child=container[child].right_neighbor; |
|
278 |
_data[child].parent=loc; |
|
279 |
child=_data[child].right_neighbor; |
|
271 | 280 |
} |
272 | 281 |
|
273 |
child=container[p_loc].child; |
|
274 |
container[p_loc].child=container[loc].child; |
|
282 |
child=_data[p_loc].child; |
|
283 |
_data[p_loc].child=_data[loc].child; |
|
275 | 284 |
if( child==loc ) |
276 | 285 |
child=p_loc; |
277 |
|
|
286 |
_data[loc].child=child; |
|
278 | 287 |
|
279 | 288 |
// left_neighb set for p_loc |
280 |
if( container[loc].child!=p_loc ) { |
|
281 |
while( container[child].right_neighbor!=loc ) |
|
282 |
child=container[child].right_neighbor; |
|
283 |
container[child].right_neighbor=p_loc; |
|
289 |
if( _data[loc].child!=p_loc ) { |
|
290 |
while( _data[child].right_neighbor!=loc ) |
|
291 |
child=_data[child].right_neighbor; |
|
292 |
_data[child].right_neighbor=p_loc; |
|
284 | 293 |
} |
285 | 294 |
|
286 | 295 |
// left_neighb set for loc |
287 |
parent=container[p_loc].parent; |
|
288 |
if( -1!=parent ) child=container[parent].child; |
|
289 |
|
|
296 |
parent=_data[p_loc].parent; |
|
297 |
if( -1!=parent ) child=_data[parent].child; |
|
298 |
else child=_head; |
|
290 | 299 |
|
291 | 300 |
if( child!=p_loc ) { |
292 |
while( container[child].right_neighbor!=p_loc ) |
|
293 |
child=container[child].right_neighbor; |
|
294 |
|
|
301 |
while( _data[child].right_neighbor!=p_loc ) |
|
302 |
child=_data[child].right_neighbor; |
|
303 |
_data[child].right_neighbor=loc; |
|
295 | 304 |
} |
296 | 305 |
|
297 |
neighb=container[p_loc].right_neighbor; |
|
298 |
container[p_loc].right_neighbor=container[loc].right_neighbor; |
|
299 |
|
|
306 |
neighb=_data[p_loc].right_neighbor; |
|
307 |
_data[p_loc].right_neighbor=_data[loc].right_neighbor; |
|
308 |
_data[loc].right_neighbor=neighb; |
|
300 | 309 |
|
301 |
container[p_loc].parent=loc; |
|
302 |
container[loc].parent=parent; |
|
310 |
_data[p_loc].parent=loc; |
|
311 |
_data[loc].parent=parent; |
|
303 | 312 |
|
304 |
if( -1!=parent && container[parent].child==p_loc ) |
|
305 |
container[parent].child=loc; |
|
313 |
if( -1!=parent && _data[parent].child==p_loc ) |
|
314 |
_data[parent].child=loc; |
|
306 | 315 |
|
307 | 316 |
/*if new parent will be the first root*/ |
308 |
if( head==p_loc ) |
|
309 |
head=loc; |
|
317 |
if( _head==p_loc ) |
|
318 |
_head=loc; |
|
310 | 319 |
|
311 |
p_loc= |
|
320 |
p_loc=_data[loc].parent; |
|
312 | 321 |
} |
313 | 322 |
} |
314 |
if( comp(value,container[minimum].prio) ) { |
|
315 |
minimum=i; |
|
323 |
if( _comp(value,_data[_min].prio) ) { |
|
324 |
_min=i; |
|
316 | 325 |
} |
317 | 326 |
} |
318 | 327 |
|
319 |
/// \brief |
|
328 |
/// \brief Increase the priority of an item to the given value. |
|
320 | 329 |
/// |
321 |
/// This method sets the priority of \c item to \c value. Though |
|
322 |
/// there is no precondition on the priority of \c item, this |
|
323 |
/// method should be used only if it is indeed necessary to increase |
|
324 |
/// (relative to \c Compare) the priority of \c item, because this |
|
325 |
/// |
|
330 |
/// This function increases the priority of an item to the given value. |
|
331 |
/// \param item The item. |
|
332 |
/// \param value The priority. |
|
333 |
/// \pre \e item must be stored in the heap with priority at most \e value. |
|
326 | 334 |
void increase (Item item, const Prio& value) { |
327 | 335 |
erase(item); |
328 | 336 |
push(item, value); |
329 | 337 |
} |
330 | 338 |
|
331 |
|
|
332 |
/// \brief Returns if \c item is in, has already been in, or has never |
|
333 |
/// |
|
339 |
/// \brief Return the state of an item. |
|
334 | 340 |
/// |
335 |
/// This method returns PRE_HEAP if \c item has never been in the |
|
336 |
/// heap, IN_HEAP if it is in the heap at the moment, and POST_HEAP |
|
337 |
/// otherwise. In the latter case it is possible that \c item will |
|
338 |
/// get back to the heap again. |
|
341 |
/// This method returns \c PRE_HEAP if the given item has never |
|
342 |
/// been in the heap, \c IN_HEAP if it is in the heap at the moment, |
|
343 |
/// and \c POST_HEAP otherwise. |
|
344 |
/// In the latter case it is possible that the item will get back |
|
345 |
/// to the heap again. |
|
346 |
/// \param item The item. |
|
339 | 347 |
State state(const Item &item) const { |
340 |
int i= |
|
348 |
int i=_iim[item]; |
|
341 | 349 |
if( i>=0 ) { |
342 |
if ( |
|
350 |
if ( _data[i].in ) i=0; |
|
343 | 351 |
else i=-2; |
344 | 352 |
} |
345 | 353 |
return State(i); |
346 | 354 |
} |
347 | 355 |
|
348 |
/// \brief |
|
356 |
/// \brief Set the state of an item in the heap. |
|
349 | 357 |
/// |
350 |
/// Sets the state of the \c item in the heap. It can be used to |
|
351 |
/// manually clear the heap when it is important to achive the |
|
352 |
/// |
|
358 |
/// This function sets the state of the given item in the heap. |
|
359 |
/// It can be used to manually clear the heap when it is important |
|
360 |
/// to achive better time complexity. |
|
353 | 361 |
/// \param i The item. |
354 | 362 |
/// \param st The state. It should not be \c IN_HEAP. |
355 | 363 |
void state(const Item& i, State st) { |
... | ... |
@@ -359,7 +367,7 @@ |
359 | 367 |
if (state(i) == IN_HEAP) { |
360 | 368 |
erase(i); |
361 | 369 |
} |
362 |
|
|
370 |
_iim[i] = st; |
|
363 | 371 |
break; |
364 | 372 |
case IN_HEAP: |
365 | 373 |
break; |
... | ... |
@@ -367,20 +375,20 @@ |
367 | 375 |
} |
368 | 376 |
|
369 | 377 |
private: |
370 |
int |
|
378 |
int findMin() { |
|
371 | 379 |
int min_loc=-1, min_val; |
372 |
int x= |
|
380 |
int x=_head; |
|
373 | 381 |
if( x!=-1 ) { |
374 |
min_val= |
|
382 |
min_val=_data[x].prio; |
|
375 | 383 |
min_loc=x; |
376 |
x= |
|
384 |
x=_data[x].right_neighbor; |
|
377 | 385 |
|
378 | 386 |
while( x!=-1 ) { |
379 |
if( comp( container[x].prio,min_val ) ) { |
|
380 |
min_val=container[x].prio; |
|
387 |
if( _comp( _data[x].prio,min_val ) ) { |
|
388 |
min_val=_data[x].prio; |
|
381 | 389 |
min_loc=x; |
382 | 390 |
} |
383 |
x= |
|
391 |
x=_data[x].right_neighbor; |
|
384 | 392 |
} |
385 | 393 |
} |
386 | 394 |
return min_loc; |
... | ... |
@@ -389,29 +397,29 @@ |
389 | 397 |
void merge(int a) { |
390 | 398 |
interleave(a); |
391 | 399 |
|
392 |
int x= |
|
400 |
int x=_head; |
|
393 | 401 |
if( -1!=x ) { |
394 |
int x_prev=-1, x_next= |
|
402 |
int x_prev=-1, x_next=_data[x].right_neighbor; |
|
395 | 403 |
while( -1!=x_next ) { |
396 |
if( |
|
404 |
if( _data[x].degree!=_data[x_next].degree || ( -1!=_data[x_next].right_neighbor && _data[_data[x_next].right_neighbor].degree==_data[x].degree ) ) { |
|
397 | 405 |
x_prev=x; |
398 | 406 |
x=x_next; |
399 | 407 |
} |
400 | 408 |
else { |
401 |
if( comp(container[x].prio,container[x_next].prio) ) { |
|
402 |
container[x].right_neighbor=container[x_next].right_neighbor; |
|
409 |
if( _comp(_data[x].prio,_data[x_next].prio) ) { |
|
410 |
_data[x].right_neighbor=_data[x_next].right_neighbor; |
|
403 | 411 |
fuse(x_next,x); |
404 | 412 |
} |
405 | 413 |
else { |
406 |
if( -1==x_prev ) { |
|
414 |
if( -1==x_prev ) { _head=x_next; } |
|
407 | 415 |
else { |
408 |
|
|
416 |
_data[x_prev].right_neighbor=x_next; |
|
409 | 417 |
} |
410 | 418 |
fuse(x,x_next); |
411 | 419 |
x=x_next; |
412 | 420 |
} |
413 | 421 |
} |
414 |
x_next= |
|
422 |
x_next=_data[x].right_neighbor; |
|
415 | 423 |
} |
416 | 424 |
} |
417 | 425 |
} |
... | ... |
@@ -419,68 +427,68 @@ |
419 | 427 |
void interleave(int a) { |
420 | 428 |
int other=-1, head_other=-1; |
421 | 429 |
|
422 |
while( -1!=a || -1!= |
|
430 |
while( -1!=a || -1!=_head ) { |
|
423 | 431 |
if( -1==a ) { |
424 | 432 |
if( -1==head_other ) { |
425 |
head_other= |
|
433 |
head_other=_head; |
|
426 | 434 |
} |
427 | 435 |
else { |
428 |
|
|
436 |
_data[other].right_neighbor=_head; |
|
429 | 437 |
} |
430 |
|
|
438 |
_head=-1; |
|
431 | 439 |
} |
432 |
else if( -1== |
|
440 |
else if( -1==_head ) { |
|
433 | 441 |
if( -1==head_other ) { |
434 | 442 |
head_other=a; |
435 | 443 |
} |
436 | 444 |
else { |
437 |
|
|
445 |
_data[other].right_neighbor=a; |
|
438 | 446 |
} |
439 | 447 |
a=-1; |
440 | 448 |
} |
441 | 449 |
else { |
442 |
if( |
|
450 |
if( _data[a].degree<_data[_head].degree ) { |
|
443 | 451 |
if( -1==head_other ) { |
444 | 452 |
head_other=a; |
445 | 453 |
} |
446 | 454 |
else { |
447 |
|
|
455 |
_data[other].right_neighbor=a; |
|
448 | 456 |
} |
449 | 457 |
other=a; |
450 |
a= |
|
458 |
a=_data[a].right_neighbor; |
|
451 | 459 |
} |
452 | 460 |
else { |
453 | 461 |
if( -1==head_other ) { |
454 |
head_other= |
|
462 |
head_other=_head; |
|
455 | 463 |
} |
456 | 464 |
else { |
457 |
|
|
465 |
_data[other].right_neighbor=_head; |
|
458 | 466 |
} |
459 |
other=head; |
|
460 |
head=container[head].right_neighbor; |
|
467 |
other=_head; |
|
468 |
_head=_data[_head].right_neighbor; |
|
461 | 469 |
} |
462 | 470 |
} |
463 | 471 |
} |
464 |
|
|
472 |
_head=head_other; |
|
465 | 473 |
} |
466 | 474 |
|
467 | 475 |
// Lacing a under b |
468 | 476 |
void fuse(int a, int b) { |
469 |
container[a].parent=b; |
|
470 |
container[a].right_neighbor=container[b].child; |
|
471 |
|
|
477 |
_data[a].parent=b; |
|
478 |
_data[a].right_neighbor=_data[b].child; |
|
479 |
_data[b].child=a; |
|
472 | 480 |
|
473 |
++ |
|
481 |
++_data[b].degree; |
|
474 | 482 |
} |
475 | 483 |
|
476 | 484 |
// It is invoked only if a has siblings. |
477 | 485 |
void unlace(int a) { |
478 |
int neighb=container[a].right_neighbor; |
|
479 |
int other=head; |
|
486 |
int neighb=_data[a].right_neighbor; |
|
487 |
int other=_head; |
|
480 | 488 |
|
481 |
while( container[other].right_neighbor!=a ) |
|
482 |
other=container[other].right_neighbor; |
|
483 |
|
|
489 |
while( _data[other].right_neighbor!=a ) |
|
490 |
other=_data[other].right_neighbor; |
|
491 |
_data[other].right_neighbor=neighb; |
|
484 | 492 |
} |
485 | 493 |
|
486 | 494 |
private: |
1 |
/* -*- C++ -*- |
|
1 |
/* -*- mode: C++; indent-tabs-mode: nil; -*- |
|
2 | 2 |
* |
3 |
* This file is a part of LEMON, a generic C++ optimization library |
|
3 |
* This file is a part of LEMON, a generic C++ optimization library. |
|
4 | 4 |
* |
5 |
* Copyright (C) 2003- |
|
5 |
* Copyright (C) 2003-2009 |
|
6 | 6 |
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
7 | 7 |
* (Egervary Research Group on Combinatorial Optimization, EGRES). |
8 | 8 |
* |
... | ... |
@@ -19,159 +19,158 @@ |
19 | 19 |
#ifndef LEMON_FOURARY_HEAP_H |
20 | 20 |
#define LEMON_FOURARY_HEAP_H |
21 | 21 |
|
22 |
///\ingroup |
|
22 |
///\ingroup heaps |
|
23 | 23 |
///\file |
24 |
///\brief |
|
24 |
///\brief Fourary heap implementation. |
|
25 | 25 |
|
26 |
#include <iostream> |
|
27 | 26 |
#include <vector> |
28 | 27 |
#include <utility> |
29 | 28 |
#include <functional> |
30 | 29 |
|
31 | 30 |
namespace lemon { |
32 | 31 |
|
33 |
///\ingroup |
|
32 |
/// \ingroup heaps |
|
34 | 33 |
/// |
35 |
///\brief |
|
34 |
///\brief Fourary heap data structure. |
|
36 | 35 |
/// |
37 |
///This class implements the \e 4ary \e heap data structure. A \e heap |
|
38 |
///is a data structure for storing items with specified values called \e |
|
39 |
///priorities in such a way that finding the item with minimum priority is |
|
40 |
///efficient. \c Compare specifies the ordering of the priorities. In a heap |
|
41 |
/// |
|
36 |
/// This class implements the \e fourary \e heap data structure. |
|
37 |
/// It fully conforms to the \ref concepts::Heap "heap concept". |
|
42 | 38 |
/// |
43 |
///\param _Prio Type of the priority of the items. |
|
44 |
///\param _ItemIntMap A read and writable Item int map, used internally |
|
45 |
///to handle the cross references. |
|
46 |
///\param _Compare A class for the ordering of the priorities. The |
|
47 |
/// |
|
39 |
/// The fourary heap is a specialization of the \ref KaryHeap "K-ary heap" |
|
40 |
/// for <tt>K=4</tt>. It is similar to the \ref BinHeap "binary heap", |
|
41 |
/// but its nodes have at most four children, instead of two. |
|
48 | 42 |
/// |
49 |
///\sa FibHeap |
|
50 |
///\sa Dijkstra |
|
51 |
///\ |
|
43 |
/// \tparam PR Type of the priorities of the items. |
|
44 |
/// \tparam IM A read-writable item map with \c int values, used |
|
45 |
/// internally to handle the cross references. |
|
46 |
/// \tparam CMP A functor class for comparing the priorities. |
|
47 |
/// The default is \c std::less<PR>. |
|
48 |
/// |
|
49 |
///\sa BinHeap |
|
50 |
///\sa KaryHeap |
|
51 |
#ifdef DOXYGEN |
|
52 |
template <typename PR, typename IM, typename CMP> |
|
53 |
#else |
|
54 |
template <typename PR, typename IM, typename CMP = std::less<PR> > |
|
55 |
#endif |
|
56 |
class FouraryHeap { |
|
57 |
public: |
|
58 |
/// Type of the item-int map. |
|
59 |
typedef IM ItemIntMap; |
|
60 |
/// Type of the priorities. |
|
61 |
typedef PR Prio; |
|
62 |
/// Type of the items stored in the heap. |
|
63 |
typedef typename ItemIntMap::Key Item; |
|
64 |
/// Type of the item-priority pairs. |
|
65 |
typedef std::pair<Item,Prio> Pair; |
|
66 |
/// Functor type for comparing the priorities. |
|
67 |
typedef CMP Compare; |
|
52 | 68 |
|
53 |
template <typename _Prio, typename _ItemIntMap, |
|
54 |
typename _Compare = std::less<_Prio> > |
|
55 |
|
|
56 |
class FouraryHeap { |
|
57 |
|
|
58 |
public: |
|
59 |
///\e |
|
60 |
typedef _ItemIntMap ItemIntMap; |
|
61 |
///\e |
|
62 |
typedef _Prio Prio; |
|
63 |
///\e |
|
64 |
typedef typename ItemIntMap::Key Item; |
|
65 |
///\e |
|
66 |
typedef std::pair<Item,Prio> Pair; |
|
67 |
///\e |
|
68 |
typedef _Compare Compare; |
|
69 |
|
|
70 |
/// \brief Type to represent the items states. |
|
69 |
/// \brief Type to represent the states of the items. |
|
71 | 70 |
/// |
72 |
/// Each Item element have a state associated to it. It may be "in heap", |
|
73 |
/// "pre heap" or "post heap". The latter two are indifferent from the |
|
71 |
/// Each item has a state associated to it. It can be "in heap", |
|
72 |
/// "pre-heap" or "post-heap". The latter two are indifferent from the |
|
74 | 73 |
/// heap's point of view, but may be useful to the user. |
75 | 74 |
/// |
76 |
/// The ItemIntMap \e should be initialized in such way that it maps |
|
77 |
/// PRE_HEAP (-1) to any element to be put in the heap... |
|
75 |
/// The item-int map must be initialized in such way that it assigns |
|
76 |
/// \c PRE_HEAP (<tt>-1</tt>) to any element to be put in the heap. |
|
78 | 77 |
enum State { |
79 |
IN_HEAP = 0, |
|
80 |
PRE_HEAP = -1, |
|
81 |
|
|
78 |
IN_HEAP = 0, ///< = 0. |
|
79 |
PRE_HEAP = -1, ///< = -1. |
|
80 |
POST_HEAP = -2 ///< = -2. |
|
82 | 81 |
}; |
83 | 82 |
|
84 | 83 |
private: |
85 |
std::vector<Pair> data; |
|
86 |
Compare comp; |
|
87 |
|
|
84 |
std::vector<Pair> _data; |
|
85 |
Compare _comp; |
|
86 |
ItemIntMap &_iim; |
|
88 | 87 |
|
89 | 88 |
public: |
90 |
/// \brief |
|
89 |
/// \brief Constructor. |
|
91 | 90 |
/// |
92 |
/// The constructor. |
|
93 |
/// \param _iim should be given to the constructor, since it is used |
|
94 |
/// internally to handle the cross references. The value of the map |
|
95 |
/// should be PRE_HEAP (-1) for each element. |
|
96 |
|
|
91 |
/// Constructor. |
|
92 |
/// \param map A map that assigns \c int values to the items. |
|
93 |
/// It is used internally to handle the cross references. |
|
94 |
/// The assigned value must be \c PRE_HEAP (<tt>-1</tt>) for each item. |
|
95 |
explicit FouraryHeap(ItemIntMap &map) : _iim(map) {} |
|
97 | 96 |
|
98 |
/// \brief |
|
97 |
/// \brief Constructor. |
|
99 | 98 |
/// |
100 |
/// The constructor. |
|
101 |
/// \param _iim should be given to the constructor, since it is used |
|
102 |
/// internally to handle the cross references. The value of the map |
|
103 |
/// should be PRE_HEAP (-1) for each element. |
|
99 |
/// Constructor. |
|
100 |
/// \param map A map that assigns \c int values to the items. |
|
101 |
/// It is used internally to handle the cross references. |
|
102 |
/// The assigned value must be \c PRE_HEAP (<tt>-1</tt>) for each item. |
|
103 |
/// \param comp The function object used for comparing the priorities. |
|
104 |
FouraryHeap(ItemIntMap &map, const Compare &comp) |
|
105 |
: _iim(map), _comp(comp) {} |
|
106 |
|
|
107 |
/// \brief The number of items stored in the heap. |
|
104 | 108 |
/// |
105 |
/// \param _comp The comparator function object. |
|
106 |
FouraryHeap(ItemIntMap &_iim, const Compare &_comp) |
|
107 |
|
|
109 |
/// This function returns the number of items stored in the heap. |
|
110 |
int size() const { return _data.size(); } |
|
108 | 111 |
|
109 |
/// |
|
112 |
/// \brief Check if the heap is empty. |
|
110 | 113 |
/// |
111 |
/// \brief Returns the number of items stored in the heap. |
|
112 |
int size() const { return data.size(); } |
|
114 |
/// This function returns \c true if the heap is empty. |
|
115 |
bool empty() const { return _data.empty(); } |
|
113 | 116 |
|
114 |
/// \brief |
|
117 |
/// \brief Make the heap empty. |
|
115 | 118 |
/// |
116 |
/// Returns \c true if and only if the heap stores no items. |
|
117 |
bool empty() const { return data.empty(); } |
|
118 |
|
|
119 |
/// \brief Make empty this heap. |
|
120 |
/// |
|
121 |
/// Make empty this heap. It does not change the cross reference map. |
|
122 |
/// If you want to reuse what is not surely empty you should first clear |
|
123 |
/// the heap and after that you should set the cross reference map for |
|
124 |
/// each item to \c PRE_HEAP. |
|
125 |
void clear() { data.clear(); } |
|
119 |
/// This functon makes the heap empty. |
|
120 |
/// It does not change the cross reference map. If you want to reuse |
|
121 |
/// a heap that is not surely empty, you should first clear it and |
|
122 |
/// then you should set the cross reference map to \c PRE_HEAP |
|
123 |
/// for each item. |
|
124 |
void clear() { _data.clear(); } |
|
126 | 125 |
|
127 | 126 |
private: |
128 | 127 |
static int parent(int i) { return (i-1)/4; } |
129 | 128 |
static int firstChild(int i) { return 4*i+1; } |
130 | 129 |
|
131 | 130 |
bool less(const Pair &p1, const Pair &p2) const { |
132 |
return |
|
131 |
return _comp(p1.second, p2.second); |
|
133 | 132 |
} |
134 | 133 |
|
135 |
int |
|
134 |
int findMin(const int child, const int length) { |
|
136 | 135 |
int min=child; |
137 | 136 |
if( child+3<length ) { |
138 |
if( less( |
|
137 |
if( less(_data[child+3], _data[min]) ) |
|
139 | 138 |
min=child+3; |
140 |
if( less( |
|
139 |
if( less(_data[child+2], _data[min]) ) |
|
141 | 140 |
min=child+2; |
142 |
if( less( |
|
141 |
if( less(_data[child+1], _data[min]) ) |
|
143 | 142 |
min=child+1; |
144 | 143 |
} |
145 | 144 |
else if( child+2<length ) { |
146 |
if( less( |
|
145 |
if( less(_data[child+2], _data[min]) ) |
|
147 | 146 |
min=child+2; |
148 |
if( less( |
|
147 |
if( less(_data[child+1], _data[min]) ) |
|
149 | 148 |
min=child+1; |
150 | 149 |
} |
151 | 150 |
else if( child+1<length ) { |
152 |
if( less( |
|
151 |
if( less(_data[child+1], _data[min]) ) |
|
153 | 152 |
min=child+1; |
154 | 153 |
} |
155 | 154 |
return min; |
156 | 155 |
} |
157 | 156 |
|
158 |
void |
|
157 |
void bubbleUp(int hole, Pair p) { |
|
159 | 158 |
int par = parent(hole); |
160 |
while( hole>0 && less(p,data[par]) ) { |
|
161 |
move(data[par],hole); |
|
159 |
while( hole>0 && less(p,_data[par]) ) { |
|
160 |
move(_data[par],hole); |
|
162 | 161 |
hole = par; |
163 | 162 |
par = parent(hole); |
164 | 163 |
} |
165 | 164 |
move(p, hole); |
166 | 165 |
} |
167 | 166 |
|
168 |
void |
|
167 |
void bubbleDown(int hole, Pair p, int length) { |
|
169 | 168 |
int child = firstChild(hole); |
170 | 169 |
while( child<length && length>1 ) { |
171 |
child = find_min(child,length); |
|
172 |
if( !less(data[child], p) ) |
|
170 |
child = findMin(child,length); |
|
171 |
if( !less(_data[child], p) ) |
|
173 | 172 |
goto ok; |
174 |
move( |
|
173 |
move(_data[child], hole); |
|
175 | 174 |
hole = child; |
176 | 175 |
child = firstChild(hole); |
177 | 176 |
} |
... | ... |
@@ -180,142 +179,143 @@ |
180 | 179 |
} |
181 | 180 |
|
182 | 181 |
void move(const Pair &p, int i) { |
183 |
data[i] = p; |
|
184 |
iim.set(p.first, i); |
|
182 |
_data[i] = p; |
|
183 |
_iim.set(p.first, i); |
|
185 | 184 |
} |
186 | 185 |
|
187 | 186 |
public: |
188 |
|
|
189 | 187 |
/// \brief Insert a pair of item and priority into the heap. |
190 | 188 |
/// |
191 |
/// |
|
189 |
/// This function inserts \c p.first to the heap with priority |
|
190 |
/// \c p.second. |
|
192 | 191 |
/// \param p The pair to insert. |
192 |
/// \pre \c p.first must not be stored in the heap. |
|
193 | 193 |
void push(const Pair &p) { |
194 |
int n = data.size(); |
|
195 |
data.resize(n+1); |
|
196 |
|
|
194 |
int n = _data.size(); |
|
195 |
_data.resize(n+1); |
|
196 |
bubbleUp(n, p); |
|
197 | 197 |
} |
198 | 198 |
|
199 |
/// \brief Insert an item into the heap with the given |
|
199 |
/// \brief Insert an item into the heap with the given priority. |
|
200 | 200 |
/// |
201 |
/// |
|
201 |
/// This function inserts the given item into the heap with the |
|
202 |
/// given priority. |
|
202 | 203 |
/// \param i The item to insert. |
203 | 204 |
/// \param p The priority of the item. |
205 |
/// \pre \e i must not be stored in the heap. |
|
204 | 206 |
void push(const Item &i, const Prio &p) { push(Pair(i,p)); } |
205 | 207 |
|
206 |
/// \brief |
|
208 |
/// \brief Return the item having minimum priority. |
|
207 | 209 |
/// |
208 |
/// This method returns the item with minimum priority relative to \c |
|
209 |
/// Compare. |
|
210 |
/// \pre The heap must be nonempty. |
|
211 |
Item top() const { return data[0].first; } |
|
210 |
/// This function returns the item having minimum priority. |
|
211 |
/// \pre The heap must be non-empty. |
|
212 |
Item top() const { return _data[0].first; } |
|
212 | 213 |
|
213 |
/// \brief |
|
214 |
/// \brief The minimum priority. |
|
214 | 215 |
/// |
215 |
/// It returns the minimum priority relative to \c Compare. |
|
216 |
/// \pre The heap must be nonempty. |
|
217 |
|
|
216 |
/// This function returns the minimum priority. |
|
217 |
/// \pre The heap must be non-empty. |
|
218 |
Prio prio() const { return _data[0].second; } |
|
218 | 219 |
|
219 |
/// \brief |
|
220 |
/// \brief Remove the item having minimum priority. |
|
220 | 221 |
/// |
221 |
/// This method deletes the item with minimum priority relative to \c |
|
222 |
/// Compare from the heap. |
|
222 |
/// This function removes the item having minimum priority. |
|
223 | 223 |
/// \pre The heap must be non-empty. |
224 | 224 |
void pop() { |
225 |
int n = data.size()-1; |
|
226 |
iim.set(data[0].first, POST_HEAP); |
|
227 |
if (n>0) bubble_down(0, data[n], n); |
|
228 |
data.pop_back(); |
|
225 |
int n = _data.size()-1; |
|
226 |
_iim.set(_data[0].first, POST_HEAP); |
|
227 |
if (n>0) bubbleDown(0, _data[n], n); |
|
228 |
_data.pop_back(); |
|
229 | 229 |
} |
230 | 230 |
|
231 |
/// \brief |
|
231 |
/// \brief Remove the given item from the heap. |
|
232 | 232 |
/// |
233 |
/// This method deletes item \c i from the heap. |
|
234 |
/// \param i The item to erase. |
|
235 |
/// |
|
233 |
/// This function removes the given item from the heap if it is |
|
234 |
/// already stored. |
|
235 |
/// \param i The item to delete. |
|
236 |
/// \pre \e i must be in the heap. |
|
236 | 237 |
void erase(const Item &i) { |
237 |
int h = iim[i]; |
|
238 |
int n = data.size()-1; |
|
239 |
|
|
238 |
int h = _iim[i]; |
|
239 |
int n = _data.size()-1; |
|
240 |
_iim.set(_data[h].first, POST_HEAP); |
|
240 | 241 |
if( h<n ) { |
241 |
if( less(data[parent(h)], data[n]) ) |
|
242 |
bubble_down(h, data[n], n); |
|
242 |
if( less(_data[parent(h)], _data[n]) ) |
|
243 |
bubbleDown(h, _data[n], n); |
|
243 | 244 |
else |
244 |
|
|
245 |
bubbleUp(h, _data[n]); |
|
245 | 246 |
} |
246 |
|
|
247 |
_data.pop_back(); |
|
247 | 248 |
} |
248 | 249 |
|
249 |
/// \brief |
|
250 |
/// \brief The priority of the given item. |
|
250 | 251 |
/// |
251 |
/// This function returns the priority of item \c i. |
|
252 |
/// \pre \c i must be in the heap. |
|
252 |
/// This function returns the priority of the given item. |
|
253 | 253 |
/// \param i The item. |
254 |
/// \pre \e i must be in the heap. |
|
254 | 255 |
Prio operator[](const Item &i) const { |
255 |
int idx = iim[i]; |
|
256 |
return data[idx].second; |
|
256 |
int idx = _iim[i]; |
|
257 |
return _data[idx].second; |
|
257 | 258 |
} |
258 | 259 |
|
259 |
/// \brief \c i gets to the heap with priority \c p independently |
|
260 |
/// if \c i was already there. |
|
260 |
/// \brief Set the priority of an item or insert it, if it is |
|
261 |
/// not stored in the heap. |
|
261 | 262 |
/// |
262 |
/// This method calls \ref push(\c i, \c p) if \c i is not stored |
|
263 |
/// in the heap and sets the priority of \c i to \c p otherwise. |
|
263 |
/// This method sets the priority of the given item if it is |
|
264 |
/// already stored in the heap. Otherwise it inserts the given |
|
265 |
/// item into the heap with the given priority. |
|
264 | 266 |
/// \param i The item. |
265 | 267 |
/// \param p The priority. |
266 | 268 |
void set(const Item &i, const Prio &p) { |
267 |
int idx = |
|
269 |
int idx = _iim[i]; |
|
268 | 270 |
if( idx < 0 ) |
269 | 271 |
push(i,p); |
270 |
else if( comp(p, data[idx].second) ) |
|
271 |
bubble_up(idx, Pair(i,p)); |
|
272 |
else if( _comp(p, _data[idx].second) ) |
|
273 |
bubbleUp(idx, Pair(i,p)); |
|
272 | 274 |
else |
273 |
|
|
275 |
bubbleDown(idx, Pair(i,p), _data.size()); |
|
274 | 276 |
} |
275 | 277 |
|
276 |
/// \brief |
|
278 |
/// \brief Decrease the priority of an item to the given value. |
|
277 | 279 |
/// |
278 |
/// This method decreases the priority of item \c i to \c p. |
|
279 |
/// \pre \c i must be stored in the heap with priority at least \c |
|
280 |
/// |
|
280 |
/// This function decreases the priority of an item to the given value. |
|
281 | 281 |
/// \param i The item. |
282 | 282 |
/// \param p The priority. |
283 |
/// \pre \e i must be stored in the heap with priority at least \e p. |
|
283 | 284 |
void decrease(const Item &i, const Prio &p) { |
284 |
int idx = iim[i]; |
|
285 |
bubble_up(idx, Pair(i,p)); |
|
285 |
int idx = _iim[i]; |
|
286 |
bubbleUp(idx, Pair(i,p)); |
|
286 | 287 |
} |
287 | 288 |
|
288 |
/// \brief |
|
289 |
/// \brief Increase the priority of an item to the given value. |
|
289 | 290 |
/// |
290 |
/// This method sets the priority of item \c i to \c p. |
|
291 |
/// \pre \c i must be stored in the heap with priority at most \c |
|
292 |
/// |
|
291 |
/// This function increases the priority of an item to the given value. |
|
293 | 292 |
/// \param i The item. |
294 | 293 |
/// \param p The priority. |
294 |
/// \pre \e i must be stored in the heap with priority at most \e p. |
|
295 | 295 |
void increase(const Item &i, const Prio &p) { |
296 |
int idx = iim[i]; |
|
297 |
bubble_down(idx, Pair(i,p), data.size()); |
|
296 |
int idx = _iim[i]; |
|
297 |
bubbleDown(idx, Pair(i,p), _data.size()); |
|
298 | 298 |
} |
299 | 299 |
|
300 |
/// \brief Returns if \c item is in, has already been in, or has |
|
301 |
/// never been in the heap. |
|
300 |
/// \brief Return the state of an item. |
|
302 | 301 |
/// |
303 |
/// This method returns PRE_HEAP if \c item has never been in the |
|
304 |
/// heap, IN_HEAP if it is in the heap at the moment, and POST_HEAP |
|
305 |
/// otherwise. In the latter case it is possible that \c item will |
|
306 |
/// get back to the heap again. |
|
302 |
/// This method returns \c PRE_HEAP if the given item has never |
|
303 |
/// been in the heap, \c IN_HEAP if it is in the heap at the moment, |
|
304 |
/// and \c POST_HEAP otherwise. |
|
305 |
/// In the latter case it is possible that the item will get back |
|
306 |
/// to the heap again. |
|
307 | 307 |
/// \param i The item. |
308 | 308 |
State state(const Item &i) const { |
309 |
int s = |
|
309 |
int s = _iim[i]; |
|
310 | 310 |
if (s>=0) s=0; |
311 | 311 |
return State(s); |
312 | 312 |
} |
313 | 313 |
|
314 |
/// \brief |
|
314 |
/// \brief Set the state of an item in the heap. |
|
315 | 315 |
/// |
316 |
/// Sets the state of the \c item in the heap. It can be used to |
|
317 |
/// manually clear the heap when it is important to achive the |
|
318 |
/// |
|
316 |
/// This function sets the state of the given item in the heap. |
|
317 |
/// It can be used to manually clear the heap when it is important |
|
318 |
/// to achive better time complexity. |
|
319 | 319 |
/// \param i The item. |
320 | 320 |
/// \param st The state. It should not be \c IN_HEAP. |
321 | 321 |
void state(const Item& i, State st) { |
... | ... |
@@ -323,24 +323,25 @@ |
323 | 323 |
case POST_HEAP: |
324 | 324 |
case PRE_HEAP: |
325 | 325 |
if (state(i) == IN_HEAP) erase(i); |
326 |
|
|
326 |
_iim[i] = st; |
|
327 | 327 |
break; |
328 | 328 |
case IN_HEAP: |
329 | 329 |
break; |
330 | 330 |
} |
331 | 331 |
} |
332 | 332 |
|
333 |
/// \brief |
|
333 |
/// \brief Replace an item in the heap. |
|
334 | 334 |
/// |
335 |
/// The \c i item is replaced with \c j item. The \c i item should |
|
336 |
/// be in the heap, while the \c j should be out of the heap. The |
|
337 |
/// \c i item will out of the heap and \c j will be in the heap |
|
338 |
/// with the same prioriority as prevoiusly the \c i item. |
|
335 |
/// This function replaces item \c i with item \c j. |
|
336 |
/// Item \c i must be in the heap, while \c j must be out of the heap. |
|
337 |
/// After calling this method, item \c i will be out of the |
|
338 |
/// heap and \c j will be in the heap with the same prioriority |
|
339 |
/// as item \c i had before. |
|
339 | 340 |
void replace(const Item& i, const Item& j) { |
340 |
int idx = iim[i]; |
|
341 |
iim.set(i, iim[j]); |
|
342 |
iim.set(j, idx); |
|
343 |
data[idx].first = j; |
|
341 |
int idx = _iim[i]; |
|
342 |
_iim.set(i, _iim[j]); |
|
343 |
_iim.set(j, idx); |
|
344 |
_data[idx].first = j; |
|
344 | 345 |
} |
345 | 346 |
|
346 | 347 |
}; // class FouraryHeap |
1 |
/* -*- C++ -*- |
|
1 |
/* -*- mode: C++; indent-tabs-mode: nil; -*- |
|
2 | 2 |
* |
3 |
* This file is a part of LEMON, a generic C++ optimization library |
|
3 |
* This file is a part of LEMON, a generic C++ optimization library. |
|
4 | 4 |
* |
5 |
* Copyright (C) 2003- |
|
5 |
* Copyright (C) 2003-2009 |
|
6 | 6 |
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
7 | 7 |
* (Egervary Research Group on Combinatorial Optimization, EGRES). |
8 | 8 |
* |
... | ... |
@@ -19,152 +19,151 @@ |
19 | 19 |
#ifndef LEMON_KARY_HEAP_H |
20 | 20 |
#define LEMON_KARY_HEAP_H |
21 | 21 |
|
22 |
///\ingroup |
|
22 |
///\ingroup heaps |
|
23 | 23 |
///\file |
24 |
///\brief |
|
24 |
///\brief Fourary heap implementation. |
|
25 | 25 |
|
26 |
#include <iostream> |
|
27 | 26 |
#include <vector> |
28 | 27 |
#include <utility> |
29 | 28 |
#include <functional> |
30 | 29 |
|
31 | 30 |
namespace lemon { |
32 | 31 |
|
33 |
///\ingroup |
|
32 |
/// \ingroup heaps |
|
34 | 33 |
/// |
35 |
///\brief |
|
34 |
///\brief K-ary heap data structure. |
|
36 | 35 |
/// |
37 |
///This class implements the \e Kary \e heap data structure. A \e heap |
|
38 |
///is a data structure for storing items with specified values called \e |
|
39 |
///priorities in such a way that finding the item with minimum priority is |
|
40 |
///efficient. \c Compare specifies the ordering of the priorities. In a heap |
|
41 |
/// |
|
36 |
/// This class implements the \e K-ary \e heap data structure. |
|
37 |
/// It fully conforms to the \ref concepts::Heap "heap concept". |
|
42 | 38 |
/// |
43 |
///\param _Prio Type of the priority of the items. |
|
44 |
///\param _ItemIntMap A read and writable Item int map, used internally |
|
45 |
///to handle the cross references. |
|
46 |
///\param _Compare A class for the ordering of the priorities. The |
|
47 |
/// |
|
39 |
/// The \ref KaryHeap "K-ary heap" is a generalization of the |
|
40 |
/// \ref BinHeap "binary heap" structure, its nodes have at most |
|
41 |
/// \c K children, instead of two. |
|
42 |
/// \ref BinHeap and \ref FouraryHeap are specialized implementations |
|
43 |
/// of this structure for <tt>K=2</tt> and <tt>K=4</tt>, respectively. |
|
48 | 44 |
/// |
49 |
///\sa FibHeap |
|
50 |
///\sa Dijkstra |
|
51 |
///\ |
|
45 |
/// \tparam PR Type of the priorities of the items. |
|
46 |
/// \tparam IM A read-writable item map with \c int values, used |
|
47 |
/// internally to handle the cross references. |
|
48 |
/// \tparam CMP A functor class for comparing the priorities. |
|
49 |
/// The default is \c std::less<PR>. |
|
50 |
/// |
|
51 |
///\sa BinHeap |
|
52 |
///\sa FouraryHeap |
|
53 |
#ifdef DOXYGEN |
|
54 |
template <typename PR, typename IM, typename CMP> |
|
55 |
#else |
|
56 |
template <typename PR, typename IM, typename CMP = std::less<PR> > |
|
57 |
#endif |
|
58 |
class KaryHeap { |
|
59 |
public: |
|
60 |
/// Type of the item-int map. |
|
61 |
typedef IM ItemIntMap; |
|
62 |
/// Type of the priorities. |
|
63 |
typedef PR Prio; |
|
64 |
/// Type of the items stored in the heap. |
|
65 |
typedef typename ItemIntMap::Key Item; |
|
66 |
/// Type of the item-priority pairs. |
|
67 |
typedef std::pair<Item,Prio> Pair; |
|
68 |
/// Functor type for comparing the priorities. |
|
69 |
typedef CMP Compare; |
|
52 | 70 |
|
53 |
template <typename _Prio, typename _ItemIntMap, |
|
54 |
typename _Compare = std::less<_Prio> > |
|
55 |
|
|
56 |
class KaryHeap { |
|
57 |
|
|
58 |
public: |
|
59 |
///\e |
|
60 |
typedef _ItemIntMap ItemIntMap; |
|
61 |
///\e |
|
62 |
typedef _Prio Prio; |
|
63 |
///\e |
|
64 |
typedef typename ItemIntMap::Key Item; |
|
65 |
///\e |
|
66 |
typedef std::pair<Item,Prio> Pair; |
|
67 |
///\e |
|
68 |
typedef _Compare Compare; |
|
69 |
///\e |
|
70 |
|
|
71 |
/// \brief Type to represent the |
|
71 |
/// \brief Type to represent the states of the items. |
|
72 | 72 |
/// |
73 |
/// Each Item element have a state associated to it. It may be "in heap", |
|
74 |
/// "pre heap" or "post heap". The latter two are indifferent from the |
|
73 |
/// Each item has a state associated to it. It can be "in heap", |
|
74 |
/// "pre-heap" or "post-heap". The latter two are indifferent from the |
|
75 | 75 |
/// heap's point of view, but may be useful to the user. |
76 | 76 |
/// |
77 |
/// The ItemIntMap \e should be initialized in such way that it maps |
|
78 |
/// PRE_HEAP (-1) to any element to be put in the heap... |
|
77 |
/// The item-int map must be initialized in such way that it assigns |
|
78 |
/// \c PRE_HEAP (<tt>-1</tt>) to any element to be put in the heap. |
|
79 | 79 |
enum State { |
80 |
IN_HEAP = 0, |
|
81 |
PRE_HEAP = -1, |
|
82 |
|
|
80 |
IN_HEAP = 0, ///< = 0. |
|
81 |
PRE_HEAP = -1, ///< = -1. |
|
82 |
POST_HEAP = -2 ///< = -2. |
|
83 | 83 |
}; |
84 | 84 |
|
85 | 85 |
private: |
86 |
std::vector<Pair> data; |
|
87 |
Compare comp; |
|
88 |
ItemIntMap &iim; |
|
89 |
int K; |
|
86 |
std::vector<Pair> _data; |
|
87 |
Compare _comp; |
|
88 |
ItemIntMap &_iim; |
|
89 |
int _K; |
|
90 | 90 |
|
91 | 91 |
public: |
92 |
/// \brief |
|
92 |
/// \brief Constructor. |
|
93 | 93 |
/// |
94 |
/// The constructor. |
|
95 |
/// \param _iim should be given to the constructor, since it is used |
|
96 |
/// internally to handle the cross references. The value of the map |
|
97 |
/// should be PRE_HEAP (-1) for each element. |
|
98 |
|
|
94 |
/// Constructor. |
|
95 |
/// \param map A map that assigns \c int values to the items. |
|
96 |
/// It is used internally to handle the cross references. |
|
97 |
/// The assigned value must be \c PRE_HEAP (<tt>-1</tt>) for each item. |
|
98 |
explicit KaryHeap(ItemIntMap &map, int K=32) : _iim(map), _K(K) {} |
|
99 | 99 |
|
100 |
/// \brief |
|
100 |
/// \brief Constructor. |
|
101 | 101 |
/// |
102 |
/// The constructor. |
|
103 |
/// \param _iim should be given to the constructor, since it is used |
|
104 |
/// internally to handle the cross references. The value of the map |
|
105 |
/// should be PRE_HEAP (-1) for each element. |
|
102 |
/// Constructor. |
|
103 |
/// \param map A map that assigns \c int values to the items. |
|
104 |
/// It is used internally to handle the cross references. |
|
105 |
/// The assigned value must be \c PRE_HEAP (<tt>-1</tt>) for each item. |
|
106 |
/// \param comp The function object used for comparing the priorities. |
|
107 |
KaryHeap(ItemIntMap &map, const Compare &comp, int K=32) |
|
108 |
: _iim(map), _comp(comp), _K(K) {} |
|
109 |
|
|
110 |
/// \brief The number of items stored in the heap. |
|
106 | 111 |
/// |
107 |
/// \param _comp The comparator function object. |
|
108 |
KaryHeap(ItemIntMap &_iim, const Compare &_comp, const int &_K=32) |
|
109 |
|
|
112 |
/// This function returns the number of items stored in the heap. |
|
113 |
int size() const { return _data.size(); } |
|
110 | 114 |
|
115 |
/// \brief Check if the heap is empty. |
|
116 |
/// |
|
117 |
/// This function returns \c true if the heap is empty. |
|
118 |
bool empty() const { return _data.empty(); } |
|
111 | 119 |
|
112 |
/// |
|
120 |
/// \brief Make the heap empty. |
|
113 | 121 |
/// |
114 |
/// \brief Returns the number of items stored in the heap. |
|
115 |
int size() const { return data.size(); } |
|
116 |
|
|
117 |
/// \brief Checks if the heap stores no items. |
|
118 |
/// |
|
119 |
/// Returns \c true if and only if the heap stores no items. |
|
120 |
bool empty() const { return data.empty(); } |
|
121 |
|
|
122 |
/// \brief Make empty this heap. |
|
123 |
/// |
|
124 |
/// Make empty this heap. It does not change the cross reference map. |
|
125 |
/// If you want to reuse what is not surely empty you should first clear |
|
126 |
/// the heap and after that you should set the cross reference map for |
|
127 |
/// each item to \c PRE_HEAP. |
|
128 |
|
|
122 |
/// This functon makes the heap empty. |
|
123 |
/// It does not change the cross reference map. If you want to reuse |
|
124 |
/// a heap that is not surely empty, you should first clear it and |
|
125 |
/// then you should set the cross reference map to \c PRE_HEAP |
|
126 |
/// for each item. |
|
127 |
void clear() { _data.clear(); } |
|
129 | 128 |
|
130 | 129 |
private: |
131 |
int parent(int i) { return (i-1)/K; } |
|
132 |
int first_child(int i) { return K*i+1; } |
|
130 |
int parent(int i) { return (i-1)/_K; } |
|
131 |
int firstChild(int i) { return _K*i+1; } |
|
133 | 132 |
|
134 | 133 |
bool less(const Pair &p1, const Pair &p2) const { |
135 |
return |
|
134 |
return _comp(p1.second, p2.second); |
|
136 | 135 |
} |
137 | 136 |
|
138 |
int |
|
137 |
int findMin(const int child, const int length) { |
|
139 | 138 |
int min=child, i=1; |
140 |
while( i<K && child+i<length ) { |
|
141 |
if( less(data[child+i], data[min]) ) |
|
139 |
while( i<_K && child+i<length ) { |
|
140 |
if( less(_data[child+i], _data[min]) ) |
|
142 | 141 |
min=child+i; |
143 | 142 |
++i; |
144 | 143 |
} |
145 | 144 |
return min; |
146 | 145 |
} |
147 | 146 |
|
148 |
void |
|
147 |
void bubbleUp(int hole, Pair p) { |
|
149 | 148 |
int par = parent(hole); |
150 |
while( hole>0 && less(p,data[par]) ) { |
|
151 |
move(data[par],hole); |
|
149 |
while( hole>0 && less(p,_data[par]) ) { |
|
150 |
move(_data[par],hole); |
|
152 | 151 |
hole = par; |
153 | 152 |
par = parent(hole); |
154 | 153 |
} |
155 | 154 |
move(p, hole); |
156 | 155 |
} |
157 | 156 |
|
158 |
void |
|
157 |
void bubbleDown(int hole, Pair p, int length) { |
|
159 | 158 |
if( length>1 ) { |
160 |
int child = |
|
159 |
int child = firstChild(hole); |
|
161 | 160 |
while( child<length ) { |
162 |
child = find_min(child, length); |
|
163 |
if( !less(data[child], p) ) |
|
161 |
child = findMin(child, length); |
|
162 |
if( !less(_data[child], p) ) |
|
164 | 163 |
goto ok; |
165 |
move( |
|
164 |
move(_data[child], hole); |
|
166 | 165 |
hole = child; |
167 |
child = |
|
166 |
child = firstChild(hole); |
|
168 | 167 |
} |
169 | 168 |
} |
170 | 169 |
ok: |
... | ... |
@@ -172,167 +171,169 @@ |
172 | 171 |
} |
173 | 172 |
|
174 | 173 |
void move(const Pair &p, int i) { |
175 |
data[i] = p; |
|
176 |
iim.set(p.first, i); |
|
174 |
_data[i] = p; |
|
175 |
_iim.set(p.first, i); |
|
177 | 176 |
} |
178 | 177 |
|
179 | 178 |
public: |
180 | 179 |
/// \brief Insert a pair of item and priority into the heap. |
181 | 180 |
/// |
182 |
/// |
|
181 |
/// This function inserts \c p.first to the heap with priority |
|
182 |
/// \c p.second. |
|
183 | 183 |
/// \param p The pair to insert. |
184 |
/// \pre \c p.first must not be stored in the heap. |
|
184 | 185 |
void push(const Pair &p) { |
185 |
int n = data.size(); |
|
186 |
data.resize(n+1); |
|
187 |
|
|
186 |
int n = _data.size(); |
|
187 |
_data.resize(n+1); |
|
188 |
bubbleUp(n, p); |
|
188 | 189 |
} |
189 | 190 |
|
190 |
/// \brief Insert an item into the heap with the given |
|
191 |
/// \brief Insert an item into the heap with the given priority. |
|
191 | 192 |
/// |
192 |
/// |
|
193 |
/// This function inserts the given item into the heap with the |
|
194 |
/// given priority. |
|
193 | 195 |
/// \param i The item to insert. |
194 | 196 |
/// \param p The priority of the item. |
197 |
/// \pre \e i must not be stored in the heap. |
|
195 | 198 |
void push(const Item &i, const Prio &p) { push(Pair(i,p)); } |
196 | 199 |
|
197 |
/// \brief |
|
200 |
/// \brief Return the item having minimum priority. |
|
198 | 201 |
/// |
199 |
/// This method returns the item with minimum priority relative to \c |
|
200 |
/// Compare. |
|
201 |
/// \pre The heap must be nonempty. |
|
202 |
Item top() const { return data[0].first; } |
|
202 |
/// This function returns the item having minimum priority. |
|
203 |
/// \pre The heap must be non-empty. |
|
204 |
Item top() const { return _data[0].first; } |
|
203 | 205 |
|
204 |
/// \brief |
|
206 |
/// \brief The minimum priority. |
|
205 | 207 |
/// |
206 |
/// It returns the minimum priority relative to \c Compare. |
|
207 |
/// \pre The heap must be nonempty. |
|
208 |
|
|
208 |
/// This function returns the minimum priority. |
|
209 |
/// \pre The heap must be non-empty. |
|
210 |
Prio prio() const { return _data[0].second; } |
|
209 | 211 |
|
210 |
/// \brief |
|
212 |
/// \brief Remove the item having minimum priority. |
|
211 | 213 |
/// |
212 |
/// This method deletes the item with minimum priority relative to \c |
|
213 |
/// Compare from the heap. |
|
214 |
/// This function removes the item having minimum priority. |
|
214 | 215 |
/// \pre The heap must be non-empty. |
215 | 216 |
void pop() { |
216 |
int n = data.size()-1; |
|
217 |
iim.set(data[0].first, POST_HEAP); |
|
218 |
if (n>0) bubble_down(0, data[n], n); |
|
219 |
data.pop_back(); |
|
217 |
int n = _data.size()-1; |
|
218 |
_iim.set(_data[0].first, POST_HEAP); |
|
219 |
if (n>0) bubbleDown(0, _data[n], n); |
|
220 |
_data.pop_back(); |
|
220 | 221 |
} |
221 | 222 |
|
222 |
/// \brief |
|
223 |
/// \brief Remove the given item from the heap. |
|
223 | 224 |
/// |
224 |
/// This method deletes item \c i from the heap. |
|
225 |
/// \param i The item to erase. |
|
226 |
/// |
|
225 |
/// This function removes the given item from the heap if it is |
|
226 |
/// already stored. |
|
227 |
/// \param i The item to delete. |
|
228 |
/// \pre \e i must be in the heap. |
|
227 | 229 |
void erase(const Item &i) { |
228 |
int h = iim[i]; |
|
229 |
int n = data.size()-1; |
|
230 |
|
|
230 |
int h = _iim[i]; |
|
231 |
int n = _data.size()-1; |
|
232 |
_iim.set(_data[h].first, POST_HEAP); |
|
231 | 233 |
if( h<n ) { |
232 |
if( less(data[parent(h)], data[n]) ) |
|
233 |
bubble_down(h, data[n], n); |
|
234 |
if( less(_data[parent(h)], _data[n]) ) |
|
235 |
bubbleDown(h, _data[n], n); |
|
234 | 236 |
else |
235 |
|
|
237 |
bubbleUp(h, _data[n]); |
|
236 | 238 |
} |
237 |
|
|
239 |
_data.pop_back(); |
|
238 | 240 |
} |
239 | 241 |
|
240 |
|
|
241 |
/// \brief Returns the priority of \c i. |
|
242 |
/// \brief The priority of the given item. |
|
242 | 243 |
/// |
243 |
/// This function returns the priority of item \c i. |
|
244 |
/// \pre \c i must be in the heap. |
|
244 |
/// This function returns the priority of the given item. |
|
245 | 245 |
/// \param i The item. |
246 |
/// \pre \e i must be in the heap. |
|
246 | 247 |
Prio operator[](const Item &i) const { |
247 |
int idx = iim[i]; |
|
248 |
return data[idx].second; |
|
248 |
int idx = _iim[i]; |
|
249 |
return _data[idx].second; |
|
249 | 250 |
} |
250 | 251 |
|
251 |
/// \brief \c i gets to the heap with priority \c p independently |
|
252 |
/// if \c i was already there. |
|
252 |
/// \brief Set the priority of an item or insert it, if it is |
|
253 |
/// not stored in the heap. |
|
253 | 254 |
/// |
254 |
/// This method calls \ref push(\c i, \c p) if \c i is not stored |
|
255 |
/// in the heap and sets the priority of \c i to \c p otherwise. |
|
255 |
/// This method sets the priority of the given item if it is |
|
256 |
/// already stored in the heap. Otherwise it inserts the given |
|
257 |
/// item into the heap with the given priority. |
|
256 | 258 |
/// \param i The item. |
257 | 259 |
/// \param p The priority. |
258 | 260 |
void set(const Item &i, const Prio &p) { |
259 |
int idx = |
|
261 |
int idx = _iim[i]; |
|
260 | 262 |
if( idx<0 ) |
261 | 263 |
push(i,p); |
262 |
else if( comp(p, data[idx].second) ) |
|
263 |
bubble_up(idx, Pair(i,p)); |
|
264 |
else if( _comp(p, _data[idx].second) ) |
|
265 |
bubbleUp(idx, Pair(i,p)); |
|
264 | 266 |
else |
265 |
|
|
267 |
bubbleDown(idx, Pair(i,p), _data.size()); |
|
266 | 268 |
} |
267 | 269 |
|
268 |
/// \brief |
|
270 |
/// \brief Decrease the priority of an item to the given value. |
|
269 | 271 |
/// |
270 |
/// This method decreases the priority of item \c i to \c p. |
|
271 |
/// \pre \c i must be stored in the heap with priority at least \c |
|
272 |
/// |
|
272 |
/// This function decreases the priority of an item to the given value. |
|
273 | 273 |
/// \param i The item. |
274 | 274 |
/// \param p The priority. |
275 |
/// \pre \e i must be stored in the heap with priority at least \e p. |
|
275 | 276 |
void decrease(const Item &i, const Prio &p) { |
276 |
int idx = iim[i]; |
|
277 |
bubble_up(idx, Pair(i,p)); |
|
277 |
int idx = _iim[i]; |
|
278 |
bubbleUp(idx, Pair(i,p)); |
|
278 | 279 |
} |
279 | 280 |
|
280 |
/// \brief |
|
281 |
/// \brief Increase the priority of an item to the given value. |
|
281 | 282 |
/// |
282 |
/// This method sets the priority of item \c i to \c p. |
|
283 |
/// \pre \c i must be stored in the heap with priority at most \c |
|
284 |
/// |
|
283 |
/// This function increases the priority of an item to the given value. |
|
285 | 284 |
/// \param i The item. |
286 | 285 |
/// \param p The priority. |
286 |
/// \pre \e i must be stored in the heap with priority at most \e p. |
|
287 | 287 |
void increase(const Item &i, const Prio &p) { |
288 |
int idx = iim[i]; |
|
289 |
bubble_down(idx, Pair(i,p), data.size()); |
|
288 |
int idx = _iim[i]; |
|
289 |
bubbleDown(idx, Pair(i,p), _data.size()); |
|
290 | 290 |
} |
291 | 291 |
|
292 |
/// \brief Returns if \c item is in, has already been in, or has |
|
293 |
/// never been in the heap. |
|
292 |
/// \brief Return the state of an item. |
|
294 | 293 |
/// |
295 |
/// This method returns PRE_HEAP if \c item has never been in the |
|
296 |
/// heap, IN_HEAP if it is in the heap at the moment, and POST_HEAP |
|
297 |
/// otherwise. In the latter case it is possible that \c item will |
|
298 |
/// get back to the heap again. |
|
294 |
/// This method returns \c PRE_HEAP if the given item has never |
|
295 |
/// been in the heap, \c IN_HEAP if it is in the heap at the moment, |
|
296 |
/// and \c POST_HEAP otherwise. |
|
297 |
/// In the latter case it is possible that the item will get back |
|
298 |
/// to the heap again. |
|
299 | 299 |
/// \param i The item. |
300 | 300 |
State state(const Item &i) const { |
301 |
int s = |
|
301 |
int s = _iim[i]; |
|
302 | 302 |
if (s>=0) s=0; |
303 | 303 |
return State(s); |
304 | 304 |
} |
305 | 305 |
|
306 |
/// \brief |
|
306 |
/// \brief Set the state of an item in the heap. |
|
307 | 307 |
/// |
308 |
/// Sets the state of the \c item in the heap. It can be used to |
|
309 |
/// manually clear the heap when it is important to achive the |
|
310 |
/// |
|
308 |
/// This function sets the state of the given item in the heap. |
|
309 |
/// It can be used to manually clear the heap when it is important |
|
310 |
/// to achive better time complexity. |
|
311 | 311 |
/// \param i The item. |
312 | 312 |
/// \param st The state. It should not be \c IN_HEAP. |
313 | 313 |
void state(const Item& i, State st) { |
314 | 314 |
switch (st) { |
315 |
case POST_HEAP: |
|
316 |
case PRE_HEAP: |
|
317 |
if (state(i) == IN_HEAP) erase(i); |
|
318 |
iim[i] = st; |
|
319 |
break; |
|
320 |
case IN_HEAP: |
|
321 |
|
|
315 |
case POST_HEAP: |
|
316 |
case PRE_HEAP: |
|
317 |
if (state(i) == IN_HEAP) erase(i); |
|
318 |
_iim[i] = st; |
|
319 |
break; |
|
320 |
case IN_HEAP: |
|
321 |
break; |
|
322 | 322 |
} |
323 | 323 |
} |
324 | 324 |
|
325 |
/// \brief |
|
325 |
/// \brief Replace an item in the heap. |
|
326 | 326 |
/// |
327 |
/// The \c i item is replaced with \c j item. The \c i item should |
|
328 |
/// be in the heap, while the \c j should be out of the heap. The |
|
329 |
/// \c i item will out of the heap and \c j will be in the heap |
|
330 |
/// with the same prioriority as prevoiusly the \c i item. |
|
327 |
/// This function replaces item \c i with item \c j. |
|
328 |
/// Item \c i must be in the heap, while \c j must be out of the heap. |
|
329 |
/// After calling this method, item \c i will be out of the |
|
330 |
/// heap and \c j will be in the heap with the same prioriority |
|
331 |
/// as item \c i had before. |
|
331 | 332 |
void replace(const Item& i, const Item& j) { |
332 |
int idx=iim[i]; |
|
333 |
iim.set(i, iim[j]); |
|
334 |
iim.set(j, idx); |
|
335 |
data[idx].first=j; |
|
333 |
int idx=_iim[i]; |
|
334 |
_iim.set(i, _iim[j]); |
|
335 |
_iim.set(j, idx); |
|
336 |
_data[idx].first=j; |
|
336 | 337 |
} |
337 | 338 |
|
338 | 339 |
}; // class KaryHeap |
1 |
/* -*- C++ -*- |
|
1 |
/* -*- mode: C++; indent-tabs-mode: nil; -*- |
|
2 | 2 |
* |
3 |
* This file is a part of LEMON, a generic C++ optimization library |
|
3 |
* This file is a part of LEMON, a generic C++ optimization library. |
|
4 | 4 |
* |
5 |
* Copyright (C) 2003- |
|
5 |
* Copyright (C) 2003-2009 |
|
6 | 6 |
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
7 | 7 |
* (Egervary Research Group on Combinatorial Optimization, EGRES). |
8 | 8 |
* |
... | ... |
@@ -20,217 +20,223 @@ |
20 | 20 |
#define LEMON_PAIRING_HEAP_H |
21 | 21 |
|
22 | 22 |
///\file |
23 |
///\ingroup auxdat |
|
24 |
///\brief Pairing Heap implementation. |
|
23 |
///\ingroup heaps |
|
24 |
///\brief Pairing heap implementation. |
|
25 | 25 |
|
26 | 26 |
#include <vector> |
27 |
#include <utility> |
|
27 | 28 |
#include <functional> |
28 | 29 |
#include <lemon/math.h> |
29 | 30 |
|
30 | 31 |
namespace lemon { |
31 | 32 |
|
32 |
/// \ingroup |
|
33 |
/// \ingroup heaps |
|
33 | 34 |
/// |
34 | 35 |
///\brief Pairing Heap. |
35 | 36 |
/// |
36 |
///This class implements the \e Pairing \e heap data structure. A \e heap |
|
37 |
///is a data structure for storing items with specified values called \e |
|
38 |
///priorities in such a way that finding the item with minimum priority is |
|
39 |
///efficient. \c Compare specifies the ordering of the priorities. In a heap |
|
40 |
/// |
|
37 |
/// This class implements the \e pairing \e heap data structure. |
|
38 |
/// It fully conforms to the \ref concepts::Heap "heap concept". |
|
41 | 39 |
/// |
42 |
///The methods \ref increase and \ref erase are not efficient in a Pairing |
|
43 |
///heap. In case of many calls to these operations, it is better to use a |
|
44 |
///\ref |
|
40 |
/// The methods \ref increase() and \ref erase() are not efficient |
|
41 |
/// in a pairing heap. In case of many calls of these operations, |
|
42 |
/// it is better to use other heap structure, e.g. \ref BinHeap |
|
43 |
/// "binary heap". |
|
45 | 44 |
/// |
46 |
///\param _Prio Type of the priority of the items. |
|
47 |
///\param _ItemIntMap A read and writable Item int map, used internally |
|
48 |
///to handle the cross references. |
|
49 |
///\param _Compare A class for the ordering of the priorities. The |
|
50 |
///default is \c std::less<_Prio>. |
|
51 |
/// |
|
52 |
///\sa BinHeap |
|
53 |
///\sa Dijkstra |
|
54 |
///\author Dorian Batha |
|
55 |
|
|
45 |
/// \tparam PR Type of the priorities of the items. |
|
46 |
/// \tparam IM A read-writable item map with \c int values, used |
|
47 |
/// internally to handle the cross references. |
|
48 |
/// \tparam CMP A functor class for comparing the priorities. |
|
49 |
/// The default is \c std::less<PR>. |
|
56 | 50 |
#ifdef DOXYGEN |
57 |
template <typename _Prio, |
|
58 |
typename _ItemIntMap, |
|
59 |
|
|
51 |
template <typename PR, typename IM, typename CMP> |
|
60 | 52 |
#else |
61 |
template <typename _Prio, |
|
62 |
typename _ItemIntMap, |
|
63 |
|
|
53 |
template <typename PR, typename IM, typename CMP = std::less<PR> > |
|
64 | 54 |
#endif |
65 | 55 |
class PairingHeap { |
66 | 56 |
public: |
67 |
typedef _ItemIntMap ItemIntMap; |
|
68 |
typedef _Prio Prio; |
|
57 |
/// Type of the item-int map. |
|
58 |
typedef IM ItemIntMap; |
|
59 |
/// Type of the priorities. |
|
60 |
typedef PR Prio; |
|
61 |
/// Type of the items stored in the heap. |
|
69 | 62 |
typedef typename ItemIntMap::Key Item; |
70 |
typedef std::pair<Item,Prio> Pair; |
|
71 |
typedef _Compare Compare; |
|
63 |
/// Functor type for comparing the priorities. |
|
64 |
typedef CMP Compare; |
|
65 |
|
|
66 |
/// \brief Type to represent the states of the items. |
|
67 |
/// |
|
68 |
/// Each item has a state associated to it. It can be "in heap", |
|
69 |
/// "pre-heap" or "post-heap". The latter two are indifferent from the |
|
70 |
/// heap's point of view, but may be useful to the user. |
|
71 |
/// |
|
72 |
/// The item-int map must be initialized in such way that it assigns |
|
73 |
/// \c PRE_HEAP (<tt>-1</tt>) to any element to be put in the heap. |
|
74 |
enum State { |
|
75 |
IN_HEAP = 0, ///< = 0. |
|
76 |
PRE_HEAP = -1, ///< = -1. |
|
77 |
POST_HEAP = -2 ///< = -2. |
|
78 |
}; |
|
72 | 79 |
|
73 | 80 |
private: |
74 | 81 |
class store; |
75 | 82 |
|
76 |
std::vector<store> container; |
|
77 |
int minimum; |
|
78 |
ItemIntMap &iimap; |
|
79 |
Compare comp; |
|
80 |
|
|
83 |
std::vector<store> _data; |
|
84 |
int _min; |
|
85 |
ItemIntMap &_iim; |
|
86 |
Compare _comp; |
|
87 |
int _num_items; |
|
81 | 88 |
|
82 | 89 |
public: |
83 |
///Status of the nodes |
|
84 |
enum State { |
|
85 |
///The node is in the heap |
|
86 |
IN_HEAP = 0, |
|
87 |
///The node has never been in the heap |
|
88 |
PRE_HEAP = -1, |
|
89 |
///The node was in the heap but it got out of it |
|
90 |
POST_HEAP = -2 |
|
91 |
|
|
90 |
/// \brief Constructor. |
|
91 |
/// |
|
92 |
/// Constructor. |
|
93 |
/// \param map A map that assigns \c int values to the items. |
|
94 |
/// It is used internally to handle the cross references. |
|
95 |
/// The assigned value must be \c PRE_HEAP (<tt>-1</tt>) for each item. |
|
96 |
explicit PairingHeap(ItemIntMap &map) |
|
97 |
: _min(0), _iim(map), _num_items(0) {} |
|
92 | 98 |
|
93 |
/// \brief |
|
99 |
/// \brief Constructor. |
|
94 | 100 |
/// |
95 |
/// \c _iimap should be given to the constructor, since it is |
|
96 |
/// used internally to handle the cross references. |
|
97 |
explicit PairingHeap(ItemIntMap &_iimap) |
|
98 |
: minimum(0), iimap(_iimap), num_items(0) {} |
|
99 |
|
|
100 |
/// \brief The constructor |
|
101 |
/// |
|
102 |
/// \c _iimap should be given to the constructor, since it is used |
|
103 |
/// internally to handle the cross references. \c _comp is an |
|
104 |
/// object for ordering of the priorities. |
|
105 |
PairingHeap(ItemIntMap &_iimap, const Compare &_comp) |
|
106 |
: minimum(0), iimap(_iimap), comp(_comp), num_items(0) {} |
|
101 |
/// Constructor. |
|
102 |
/// \param map A map that assigns \c int values to the items. |
|
103 |
/// It is used internally to handle the cross references. |
|
104 |
/// The assigned value must be \c PRE_HEAP (<tt>-1</tt>) for each item. |
|
105 |
/// \param comp The function object used for comparing the priorities. |
|
106 |
PairingHeap(ItemIntMap &map, const Compare &comp) |
|
107 |
: _min(0), _iim(map), _comp(comp), _num_items(0) {} |
|
107 | 108 |
|
108 | 109 |
/// \brief The number of items stored in the heap. |
109 | 110 |
/// |
110 |
/// Returns the number of items stored in the heap. |
|
111 |
int size() const { return num_items; } |
|
111 |
/// This function returns the number of items stored in the heap. |
|
112 |
int size() const { return _num_items; } |
|
112 | 113 |
|
113 |
/// \brief |
|
114 |
/// \brief Check if the heap is empty. |
|
114 | 115 |
/// |
115 |
/// Returns \c true if and only if the heap stores no items. |
|
116 |
bool empty() const { return num_items==0; } |
|
116 |
/// This function returns \c true if the heap is empty. |
|
117 |
bool empty() const { return _num_items==0; } |
|
117 | 118 |
|
118 |
/// \brief Make |
|
119 |
/// \brief Make the heap empty. |
|
119 | 120 |
/// |
120 |
/// Make empty this heap. It does not change the cross reference |
|
121 |
/// map. If you want to reuse a heap what is not surely empty you |
|
122 |
/// should first clear the heap and after that you should set the |
|
123 |
/// cross reference map for each item to \c PRE_HEAP. |
|
121 |
/// This functon makes the heap empty. |
|
122 |
/// It does not change the cross reference map. If you want to reuse |
|
123 |
/// a heap that is not surely empty, you should first clear it and |
|
124 |
/// then you should set the cross reference map to \c PRE_HEAP |
|
125 |
/// for each item. |
|
124 | 126 |
void clear() { |
125 |
container.clear(); |
|
126 |
minimum = 0; |
|
127 |
|
|
127 |
_data.clear(); |
|
128 |
_min = 0; |
|
129 |
_num_items = 0; |
|
128 | 130 |
} |
129 | 131 |
|
130 |
/// \brief \c item gets to the heap with priority \c value independently |
|
131 |
/// if \c item was already there. |
|
132 |
/// \brief Set the priority of an item or insert it, if it is |
|
133 |
/// not stored in the heap. |
|
132 | 134 |
/// |
133 |
/// This method calls \ref push(\c item, \c value) if \c item is not |
|
134 |
/// stored in the heap and it calls \ref decrease(\c item, \c value) or |
|
135 |
/// |
|
135 |
/// This method sets the priority of the given item if it is |
|
136 |
/// already stored in the heap. Otherwise it inserts the given |
|
137 |
/// item into the heap with the given priority. |
|
138 |
/// \param item The item. |
|
139 |
/// \param value The priority. |
|
136 | 140 |
void set (const Item& item, const Prio& value) { |
137 |
int i=iimap[item]; |
|
138 |
if ( i>=0 && container[i].in ) { |
|
139 |
if ( comp(value, container[i].prio) ) decrease(item, value); |
|
140 |
if ( comp(container[i].prio, value) ) increase(item, value); |
|
141 |
int i=_iim[item]; |
|
142 |
if ( i>=0 && _data[i].in ) { |
|
143 |
if ( _comp(value, _data[i].prio) ) decrease(item, value); |
|
144 |
if ( _comp(_data[i].prio, value) ) increase(item, value); |
|
141 | 145 |
} else push(item, value); |
142 | 146 |
} |
143 | 147 |
|
144 |
/// \brief |
|
148 |
/// \brief Insert an item into the heap with the given priority. |
|
145 | 149 |
/// |
146 |
/// Adds \c item to the heap with priority \c value. |
|
147 |
/// \pre \c item must not be stored in the heap. |
|
150 |
/// This function inserts the given item into the heap with the |
|
151 |
/// given priority. |
|
152 |
/// \param item The item to insert. |
|
153 |
/// \param value The priority of the item. |
|
154 |
/// \pre \e item must not be stored in the heap. |
|
148 | 155 |
void push (const Item& item, const Prio& value) { |
149 |
int i= |
|
156 |
int i=_iim[item]; |
|
150 | 157 |
if( i<0 ) { |
151 |
int s=container.size(); |
|
152 |
iimap.set(item, s); |
|
158 |
int s=_data.size(); |
|
159 |
_iim.set(item, s); |
|
153 | 160 |
store st; |
154 | 161 |
st.name=item; |
155 |
|
|
162 |
_data.push_back(st); |
|
156 | 163 |
i=s; |
157 | 164 |
} else { |
158 |
container[i].parent=container[i].child=-1; |
|
159 |
container[i].left_child=false; |
|
160 |
container[i].degree=0; |
|
161 |
container[i].in=true; |
|
165 |
_data[i].parent=_data[i].child=-1; |
|
166 |
_data[i].left_child=false; |
|
167 |
_data[i].degree=0; |
|
168 |
_data[i].in=true; |
|
162 | 169 |
} |
163 | 170 |
|
164 |
|
|
171 |
_data[i].prio=value; |
|
165 | 172 |
|
166 |
if ( num_items!=0 ) { |
|
167 |
if ( comp( value, container[minimum].prio) ) { |
|
168 |
fuse(i,minimum); |
|
169 |
minimum=i; |
|
173 |
if ( _num_items!=0 ) { |
|
174 |
if ( _comp( value, _data[_min].prio) ) { |
|
175 |
fuse(i,_min); |
|
176 |
_min=i; |
|
170 | 177 |
} |
171 |
else fuse( |
|
178 |
else fuse(_min,i); |
|
172 | 179 |
} |
173 |
else |
|
180 |
else _min=i; |
|
174 | 181 |
|
175 |
++ |
|
182 |
++_num_items; |
|
176 | 183 |
} |
177 | 184 |
|
178 |
/// \brief |
|
185 |
/// \brief Return the item having minimum priority. |
|
179 | 186 |
/// |
180 |
/// This method returns the item with minimum priority relative to \c |
|
181 |
/// Compare. |
|
182 |
/// \pre The heap must be nonempty. |
|
183 |
Item top() const { return container[minimum].name; } |
|
187 |
/// This function returns the item having minimum priority. |
|
188 |
/// \pre The heap must be non-empty. |
|
189 |
Item top() const { return _data[_min].name; } |
|
184 | 190 |
|
185 |
/// \brief |
|
191 |
/// \brief The minimum priority. |
|
186 | 192 |
/// |
187 |
/// It returns the minimum priority relative to \c Compare. |
|
188 |
/// \pre The heap must be nonempty. |
|
189 |
|
|
193 |
/// This function returns the minimum priority. |
|
194 |
/// \pre The heap must be non-empty. |
|
195 |
const Prio& prio() const { return _data[_min].prio; } |
|
190 | 196 |
|
191 |
/// \brief |
|
197 |
/// \brief The priority of the given item. |
|
192 | 198 |
/// |
193 |
/// It returns the priority of \c item. |
|
194 |
/// \pre \c item must be in the heap. |
|
199 |
/// This function returns the priority of the given item. |
|
200 |
/// \param item The item. |
|
201 |
/// \pre \e item must be in the heap. |
|
195 | 202 |
const Prio& operator[](const Item& item) const { |
196 |
return |
|
203 |
return _data[_iim[item]].prio; |
|
197 | 204 |
} |
198 | 205 |
|
199 |
/// \brief |
|
206 |
/// \brief Remove the item having minimum priority. |
|
200 | 207 |
/// |
201 |
/// This method deletes the item with minimum priority relative to \c |
|
202 |
/// Compare from the heap. |
|
208 |
/// This function removes the item having minimum priority. |
|
203 | 209 |
/// \pre The heap must be non-empty. |
204 | 210 |
void pop() { |
205 |
int TreeArray[ |
|
211 |
int TreeArray[_num_items]; |
|
206 | 212 |
int i=0, num_child=0, child_right = 0; |
207 |
|
|
213 |
_data[_min].in=false; |
|
208 | 214 |
|
209 |
if( -1!=container[minimum].child ) { |
|
210 |
i=container[minimum].child; |
|
215 |
if( -1!=_data[_min].child ) { |
|
216 |
i=_data[_min].child; |
|
211 | 217 |
TreeArray[num_child] = i; |
212 |
container[i].parent = -1; |
|
213 |
container[minimum].child = -1; |
|
218 |
_data[i].parent = -1; |
|
219 |
_data[_min].child = -1; |
|
214 | 220 |
|
215 | 221 |
++num_child; |
216 | 222 |
int ch=-1; |
217 |
while( container[i].child!=-1 ) { |
|
218 |
ch=container[i].child; |
|
219 |
|
|
223 |
while( _data[i].child!=-1 ) { |
|
224 |
ch=_data[i].child; |
|
225 |
if( _data[ch].left_child && i==_data[ch].parent ) { |
|
220 | 226 |
i=ch; |
221 | 227 |
//break; |
222 | 228 |
} else { |
223 |
if( container[ch].left_child ) { |
|
224 |
child_right=container[ch].parent; |
|
225 |
container[ch].parent = i; |
|
226 |
--container[i].degree; |
|
229 |
if( _data[ch].left_child ) { |
|
230 |
child_right=_data[ch].parent; |
|
231 |
_data[ch].parent = i; |
|
232 |
--_data[i].degree; |
|
227 | 233 |
} |
228 | 234 |
else { |
229 | 235 |
child_right=ch; |
230 |
container[i].child=-1; |
|
231 |
container[i].degree=0; |
|
236 |
_data[i].child=-1; |
|
237 |
_data[i].degree=0; |
|
232 | 238 |
} |
233 |
|
|
239 |
_data[child_right].parent = -1; |
|
234 | 240 |
TreeArray[num_child] = child_right; |
235 | 241 |
i = child_right; |
236 | 242 |
++num_child; |
... | ... |
@@ -239,8 +245,8 @@ |
239 | 245 |
|
240 | 246 |
int other; |
241 | 247 |
for( i=0; i<num_child-1; i+=2 ) { |
242 |
if ( !comp(container[TreeArray[i]].prio, |
|
243 |
container[TreeArray[i+1]].prio) ) { |
|
248 |
if ( !_comp(_data[TreeArray[i]].prio, |
|
249 |
_data[TreeArray[i+1]].prio) ) { |
|
244 | 250 |
other=TreeArray[i]; |
245 | 251 |
TreeArray[i]=TreeArray[i+1]; |
246 | 252 |
TreeArray[i+1]=other; |
... | ... |
@@ -250,8 +256,8 @@ |
250 | 256 |
|
251 | 257 |
i = (0==(num_child % 2)) ? num_child-2 : num_child-1; |
252 | 258 |
while(i>=2) { |
253 |
if ( comp(container[TreeArray[i]].prio, |
|
254 |
container[TreeArray[i-2]].prio) ) { |
|
259 |
if ( _comp(_data[TreeArray[i]].prio, |
|
260 |
_data[TreeArray[i-2]].prio) ) { |
|
255 | 261 |
other=TreeArray[i]; |
256 | 262 |
TreeArray[i]=TreeArray[i-2]; |
257 | 263 |
TreeArray[i-2]=other; |
... | ... |
@@ -259,88 +265,91 @@ |
259 | 265 |
fuse( TreeArray[i-2], TreeArray[i] ); |
260 | 266 |
i-=2; |
261 | 267 |
} |
262 |
|
|
268 |
_min = TreeArray[0]; |
|
263 | 269 |
} |
264 | 270 |
|
265 | 271 |
if ( 0==num_child ) { |
266 |
|
|
272 |
_min = _data[_min].child; |
|
267 | 273 |
} |
268 | 274 |
|
269 |
if ( |
|
275 |
if (_min >= 0) _data[_min].left_child = false; |
|
270 | 276 |
|
271 |
-- |
|
277 |
--_num_items; |
|
272 | 278 |
} |
273 | 279 |
|
274 |
/// \brief |
|
280 |
/// \brief Remove the given item from the heap. |
|
275 | 281 |
/// |
276 |
/// This method deletes \c item from the heap, if \c item was already |
|
277 |
/// stored in the heap. It is quite inefficient in Pairing heaps. |
|
282 |
/// This function removes the given item from the heap if it is |
|
283 |
/// already stored. |
|
284 |
/// \param item The item to delete. |
|
285 |
/// \pre \e item must be in the heap. |
|
278 | 286 |
void erase (const Item& item) { |
279 |
int i=iimap[item]; |
|
280 |
if ( i>=0 && container[i].in ) { |
|
281 |
|
|
287 |
int i=_iim[item]; |
|
288 |
if ( i>=0 && _data[i].in ) { |
|
289 |
decrease( item, _data[_min].prio-1 ); |
|
282 | 290 |
pop(); |
283 | 291 |
} |
284 | 292 |
} |
285 | 293 |
|
286 |
/// \brief |
|
294 |
/// \brief Decrease the priority of an item to the given value. |
|
287 | 295 |
/// |
288 |
/// This method decreases the priority of \c item to \c value. |
|
289 |
/// \pre \c item must be stored in the heap with priority at least \c |
|
290 |
/// |
|
296 |
/// This function decreases the priority of an item to the given value. |
|
297 |
/// \param item The item. |
|
298 |
/// \param value The priority. |
|
299 |
/// \pre \e item must be stored in the heap with priority at least \e value. |
|
291 | 300 |
void decrease (Item item, const Prio& value) { |
292 |
int i=iimap[item]; |
|
293 |
container[i].prio=value; |
|
294 |
int |
|
301 |
int i=_iim[item]; |
|
302 |
_data[i].prio=value; |
|
303 |
int p=_data[i].parent; |
|
295 | 304 |
|
296 |
if( container[i].left_child && i!=container[p].child ) { |
|
297 |
p=container[p].parent; |
|
305 |
if( _data[i].left_child && i!=_data[p].child ) { |
|
306 |
p=_data[p].parent; |
|
298 | 307 |
} |
299 | 308 |
|
300 |
if ( p!=-1 && |
|
309 |
if ( p!=-1 && _comp(value,_data[p].prio) ) { |
|
301 | 310 |
cut(i,p); |
302 |
if ( comp(container[minimum].prio,value) ) { |
|
303 |
fuse(minimum,i); |
|
311 |
if ( _comp(_data[_min].prio,value) ) { |
|
312 |
fuse(_min,i); |
|
304 | 313 |
} else { |
305 |
fuse(i,minimum); |
|
306 |
minimum=i; |
|
314 |
fuse(i,_min); |
|
315 |
_min=i; |
|
307 | 316 |
} |
308 | 317 |
} |
309 | 318 |
} |
310 | 319 |
|
311 |
/// \brief |
|
320 |
/// \brief Increase the priority of an item to the given value. |
|
312 | 321 |
/// |
313 |
/// This method sets the priority of \c item to \c value. Though |
|
314 |
/// there is no precondition on the priority of \c item, this |
|
315 |
/// method should be used only if it is indeed necessary to increase |
|
316 |
/// (relative to \c Compare) the priority of \c item, because this |
|
317 |
/// |
|
322 |
/// This function increases the priority of an item to the given value. |
|
323 |
/// \param item The item. |
|
324 |
/// \param value The priority. |
|
325 |
/// \pre \e item must be stored in the heap with priority at most \e value. |
|
318 | 326 |
void increase (Item item, const Prio& value) { |
319 | 327 |
erase(item); |
320 | 328 |
push(item,value); |
321 | 329 |
} |
322 | 330 |
|
323 |
/// \brief Returns if \c item is in, has already been in, or has never |
|
324 |
/// been in the heap. |
|
331 |
/// \brief Return the state of an item. |
|
325 | 332 |
/// |
326 |
/// This method returns PRE_HEAP if \c item has never been in the |
|
327 |
/// heap, IN_HEAP if it is in the heap at the moment, and POST_HEAP |
|
328 |
/// otherwise. In the latter case it is possible that \c item will |
|
329 |
/// get back to the heap again. |
|
333 |
/// This method returns \c PRE_HEAP if the given item has never |
|
334 |
/// been in the heap, \c IN_HEAP if it is in the heap at the moment, |
|
335 |
/// and \c POST_HEAP otherwise. |
|
336 |
/// In the latter case it is possible that the item will get back |
|
337 |
/// to the heap again. |
|
338 |
/// \param item The item. |
|
330 | 339 |
State state(const Item &item) const { |
331 |
int i= |
|
340 |
int i=_iim[item]; |
|
332 | 341 |
if( i>=0 ) { |
333 |
if( |
|
342 |
if( _data[i].in ) i=0; |
|
334 | 343 |
else i=-2; |
335 | 344 |
} |
336 | 345 |
return State(i); |
337 | 346 |
} |
338 | 347 |
|
339 |
/// \brief |
|
348 |
/// \brief Set the state of an item in the heap. |
|
340 | 349 |
/// |
341 |
/// Sets the state of the \c item in the heap. It can be used to |
|
342 |
/// manually clear the heap when it is important to achive the |
|
343 |
/// |
|
350 |
/// This function sets the state of the given item in the heap. |
|
351 |
/// It can be used to manually clear the heap when it is important |
|
352 |
/// to achive better time complexity. |
|
344 | 353 |
/// \param i The item. |
345 | 354 |
/// \param st The state. It should not be \c IN_HEAP. |
346 | 355 |
void state(const Item& i, State st) { |
... | ... |
@@ -348,7 +357,7 @@ |
348 | 357 |
case POST_HEAP: |
349 | 358 |
case PRE_HEAP: |
350 | 359 |
if (state(i) == IN_HEAP) erase(i); |
351 |
|
|
360 |
_iim[i]=st; |
|
352 | 361 |
break; |
353 | 362 |
case IN_HEAP: |
354 | 363 |
break; |
... | ... |
@@ -359,95 +368,95 @@ |
359 | 368 |
|
360 | 369 |
void cut(int a, int b) { |
361 | 370 |
int child_a; |
362 |
switch ( |
|
371 |
switch (_data[a].degree) { |
|
363 | 372 |
case 2: |
364 |
child_a = container[container[a].child].parent; |
|
365 |
if( container[a].left_child ) { |
|
366 |
container[child_a].left_child=true; |
|
367 |
container[b].child=child_a; |
|
368 |
|
|
373 |
child_a = _data[_data[a].child].parent; |
|
374 |
if( _data[a].left_child ) { |
|
375 |
_data[child_a].left_child=true; |
|
376 |
_data[b].child=child_a; |
|
377 |
_data[child_a].parent=_data[a].parent; |
|
369 | 378 |
} |
370 | 379 |
else { |
371 |
container[child_a].left_child=false; |
|
372 |
container[child_a].parent=b; |
|
373 |
if( a!=container[b].child ) |
|
374 |
container[container[b].child].parent=child_a; |
|
380 |
_data[child_a].left_child=false; |
|
381 |
_data[child_a].parent=b; |
|
382 |
if( a!=_data[b].child ) |
|
383 |
_data[_data[b].child].parent=child_a; |
|
375 | 384 |
else |
376 |
|
|
385 |
_data[b].child=child_a; |
|
377 | 386 |
} |
378 |
--container[a].degree; |
|
379 |
container[container[a].child].parent=a; |
|
387 |
--_data[a].degree; |
|
388 |
_data[_data[a].child].parent=a; |
|
380 | 389 |
break; |
381 | 390 |
|
382 | 391 |
case 1: |
383 |
child_a = container[a].child; |
|
384 |
if( !container[child_a].left_child ) { |
|
385 |
--container[a].degree; |
|
386 |
if( container[a].left_child ) { |
|
387 |
container[child_a].left_child=true; |
|
388 |
container[child_a].parent=container[a].parent; |
|
389 |
|
|
392 |
child_a = _data[a].child; |
|
393 |
if( !_data[child_a].left_child ) { |
|
394 |
--_data[a].degree; |
|
395 |
if( _data[a].left_child ) { |
|
396 |
_data[child_a].left_child=true; |
|
397 |
_data[child_a].parent=_data[a].parent; |
|
398 |
_data[b].child=child_a; |
|
390 | 399 |
} |
391 | 400 |
else { |
392 |
container[child_a].left_child=false; |
|
393 |
container[child_a].parent=b; |
|
394 |
if( a!=container[b].child ) |
|
395 |
container[container[b].child].parent=child_a; |
|
401 |
_data[child_a].left_child=false; |
|
402 |
_data[child_a].parent=b; |
|
403 |
if( a!=_data[b].child ) |
|
404 |
_data[_data[b].child].parent=child_a; |
|
396 | 405 |
else |
397 |
|
|
406 |
_data[b].child=child_a; |
|
398 | 407 |
} |
399 |
|
|
408 |
_data[a].child=-1; |
|
400 | 409 |
} |
401 | 410 |
else { |
402 |
--container[b].degree; |
|
403 |
if( container[a].left_child ) { |
|
404 |
container[b].child = |
|
405 |
(1==container[b].degree) ? container[a].parent : -1; |
|
411 |
--_data[b].degree; |
|
412 |
if( _data[a].left_child ) { |
|
413 |
_data[b].child = |
|
414 |
(1==_data[b].degree) ? _data[a].parent : -1; |
|
406 | 415 |
} else { |
407 |
if (1==container[b].degree) |
|
408 |
container[container[b].child].parent=b; |
|
416 |
if (1==_data[b].degree) |
|
417 |
_data[_data[b].child].parent=b; |
|
409 | 418 |
else |
410 |
|
|
419 |
_data[b].child=-1; |
|
411 | 420 |
} |
412 | 421 |
} |
413 | 422 |
break; |
414 | 423 |
|
415 | 424 |
case 0: |
416 |
--container[b].degree; |
|
417 |
if( container[a].left_child ) { |
|
418 |
container[b].child = |
|
419 |
(0!=container[b].degree) ? container[a].parent : -1; |
|
425 |
--_data[b].degree; |
|
426 |
if( _data[a].left_child ) { |
|
427 |
_data[b].child = |
|
428 |
(0!=_data[b].degree) ? _data[a].parent : -1; |
|
420 | 429 |
} else { |
421 |
if( 0!=container[b].degree ) |
|
422 |
container[container[b].child].parent=b; |
|
430 |
if( 0!=_data[b].degree ) |
|
431 |
_data[_data[b].child].parent=b; |
|
423 | 432 |
else |
424 |
|
|
433 |
_data[b].child=-1; |
|
425 | 434 |
} |
426 | 435 |
break; |
427 | 436 |
} |
428 |
container[a].parent=-1; |
|
429 |
container[a].left_child=false; |
|
437 |
_data[a].parent=-1; |
|
438 |
_data[a].left_child=false; |
|
430 | 439 |
} |
431 | 440 |
|
432 | 441 |
void fuse(int a, int b) { |
433 |
int child_a = container[a].child; |
|
434 |
int child_b = container[b].child; |
|
435 |
container[a].child=b; |
|
436 |
container[b].parent=a; |
|
437 |
|
|
442 |
int child_a = _data[a].child; |
|
443 |
int child_b = _data[b].child; |
|
444 |
_data[a].child=b; |
|
445 |
_data[b].parent=a; |
|
446 |
_data[b].left_child=true; |
|
438 | 447 |
|
439 | 448 |
if( -1!=child_a ) { |
440 |
container[b].child=child_a; |
|
441 |
container[child_a].parent=b; |
|
442 |
container[child_a].left_child=false; |
|
443 |
++container[b].degree; |
|
449 |
_data[b].child=child_a; |
|
450 |
_data[child_a].parent=b; |
|
451 |
_data[child_a].left_child=false; |
|
452 |
++_data[b].degree; |
|
444 | 453 |
|
445 | 454 |
if( -1!=child_b ) { |
446 |
container[b].child=child_b; |
|
447 |
container[child_b].parent=child_a; |
|
455 |
_data[b].child=child_b; |
|
456 |
_data[child_b].parent=child_a; |
|
448 | 457 |
} |
449 | 458 |
} |
450 |
else { ++ |
|
459 |
else { ++_data[a].degree; } |
|
451 | 460 |
} |
452 | 461 |
|
453 | 462 |
class store { |
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