1 // Set implementation -*- C++ -*-
3 // Copyright (C) 2001, 2002, 2004 Free Software Foundation, Inc.
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
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12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
16 // You should have received a copy of the GNU General Public License along
17 // with this library; see the file COPYING. If not, write to the Free
18 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
21 // As a special exception, you may use this file as part of a free software
22 // library without restriction. Specifically, if other files instantiate
23 // templates or use macros or inline functions from this file, or you compile
24 // this file and link it with other files to produce an executable, this
25 // file does not by itself cause the resulting executable to be covered by
26 // the GNU General Public License. This exception does not however
27 // invalidate any other reasons why the executable file might be covered by
28 // the GNU General Public License.
33 * Hewlett-Packard Company
35 * Permission to use, copy, modify, distribute and sell this software
36 * and its documentation for any purpose is hereby granted without fee,
37 * provided that the above copyright notice appear in all copies and
38 * that both that copyright notice and this permission notice appear
39 * in supporting documentation. Hewlett-Packard Company makes no
40 * representations about the suitability of this software for any
41 * purpose. It is provided "as is" without express or implied warranty.
44 * Copyright (c) 1996,1997
45 * Silicon Graphics Computer Systems, Inc.
47 * Permission to use, copy, modify, distribute and sell this software
48 * and its documentation for any purpose is hereby granted without fee,
49 * provided that the above copyright notice appear in all copies and
50 * that both that copyright notice and this permission notice appear
51 * in supporting documentation. Silicon Graphics makes no
52 * representations about the suitability of this software for any
53 * purpose. It is provided "as is" without express or implied warranty.
57 * This is an internal header file, included by other library headers.
58 * You should not attempt to use it directly.
64 #include <bits/concept_check.h>
66 namespace _GLIBCXX_STD
68 // Forward declarations of operators < and ==, needed for friend declaration.
69 template<class _Key
, class _Compare
= less
<_Key
>,
70 class _Alloc
= allocator
<_Key
> >
73 template<class _Key
, class _Compare
, class _Alloc
>
75 operator==(const set
<_Key
,_Compare
,_Alloc
>& __x
,
76 const set
<_Key
,_Compare
,_Alloc
>& __y
);
78 template<class _Key
, class _Compare
, class _Alloc
>
80 operator<(const set
<_Key
,_Compare
,_Alloc
>& __x
,
81 const set
<_Key
,_Compare
,_Alloc
>& __y
);
84 * @brief A standard container made up of unique keys, which can be
85 * retrieved in logarithmic time.
88 * @ingroup Assoc_containers
90 * Meets the requirements of a <a href="tables.html#65">container</a>, a
91 * <a href="tables.html#66">reversible container</a>, and an
92 * <a href="tables.html#69">associative container</a> (using unique keys).
94 * Sets support bidirectional iterators.
96 * @param Key Type of key objects.
97 * @param Compare Comparison function object type, defaults to less<Key>.
98 * @param Alloc Allocator type, defaults to allocator<Key>.
101 * The private tree data is declared exactly the same way for set and
102 * multiset; the distinction is made entirely in how the tree functions are
103 * called (*_unique versus *_equal, same as the standard).
106 template<class _Key
, class _Compare
, class _Alloc
>
109 // concept requirements
110 __glibcxx_class_requires(_Key
, _SGIAssignableConcept
)
111 __glibcxx_class_requires4(_Compare
, bool, _Key
, _Key
,
112 _BinaryFunctionConcept
)
118 typedef _Key key_type
;
119 typedef _Key value_type
;
120 typedef _Compare key_compare
;
121 typedef _Compare value_compare
;
125 typedef _Rb_tree
<key_type
, value_type
,
126 _Identity
<value_type
>, key_compare
, _Alloc
> _Rep_type
;
127 _Rep_type _M_t
; // red-black tree representing set
130 /// Iterator-related typedefs.
131 typedef typename
_Alloc::pointer pointer
;
132 typedef typename
_Alloc::const_pointer const_pointer
;
133 typedef typename
_Alloc::reference reference
;
134 typedef typename
_Alloc::const_reference const_reference
;
135 // _GLIBCXX_RESOLVE_LIB_DEFECTS
136 // DR 103. set::iterator is required to be modifiable,
137 // but this allows modification of keys.
138 typedef typename
_Rep_type::const_iterator iterator
;
139 typedef typename
_Rep_type::const_iterator const_iterator
;
140 typedef typename
_Rep_type::const_reverse_iterator reverse_iterator
;
141 typedef typename
_Rep_type::const_reverse_iterator const_reverse_iterator
;
142 typedef typename
_Rep_type::size_type size_type
;
143 typedef typename
_Rep_type::difference_type difference_type
;
144 typedef typename
_Rep_type::allocator_type allocator_type
;
147 // allocation/deallocation
148 /// Default constructor creates no elements.
150 : _M_t(_Compare(), allocator_type()) {}
153 * @brief Default constructor creates no elements.
155 * @param comp Comparator to use.
156 * @param a Allocator to use.
158 explicit set(const _Compare
& __comp
,
159 const allocator_type
& __a
= allocator_type())
160 : _M_t(__comp
, __a
) {}
163 * @brief Builds a %set from a range.
164 * @param first An input iterator.
165 * @param last An input iterator.
167 * Create a %set consisting of copies of the elements from [first,last).
168 * This is linear in N if the range is already sorted, and NlogN
169 * otherwise (where N is distance(first,last)).
171 template<class _InputIterator
>
172 set(_InputIterator __first
, _InputIterator __last
)
173 : _M_t(_Compare(), allocator_type())
174 { _M_t
.insert_unique(__first
, __last
); }
177 * @brief Builds a %set from a range.
178 * @param first An input iterator.
179 * @param last An input iterator.
180 * @param comp A comparison functor.
181 * @param a An allocator object.
183 * Create a %set consisting of copies of the elements from [first,last).
184 * This is linear in N if the range is already sorted, and NlogN
185 * otherwise (where N is distance(first,last)).
187 template<class _InputIterator
>
188 set(_InputIterator __first
, _InputIterator __last
,
189 const _Compare
& __comp
,
190 const allocator_type
& __a
= allocator_type())
192 { _M_t
.insert_unique(__first
, __last
); }
195 * @brief Set copy constructor.
196 * @param x A %set of identical element and allocator types.
198 * The newly-created %set uses a copy of the allocation object used
201 set(const set
<_Key
,_Compare
,_Alloc
>& __x
)
205 * @brief Set assignment operator.
206 * @param x A %set of identical element and allocator types.
208 * All the elements of @a x are copied, but unlike the copy constructor,
209 * the allocator object is not copied.
211 set
<_Key
,_Compare
,_Alloc
>&
212 operator=(const set
<_Key
, _Compare
, _Alloc
>& __x
)
220 /// Returns the comparison object with which the %set was constructed.
223 { return _M_t
.key_comp(); }
224 /// Returns the comparison object with which the %set was constructed.
227 { return _M_t
.key_comp(); }
228 /// Returns the allocator object with which the %set was constructed.
230 get_allocator() const
231 { return _M_t
.get_allocator(); }
234 * Returns a read/write iterator that points to the first element in the
235 * %set. Iteration is done in ascending order according to the keys.
239 { return _M_t
.begin(); }
242 * Returns a read/write iterator that points one past the last element in
243 * the %set. Iteration is done in ascending order according to the keys.
247 { return _M_t
.end(); }
250 * Returns a read/write reverse iterator that points to the last element
251 * in the %set. Iteration is done in descending order according to the
256 { return _M_t
.rbegin(); }
259 * Returns a read-only (constant) reverse iterator that points to the
260 * last pair in the %map. Iteration is done in descending order
261 * according to the keys.
265 { return _M_t
.rend(); }
267 /// Returns true if the %set is empty.
270 { return _M_t
.empty(); }
272 /// Returns the size of the %set.
275 { return _M_t
.size(); }
277 /// Returns the maximum size of the %set.
280 { return _M_t
.max_size(); }
283 * @brief Swaps data with another %set.
284 * @param x A %set of the same element and allocator types.
286 * This exchanges the elements between two sets in constant time.
287 * (It is only swapping a pointer, an integer, and an instance of
288 * the @c Compare type (which itself is often stateless and empty), so it
289 * should be quite fast.)
290 * Note that the global std::swap() function is specialized such that
291 * std::swap(s1,s2) will feed to this function.
294 swap(set
<_Key
,_Compare
,_Alloc
>& __x
)
295 { _M_t
.swap(__x
._M_t
); }
299 * @brief Attempts to insert an element into the %set.
300 * @param x Element to be inserted.
301 * @return A pair, of which the first element is an iterator that points
302 * to the possibly inserted element, and the second is a bool
303 * that is true if the element was actually inserted.
305 * This function attempts to insert an element into the %set. A %set
306 * relies on unique keys and thus an element is only inserted if it is
307 * not already present in the %set.
309 * Insertion requires logarithmic time.
312 insert(const value_type
& __x
)
314 pair
<typename
_Rep_type::iterator
, bool> __p
= _M_t
.insert_unique(__x
);
315 return pair
<iterator
, bool>(__p
.first
, __p
.second
);
319 * @brief Attempts to insert an element into the %set.
320 * @param position An iterator that serves as a hint as to where the
321 * element should be inserted.
322 * @param x Element to be inserted.
323 * @return An iterator that points to the element with key of @a x (may
324 * or may not be the element passed in).
326 * This function is not concerned about whether the insertion took place,
327 * and thus does not return a boolean like the single-argument insert()
328 * does. Note that the first parameter is only a hint and can
329 * potentially improve the performance of the insertion process. A bad
330 * hint would cause no gains in efficiency.
332 * See http://gcc.gnu.org/onlinedocs/libstdc++/23_containers/howto.html#4
333 * for more on "hinting".
335 * Insertion requires logarithmic time (if the hint is not taken).
338 insert(iterator __position
, const value_type
& __x
)
340 typedef typename
_Rep_type::iterator _Rep_iterator
;
341 return _M_t
.insert_unique((_Rep_iterator
&)__position
, __x
);
345 * @brief A template function that attemps to insert a range of elements.
346 * @param first Iterator pointing to the start of the range to be
348 * @param last Iterator pointing to the end of the range.
350 * Complexity similar to that of the range constructor.
352 template<class _InputIterator
>
354 insert(_InputIterator __first
, _InputIterator __last
)
355 { _M_t
.insert_unique(__first
, __last
); }
358 * @brief Erases an element from a %set.
359 * @param position An iterator pointing to the element to be erased.
361 * This function erases an element, pointed to by the given iterator,
362 * from a %set. Note that this function only erases the element, and
363 * that if the element is itself a pointer, the pointed-to memory is not
364 * touched in any way. Managing the pointer is the user's responsibilty.
367 erase(iterator __position
)
369 typedef typename
_Rep_type::iterator _Rep_iterator
;
370 _M_t
.erase((_Rep_iterator
&)__position
);
374 * @brief Erases elements according to the provided key.
375 * @param x Key of element to be erased.
376 * @return The number of elements erased.
378 * This function erases all the elements located by the given key from
380 * Note that this function only erases the element, and that if
381 * the element is itself a pointer, the pointed-to memory is not touched
382 * in any way. Managing the pointer is the user's responsibilty.
385 erase(const key_type
& __x
) { return _M_t
.erase(__x
); }
388 * @brief Erases a [first,last) range of elements from a %set.
389 * @param first Iterator pointing to the start of the range to be
391 * @param last Iterator pointing to the end of the range to be erased.
393 * This function erases a sequence of elements from a %set.
394 * Note that this function only erases the element, and that if
395 * the element is itself a pointer, the pointed-to memory is not touched
396 * in any way. Managing the pointer is the user's responsibilty.
399 erase(iterator __first
, iterator __last
)
401 typedef typename
_Rep_type::iterator _Rep_iterator
;
402 _M_t
.erase((_Rep_iterator
&)__first
, (_Rep_iterator
&)__last
);
406 * Erases all elements in a %set. Note that this function only erases
407 * the elements, and that if the elements themselves are pointers, the
408 * pointed-to memory is not touched in any way. Managing the pointer is
409 * the user's responsibilty.
418 * @brief Finds the number of elements.
419 * @param x Element to located.
420 * @return Number of elements with specified key.
422 * This function only makes sense for multisets; for set the result will
423 * either be 0 (not present) or 1 (present).
426 count(const key_type
& __x
) const
427 { return _M_t
.find(__x
) == _M_t
.end() ? 0 : 1; }
429 // _GLIBCXX_RESOLVE_LIB_DEFECTS
430 // 214. set::find() missing const overload
433 * @brief Tries to locate an element in a %set.
434 * @param x Element to be located.
435 * @return Iterator pointing to sought-after element, or end() if not
438 * This function takes a key and tries to locate the element with which
439 * the key matches. If successful the function returns an iterator
440 * pointing to the sought after element. If unsuccessful it returns the
441 * past-the-end ( @c end() ) iterator.
444 find(const key_type
& __x
)
445 { return _M_t
.find(__x
); }
448 find(const key_type
& __x
) const
449 { return _M_t
.find(__x
); }
454 * @brief Finds the beginning of a subsequence matching given key.
455 * @param x Key to be located.
456 * @return Iterator pointing to first element equal to or greater
457 * than key, or end().
459 * This function returns the first element of a subsequence of elements
460 * that matches the given key. If unsuccessful it returns an iterator
461 * pointing to the first element that has a greater value than given key
462 * or end() if no such element exists.
465 lower_bound(const key_type
& __x
)
466 { return _M_t
.lower_bound(__x
); }
469 lower_bound(const key_type
& __x
) const
470 { return _M_t
.lower_bound(__x
); }
475 * @brief Finds the end of a subsequence matching given key.
476 * @param x Key to be located.
477 * @return Iterator pointing to the first element
478 * greater than key, or end().
481 upper_bound(const key_type
& __x
)
482 { return _M_t
.upper_bound(__x
); }
485 upper_bound(const key_type
& __x
) const
486 { return _M_t
.upper_bound(__x
); }
491 * @brief Finds a subsequence matching given key.
492 * @param x Key to be located.
493 * @return Pair of iterators that possibly points to the subsequence
494 * matching given key.
496 * This function is equivalent to
498 * std::make_pair(c.lower_bound(val),
499 * c.upper_bound(val))
501 * (but is faster than making the calls separately).
503 * This function probably only makes sense for multisets.
505 pair
<iterator
,iterator
>
506 equal_range(const key_type
& __x
)
507 { return _M_t
.equal_range(__x
); }
509 pair
<const_iterator
,const_iterator
>
510 equal_range(const key_type
& __x
) const
511 { return _M_t
.equal_range(__x
); }
514 template<class _K1
, class _C1
, class _A1
>
516 operator== (const set
<_K1
,_C1
,_A1
>&, const set
<_K1
,_C1
,_A1
>&);
518 template<class _K1
, class _C1
, class _A1
>
520 operator< (const set
<_K1
,_C1
,_A1
>&, const set
<_K1
,_C1
,_A1
>&);
525 * @brief Set equality comparison.
527 * @param y A %set of the same type as @a x.
528 * @return True iff the size and elements of the sets are equal.
530 * This is an equivalence relation. It is linear in the size of the sets.
531 * Sets are considered equivalent if their sizes are equal, and if
532 * corresponding elements compare equal.
534 template<class _Key
, class _Compare
, class _Alloc
>
536 operator==(const set
<_Key
,_Compare
,_Alloc
>& __x
,
537 const set
<_Key
,_Compare
,_Alloc
>& __y
)
538 { return __x
._M_t
== __y
._M_t
; }
541 * @brief Set ordering relation.
543 * @param y A %set of the same type as @a x.
544 * @return True iff @a x is lexicographically less than @a y.
546 * This is a total ordering relation. It is linear in the size of the
547 * maps. The elements must be comparable with @c <.
549 * See std::lexicographical_compare() for how the determination is made.
551 template<class _Key
, class _Compare
, class _Alloc
>
553 operator<(const set
<_Key
,_Compare
,_Alloc
>& __x
,
554 const set
<_Key
,_Compare
,_Alloc
>& __y
)
555 { return __x
._M_t
< __y
._M_t
; }
557 /// Returns !(x == y).
558 template<class _Key
, class _Compare
, class _Alloc
>
560 operator!=(const set
<_Key
,_Compare
,_Alloc
>& __x
,
561 const set
<_Key
,_Compare
,_Alloc
>& __y
)
562 { return !(__x
== __y
); }
565 template<class _Key
, class _Compare
, class _Alloc
>
567 operator>(const set
<_Key
,_Compare
,_Alloc
>& __x
,
568 const set
<_Key
,_Compare
,_Alloc
>& __y
)
569 { return __y
< __x
; }
572 template<class _Key
, class _Compare
, class _Alloc
>
574 operator<=(const set
<_Key
,_Compare
,_Alloc
>& __x
,
575 const set
<_Key
,_Compare
,_Alloc
>& __y
)
576 { return !(__y
< __x
); }
579 template<class _Key
, class _Compare
, class _Alloc
>
581 operator>=(const set
<_Key
,_Compare
,_Alloc
>& __x
,
582 const set
<_Key
,_Compare
,_Alloc
>& __y
)
583 { return !(__x
< __y
); }
585 /// See std::set::swap().
586 template<class _Key
, class _Compare
, class _Alloc
>
588 swap(set
<_Key
,_Compare
,_Alloc
>& __x
, set
<_Key
,_Compare
,_Alloc
>& __y
)