1 // Set implementation -*- C++ -*-
3 // Copyright (C) 2001, 2002, 2004, 2005 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
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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
= std::less
<_Key
>,
70 class _Alloc
= std::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 typedef typename
_Alloc::value_type _Alloc_value_type
;
111 __glibcxx_class_requires(_Key
, _SGIAssignableConcept
)
112 __glibcxx_class_requires4(_Compare
, bool, _Key
, _Key
,
113 _BinaryFunctionConcept
)
114 __glibcxx_class_requires2(_Key
, _Alloc_value_type
, _SameTypeConcept
)
120 typedef _Key key_type
;
121 typedef _Key value_type
;
122 typedef _Compare key_compare
;
123 typedef _Compare value_compare
;
124 typedef _Alloc allocator_type
;
128 typedef typename
_Alloc::template rebind
<_Key
>::other _Key_alloc_type
;
130 typedef _Rb_tree
<key_type
, value_type
, _Identity
<value_type
>,
131 key_compare
, _Key_alloc_type
> _Rep_type
;
132 _Rep_type _M_t
; // red-black tree representing set
136 /// Iterator-related typedefs.
137 typedef typename
_Key_alloc_type::pointer pointer
;
138 typedef typename
_Key_alloc_type::const_pointer const_pointer
;
139 typedef typename
_Key_alloc_type::reference reference
;
140 typedef typename
_Key_alloc_type::const_reference const_reference
;
141 // _GLIBCXX_RESOLVE_LIB_DEFECTS
142 // DR 103. set::iterator is required to be modifiable,
143 // but this allows modification of keys.
144 typedef typename
_Rep_type::const_iterator iterator
;
145 typedef typename
_Rep_type::const_iterator const_iterator
;
146 typedef typename
_Rep_type::const_reverse_iterator reverse_iterator
;
147 typedef typename
_Rep_type::const_reverse_iterator const_reverse_iterator
;
148 typedef typename
_Rep_type::size_type size_type
;
149 typedef typename
_Rep_type::difference_type difference_type
;
152 // allocation/deallocation
153 /// Default constructor creates no elements.
155 : _M_t(_Compare(), allocator_type()) {}
158 * @brief Default constructor creates no elements.
160 * @param comp Comparator to use.
161 * @param a Allocator to use.
164 set(const _Compare
& __comp
,
165 const allocator_type
& __a
= allocator_type())
166 : _M_t(__comp
, __a
) {}
169 * @brief Builds a %set from a range.
170 * @param first An input iterator.
171 * @param last An input iterator.
173 * Create a %set consisting of copies of the elements from [first,last).
174 * This is linear in N if the range is already sorted, and NlogN
175 * otherwise (where N is distance(first,last)).
177 template<class _InputIterator
>
178 set(_InputIterator __first
, _InputIterator __last
)
179 : _M_t(_Compare(), allocator_type())
180 { _M_t
.insert_unique(__first
, __last
); }
183 * @brief Builds a %set from a range.
184 * @param first An input iterator.
185 * @param last An input iterator.
186 * @param comp A comparison functor.
187 * @param a An allocator object.
189 * Create a %set consisting of copies of the elements from [first,last).
190 * This is linear in N if the range is already sorted, and NlogN
191 * otherwise (where N is distance(first,last)).
193 template<class _InputIterator
>
194 set(_InputIterator __first
, _InputIterator __last
,
195 const _Compare
& __comp
,
196 const allocator_type
& __a
= allocator_type())
198 { _M_t
.insert_unique(__first
, __last
); }
201 * @brief Set copy constructor.
202 * @param x A %set of identical element and allocator types.
204 * The newly-created %set uses a copy of the allocation object used
207 set(const set
<_Key
,_Compare
,_Alloc
>& __x
)
211 * @brief Set assignment operator.
212 * @param x A %set of identical element and allocator types.
214 * All the elements of @a x are copied, but unlike the copy constructor,
215 * the allocator object is not copied.
217 set
<_Key
,_Compare
,_Alloc
>&
218 operator=(const set
<_Key
, _Compare
, _Alloc
>& __x
)
226 /// Returns the comparison object with which the %set was constructed.
229 { return _M_t
.key_comp(); }
230 /// Returns the comparison object with which the %set was constructed.
233 { return _M_t
.key_comp(); }
234 /// Returns the allocator object with which the %set was constructed.
236 get_allocator() const
237 { return _M_t
.get_allocator(); }
240 * Returns a read/write iterator that points to the first element in the
241 * %set. Iteration is done in ascending order according to the keys.
245 { return _M_t
.begin(); }
248 * Returns a read/write iterator that points one past the last element in
249 * the %set. Iteration is done in ascending order according to the keys.
253 { return _M_t
.end(); }
256 * Returns a read/write reverse iterator that points to the last element
257 * in the %set. Iteration is done in descending order according to the
262 { return _M_t
.rbegin(); }
265 * Returns a read-only (constant) reverse iterator that points to the
266 * last pair in the %map. Iteration is done in descending order
267 * according to the keys.
271 { return _M_t
.rend(); }
273 /// Returns true if the %set is empty.
276 { return _M_t
.empty(); }
278 /// Returns the size of the %set.
281 { return _M_t
.size(); }
283 /// Returns the maximum size of the %set.
286 { return _M_t
.max_size(); }
289 * @brief Swaps data with another %set.
290 * @param x A %set of the same element and allocator types.
292 * This exchanges the elements between two sets in constant time.
293 * (It is only swapping a pointer, an integer, and an instance of
294 * the @c Compare type (which itself is often stateless and empty), so it
295 * should be quite fast.)
296 * Note that the global std::swap() function is specialized such that
297 * std::swap(s1,s2) will feed to this function.
300 swap(set
<_Key
,_Compare
,_Alloc
>& __x
)
301 { _M_t
.swap(__x
._M_t
); }
305 * @brief Attempts to insert an element into the %set.
306 * @param x Element to be inserted.
307 * @return A pair, of which the first element is an iterator that points
308 * to the possibly inserted element, and the second is a bool
309 * that is true if the element was actually inserted.
311 * This function attempts to insert an element into the %set. A %set
312 * relies on unique keys and thus an element is only inserted if it is
313 * not already present in the %set.
315 * Insertion requires logarithmic time.
317 std::pair
<iterator
,bool>
318 insert(const value_type
& __x
)
320 std::pair
<typename
_Rep_type::iterator
, bool> __p
=
321 _M_t
.insert_unique(__x
);
322 return std::pair
<iterator
, bool>(__p
.first
, __p
.second
);
326 * @brief Attempts to insert an element into the %set.
327 * @param position An iterator that serves as a hint as to where the
328 * element should be inserted.
329 * @param x Element to be inserted.
330 * @return An iterator that points to the element with key of @a x (may
331 * or may not be the element passed in).
333 * This function is not concerned about whether the insertion took place,
334 * and thus does not return a boolean like the single-argument insert()
335 * does. Note that the first parameter is only a hint and can
336 * potentially improve the performance of the insertion process. A bad
337 * hint would cause no gains in efficiency.
339 * See http://gcc.gnu.org/onlinedocs/libstdc++/23_containers/howto.html#4
340 * for more on "hinting".
342 * Insertion requires logarithmic time (if the hint is not taken).
345 insert(iterator __position
, const value_type
& __x
)
347 typedef typename
_Rep_type::iterator _Rep_iterator
;
348 return _M_t
.insert_unique((_Rep_iterator
&)__position
, __x
);
352 * @brief A template function that attemps to insert a range of elements.
353 * @param first Iterator pointing to the start of the range to be
355 * @param last Iterator pointing to the end of the range.
357 * Complexity similar to that of the range constructor.
359 template<class _InputIterator
>
361 insert(_InputIterator __first
, _InputIterator __last
)
362 { _M_t
.insert_unique(__first
, __last
); }
365 * @brief Erases an element from a %set.
366 * @param position An iterator pointing to the element to be erased.
368 * This function erases an element, pointed to by the given iterator,
369 * from a %set. Note that this function only erases the element, and
370 * that if the element is itself a pointer, the pointed-to memory is not
371 * touched in any way. Managing the pointer is the user's responsibilty.
374 erase(iterator __position
)
376 typedef typename
_Rep_type::iterator _Rep_iterator
;
377 _M_t
.erase((_Rep_iterator
&)__position
);
381 * @brief Erases elements according to the provided key.
382 * @param x Key of element to be erased.
383 * @return The number of elements erased.
385 * This function erases all the elements located by the given key from
387 * Note that this function only erases the element, and that if
388 * the element is itself a pointer, the pointed-to memory is not touched
389 * in any way. Managing the pointer is the user's responsibilty.
392 erase(const key_type
& __x
) { return _M_t
.erase(__x
); }
395 * @brief Erases a [first,last) range of elements from a %set.
396 * @param first Iterator pointing to the start of the range to be
398 * @param last Iterator pointing to the end of the range to be erased.
400 * This function erases a sequence of elements from a %set.
401 * Note that this function only erases the element, and that if
402 * the element is itself a pointer, the pointed-to memory is not touched
403 * in any way. Managing the pointer is the user's responsibilty.
406 erase(iterator __first
, iterator __last
)
408 typedef typename
_Rep_type::iterator _Rep_iterator
;
409 _M_t
.erase((_Rep_iterator
&)__first
, (_Rep_iterator
&)__last
);
413 * Erases all elements in a %set. Note that this function only erases
414 * the elements, and that if the elements themselves are pointers, the
415 * pointed-to memory is not touched in any way. Managing the pointer is
416 * the user's responsibilty.
425 * @brief Finds the number of elements.
426 * @param x Element to located.
427 * @return Number of elements with specified key.
429 * This function only makes sense for multisets; for set the result will
430 * either be 0 (not present) or 1 (present).
433 count(const key_type
& __x
) const
434 { return _M_t
.find(__x
) == _M_t
.end() ? 0 : 1; }
436 // _GLIBCXX_RESOLVE_LIB_DEFECTS
437 // 214. set::find() missing const overload
440 * @brief Tries to locate an element in a %set.
441 * @param x Element to be located.
442 * @return Iterator pointing to sought-after element, or end() if not
445 * This function takes a key and tries to locate the element with which
446 * the key matches. If successful the function returns an iterator
447 * pointing to the sought after element. If unsuccessful it returns the
448 * past-the-end ( @c end() ) iterator.
451 find(const key_type
& __x
)
452 { return _M_t
.find(__x
); }
455 find(const key_type
& __x
) const
456 { return _M_t
.find(__x
); }
461 * @brief Finds the beginning of a subsequence matching given key.
462 * @param x Key to be located.
463 * @return Iterator pointing to first element equal to or greater
464 * than key, or end().
466 * This function returns the first element of a subsequence of elements
467 * that matches the given key. If unsuccessful it returns an iterator
468 * pointing to the first element that has a greater value than given key
469 * or end() if no such element exists.
472 lower_bound(const key_type
& __x
)
473 { return _M_t
.lower_bound(__x
); }
476 lower_bound(const key_type
& __x
) const
477 { return _M_t
.lower_bound(__x
); }
482 * @brief Finds the end of a subsequence matching given key.
483 * @param x Key to be located.
484 * @return Iterator pointing to the first element
485 * greater than key, or end().
488 upper_bound(const key_type
& __x
)
489 { return _M_t
.upper_bound(__x
); }
492 upper_bound(const key_type
& __x
) const
493 { return _M_t
.upper_bound(__x
); }
498 * @brief Finds a subsequence matching given key.
499 * @param x Key to be located.
500 * @return Pair of iterators that possibly points to the subsequence
501 * matching given key.
503 * This function is equivalent to
505 * std::make_pair(c.lower_bound(val),
506 * c.upper_bound(val))
508 * (but is faster than making the calls separately).
510 * This function probably only makes sense for multisets.
512 std::pair
<iterator
, iterator
>
513 equal_range(const key_type
& __x
)
514 { return _M_t
.equal_range(__x
); }
516 std::pair
<const_iterator
, const_iterator
>
517 equal_range(const key_type
& __x
) const
518 { return _M_t
.equal_range(__x
); }
521 template<class _K1
, class _C1
, class _A1
>
523 operator== (const set
<_K1
, _C1
, _A1
>&, const set
<_K1
, _C1
, _A1
>&);
525 template<class _K1
, class _C1
, class _A1
>
527 operator< (const set
<_K1
, _C1
, _A1
>&, const set
<_K1
, _C1
, _A1
>&);
532 * @brief Set equality comparison.
534 * @param y A %set of the same type as @a x.
535 * @return True iff the size and elements of the sets are equal.
537 * This is an equivalence relation. It is linear in the size of the sets.
538 * Sets are considered equivalent if their sizes are equal, and if
539 * corresponding elements compare equal.
541 template<class _Key
, class _Compare
, class _Alloc
>
543 operator==(const set
<_Key
, _Compare
, _Alloc
>& __x
,
544 const set
<_Key
, _Compare
, _Alloc
>& __y
)
545 { return __x
._M_t
== __y
._M_t
; }
548 * @brief Set ordering relation.
550 * @param y A %set of the same type as @a x.
551 * @return True iff @a x is lexicographically less than @a y.
553 * This is a total ordering relation. It is linear in the size of the
554 * maps. The elements must be comparable with @c <.
556 * See std::lexicographical_compare() for how the determination is made.
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
._M_t
< __y
._M_t
; }
564 /// Returns !(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 !(__x
== __y
); }
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 !(__y
< __x
); }
586 template<class _Key
, class _Compare
, class _Alloc
>
588 operator>=(const set
<_Key
, _Compare
, _Alloc
>& __x
,
589 const set
<_Key
, _Compare
, _Alloc
>& __y
)
590 { return !(__x
< __y
); }
592 /// See std::set::swap().
593 template<class _Key
, class _Compare
, class _Alloc
>
595 swap(set
<_Key
, _Compare
, _Alloc
>& __x
, set
<_Key
, _Compare
, _Alloc
>& __y
)