1 // Set implementation -*- C++ -*-
3 // Copyright (C) 2001, 2002, 2004, 2005, 2006 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
8 // Free Software Foundation; either version 2, or (at your option)
11 // This library is distributed in the hope that it will be useful,
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, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
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 _GLIBCXX_BEGIN_NESTED_NAMESPACE(std
, _GLIBCXX_STD
)
69 * @brief A standard container made up of unique keys, which can be
70 * retrieved in logarithmic time.
73 * @ingroup Assoc_containers
75 * Meets the requirements of a <a href="tables.html#65">container</a>, a
76 * <a href="tables.html#66">reversible container</a>, and an
77 * <a href="tables.html#69">associative container</a> (using unique keys).
79 * Sets support bidirectional iterators.
81 * @param Key Type of key objects.
82 * @param Compare Comparison function object type, defaults to less<Key>.
83 * @param Alloc Allocator type, defaults to allocator<Key>.
86 * The private tree data is declared exactly the same way for set and
87 * multiset; the distinction is made entirely in how the tree functions are
88 * called (*_unique versus *_equal, same as the standard).
91 template<class _Key
, class _Compare
= std::less
<_Key
>,
92 class _Alloc
= std::allocator
<_Key
> >
95 // concept requirements
96 typedef typename
_Alloc::value_type _Alloc_value_type
;
97 __glibcxx_class_requires(_Key
, _SGIAssignableConcept
)
98 __glibcxx_class_requires4(_Compare
, bool, _Key
, _Key
,
99 _BinaryFunctionConcept
)
100 __glibcxx_class_requires2(_Key
, _Alloc_value_type
, _SameTypeConcept
)
106 typedef _Key key_type
;
107 typedef _Key value_type
;
108 typedef _Compare key_compare
;
109 typedef _Compare value_compare
;
110 typedef _Alloc allocator_type
;
114 typedef typename
_Alloc::template rebind
<_Key
>::other _Key_alloc_type
;
116 typedef _Rb_tree
<key_type
, value_type
, _Identity
<value_type
>,
117 key_compare
, _Key_alloc_type
> _Rep_type
;
118 _Rep_type _M_t
; // red-black tree representing set
122 /// Iterator-related typedefs.
123 typedef typename
_Key_alloc_type::pointer pointer
;
124 typedef typename
_Key_alloc_type::const_pointer const_pointer
;
125 typedef typename
_Key_alloc_type::reference reference
;
126 typedef typename
_Key_alloc_type::const_reference const_reference
;
127 // _GLIBCXX_RESOLVE_LIB_DEFECTS
128 // DR 103. set::iterator is required to be modifiable,
129 // but this allows modification of keys.
130 typedef typename
_Rep_type::const_iterator iterator
;
131 typedef typename
_Rep_type::const_iterator const_iterator
;
132 typedef typename
_Rep_type::const_reverse_iterator reverse_iterator
;
133 typedef typename
_Rep_type::const_reverse_iterator const_reverse_iterator
;
134 typedef typename
_Rep_type::size_type size_type
;
135 typedef typename
_Rep_type::difference_type difference_type
;
138 // allocation/deallocation
139 /// Default constructor creates no elements.
141 : _M_t(_Compare(), allocator_type()) {}
144 * @brief Default constructor creates no elements.
146 * @param comp Comparator to use.
147 * @param a Allocator to use.
150 set(const _Compare
& __comp
,
151 const allocator_type
& __a
= allocator_type())
152 : _M_t(__comp
, __a
) {}
155 * @brief Builds a %set from a range.
156 * @param first An input iterator.
157 * @param last An input iterator.
159 * Create a %set consisting of copies of the elements from [first,last).
160 * This is linear in N if the range is already sorted, and NlogN
161 * otherwise (where N is distance(first,last)).
163 template<class _InputIterator
>
164 set(_InputIterator __first
, _InputIterator __last
)
165 : _M_t(_Compare(), allocator_type())
166 { _M_t
._M_insert_unique(__first
, __last
); }
169 * @brief Builds a %set from a range.
170 * @param first An input iterator.
171 * @param last An input iterator.
172 * @param comp A comparison functor.
173 * @param a An allocator object.
175 * Create a %set consisting of copies of the elements from [first,last).
176 * This is linear in N if the range is already sorted, and NlogN
177 * otherwise (where N is distance(first,last)).
179 template<class _InputIterator
>
180 set(_InputIterator __first
, _InputIterator __last
,
181 const _Compare
& __comp
,
182 const allocator_type
& __a
= allocator_type())
184 { _M_t
._M_insert_unique(__first
, __last
); }
187 * @brief Set copy constructor.
188 * @param x A %set of identical element and allocator types.
190 * The newly-created %set uses a copy of the allocation object used
193 set(const set
<_Key
,_Compare
,_Alloc
>& __x
)
197 * @brief Set assignment operator.
198 * @param x A %set of identical element and allocator types.
200 * All the elements of @a x are copied, but unlike the copy constructor,
201 * the allocator object is not copied.
203 set
<_Key
,_Compare
,_Alloc
>&
204 operator=(const set
<_Key
, _Compare
, _Alloc
>& __x
)
212 /// Returns the comparison object with which the %set was constructed.
215 { return _M_t
.key_comp(); }
216 /// Returns the comparison object with which the %set was constructed.
219 { return _M_t
.key_comp(); }
220 /// Returns the allocator object with which the %set was constructed.
222 get_allocator() const
223 { return _M_t
.get_allocator(); }
226 * Returns a read/write iterator that points to the first element in the
227 * %set. Iteration is done in ascending order according to the keys.
231 { return _M_t
.begin(); }
234 * Returns a read/write iterator that points one past the last element in
235 * the %set. Iteration is done in ascending order according to the keys.
239 { return _M_t
.end(); }
242 * Returns a read/write reverse iterator that points to the last element
243 * in the %set. Iteration is done in descending order according to the
248 { return _M_t
.rbegin(); }
251 * Returns a read-only (constant) reverse iterator that points to the
252 * last pair in the %map. Iteration is done in descending order
253 * according to the keys.
257 { return _M_t
.rend(); }
259 /// Returns true if the %set is empty.
262 { return _M_t
.empty(); }
264 /// Returns the size of the %set.
267 { return _M_t
.size(); }
269 /// Returns the maximum size of the %set.
272 { return _M_t
.max_size(); }
275 * @brief Swaps data with another %set.
276 * @param x A %set of the same element and allocator types.
278 * This exchanges the elements between two sets in constant time.
279 * (It is only swapping a pointer, an integer, and an instance of
280 * the @c Compare type (which itself is often stateless and empty), so it
281 * should be quite fast.)
282 * Note that the global std::swap() function is specialized such that
283 * std::swap(s1,s2) will feed to this function.
286 swap(set
<_Key
,_Compare
,_Alloc
>& __x
)
287 { _M_t
.swap(__x
._M_t
); }
291 * @brief Attempts to insert an element into the %set.
292 * @param x Element to be inserted.
293 * @return A pair, of which the first element is an iterator that points
294 * to the possibly inserted element, and the second is a bool
295 * that is true if the element was actually inserted.
297 * This function attempts to insert an element into the %set. A %set
298 * relies on unique keys and thus an element is only inserted if it is
299 * not already present in the %set.
301 * Insertion requires logarithmic time.
303 std::pair
<iterator
,bool>
304 insert(const value_type
& __x
)
306 std::pair
<typename
_Rep_type::iterator
, bool> __p
=
307 _M_t
._M_insert_unique(__x
);
308 return std::pair
<iterator
, bool>(__p
.first
, __p
.second
);
312 * @brief Attempts to insert an element into the %set.
313 * @param position An iterator that serves as a hint as to where the
314 * element should be inserted.
315 * @param x Element to be inserted.
316 * @return An iterator that points to the element with key of @a x (may
317 * or may not be the element passed in).
319 * This function is not concerned about whether the insertion took place,
320 * and thus does not return a boolean like the single-argument insert()
321 * does. Note that the first parameter is only a hint and can
322 * potentially improve the performance of the insertion process. A bad
323 * hint would cause no gains in efficiency.
325 * See http://gcc.gnu.org/onlinedocs/libstdc++/23_containers/howto.html#4
326 * for more on "hinting".
328 * Insertion requires logarithmic time (if the hint is not taken).
331 insert(iterator __position
, const value_type
& __x
)
332 { return _M_t
._M_insert_unique(__position
, __x
); }
335 * @brief A template function that attemps to insert a range of elements.
336 * @param first Iterator pointing to the start of the range to be
338 * @param last Iterator pointing to the end of the range.
340 * Complexity similar to that of the range constructor.
342 template<class _InputIterator
>
344 insert(_InputIterator __first
, _InputIterator __last
)
345 { _M_t
._M_insert_unique(__first
, __last
); }
348 * @brief Erases an element from a %set.
349 * @param position An iterator pointing to the element to be erased.
351 * This function erases an element, pointed to by the given iterator,
352 * from a %set. Note that this function only erases the element, and
353 * that if the element is itself a pointer, the pointed-to memory is not
354 * touched in any way. Managing the pointer is the user's responsibilty.
357 erase(iterator __position
)
358 { _M_t
.erase(__position
); }
361 * @brief Erases elements according to the provided key.
362 * @param x Key of element to be erased.
363 * @return The number of elements erased.
365 * This function erases all the elements located by the given key from
367 * Note that this function only erases the element, and that if
368 * the element is itself a pointer, the pointed-to memory is not touched
369 * in any way. Managing the pointer is the user's responsibilty.
372 erase(const key_type
& __x
)
373 { return _M_t
.erase(__x
); }
376 * @brief Erases a [first,last) range of elements from a %set.
377 * @param first Iterator pointing to the start of the range to be
379 * @param last Iterator pointing to the end of the range to be erased.
381 * This function erases a sequence of elements from a %set.
382 * Note that this function only erases the element, and that if
383 * the element is itself a pointer, the pointed-to memory is not touched
384 * in any way. Managing the pointer is the user's responsibilty.
387 erase(iterator __first
, iterator __last
)
388 { _M_t
.erase(__first
, __last
); }
391 * Erases all elements in a %set. Note that this function only erases
392 * the elements, and that if the elements themselves are pointers, the
393 * pointed-to memory is not touched in any way. Managing the pointer is
394 * the user's responsibilty.
403 * @brief Finds the number of elements.
404 * @param x Element to located.
405 * @return Number of elements with specified key.
407 * This function only makes sense for multisets; for set the result will
408 * either be 0 (not present) or 1 (present).
411 count(const key_type
& __x
) const
412 { return _M_t
.find(__x
) == _M_t
.end() ? 0 : 1; }
414 // _GLIBCXX_RESOLVE_LIB_DEFECTS
415 // 214. set::find() missing const overload
418 * @brief Tries to locate an element in a %set.
419 * @param x Element to be located.
420 * @return Iterator pointing to sought-after element, or end() if not
423 * This function takes a key and tries to locate the element with which
424 * the key matches. If successful the function returns an iterator
425 * pointing to the sought after element. If unsuccessful it returns the
426 * past-the-end ( @c end() ) iterator.
429 find(const key_type
& __x
)
430 { return _M_t
.find(__x
); }
433 find(const key_type
& __x
) const
434 { return _M_t
.find(__x
); }
439 * @brief Finds the beginning of a subsequence matching given key.
440 * @param x Key to be located.
441 * @return Iterator pointing to first element equal to or greater
442 * than key, or end().
444 * This function returns the first element of a subsequence of elements
445 * that matches the given key. If unsuccessful it returns an iterator
446 * pointing to the first element that has a greater value than given key
447 * or end() if no such element exists.
450 lower_bound(const key_type
& __x
)
451 { return _M_t
.lower_bound(__x
); }
454 lower_bound(const key_type
& __x
) const
455 { return _M_t
.lower_bound(__x
); }
460 * @brief Finds the end of a subsequence matching given key.
461 * @param x Key to be located.
462 * @return Iterator pointing to the first element
463 * greater than key, or end().
466 upper_bound(const key_type
& __x
)
467 { return _M_t
.upper_bound(__x
); }
470 upper_bound(const key_type
& __x
) const
471 { return _M_t
.upper_bound(__x
); }
476 * @brief Finds a subsequence matching given key.
477 * @param x Key to be located.
478 * @return Pair of iterators that possibly points to the subsequence
479 * matching given key.
481 * This function is equivalent to
483 * std::make_pair(c.lower_bound(val),
484 * c.upper_bound(val))
486 * (but is faster than making the calls separately).
488 * This function probably only makes sense for multisets.
490 std::pair
<iterator
, iterator
>
491 equal_range(const key_type
& __x
)
492 { return _M_t
.equal_range(__x
); }
494 std::pair
<const_iterator
, const_iterator
>
495 equal_range(const key_type
& __x
) const
496 { return _M_t
.equal_range(__x
); }
499 template<class _K1
, class _C1
, class _A1
>
501 operator== (const set
<_K1
, _C1
, _A1
>&, const set
<_K1
, _C1
, _A1
>&);
503 template<class _K1
, class _C1
, class _A1
>
505 operator< (const set
<_K1
, _C1
, _A1
>&, const set
<_K1
, _C1
, _A1
>&);
510 * @brief Set equality comparison.
512 * @param y A %set of the same type as @a x.
513 * @return True iff the size and elements of the sets are equal.
515 * This is an equivalence relation. It is linear in the size of the sets.
516 * Sets are considered equivalent if their sizes are equal, and if
517 * corresponding elements compare equal.
519 template<class _Key
, class _Compare
, class _Alloc
>
521 operator==(const set
<_Key
, _Compare
, _Alloc
>& __x
,
522 const set
<_Key
, _Compare
, _Alloc
>& __y
)
523 { return __x
._M_t
== __y
._M_t
; }
526 * @brief Set ordering relation.
528 * @param y A %set of the same type as @a x.
529 * @return True iff @a x is lexicographically less than @a y.
531 * This is a total ordering relation. It is linear in the size of the
532 * maps. The elements must be comparable with @c <.
534 * See std::lexicographical_compare() for how the determination is made.
536 template<class _Key
, class _Compare
, class _Alloc
>
538 operator<(const set
<_Key
, _Compare
, _Alloc
>& __x
,
539 const set
<_Key
, _Compare
, _Alloc
>& __y
)
540 { return __x
._M_t
< __y
._M_t
; }
542 /// Returns !(x == y).
543 template<class _Key
, class _Compare
, class _Alloc
>
545 operator!=(const set
<_Key
, _Compare
, _Alloc
>& __x
,
546 const set
<_Key
, _Compare
, _Alloc
>& __y
)
547 { return !(__x
== __y
); }
550 template<class _Key
, class _Compare
, class _Alloc
>
552 operator>(const set
<_Key
, _Compare
, _Alloc
>& __x
,
553 const set
<_Key
, _Compare
, _Alloc
>& __y
)
554 { return __y
< __x
; }
557 template<class _Key
, class _Compare
, class _Alloc
>
559 operator<=(const set
<_Key
, _Compare
, _Alloc
>& __x
,
560 const set
<_Key
, _Compare
, _Alloc
>& __y
)
561 { return !(__y
< __x
); }
564 template<class _Key
, class _Compare
, class _Alloc
>
566 operator>=(const set
<_Key
, _Compare
, _Alloc
>& __x
,
567 const set
<_Key
, _Compare
, _Alloc
>& __y
)
568 { return !(__x
< __y
); }
570 /// See std::set::swap().
571 template<class _Key
, class _Compare
, class _Alloc
>
573 swap(set
<_Key
, _Compare
, _Alloc
>& __x
, set
<_Key
, _Compare
, _Alloc
>& __y
)
576 _GLIBCXX_END_NESTED_NAMESPACE