1 // Set implementation -*- C++ -*-
3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
4 // Free Software Foundation, Inc.
6 // This file is part of the GNU ISO C++ Library. This library is free
7 // software; you can redistribute it and/or modify it under the
8 // terms of the GNU General Public License as published by the
9 // Free Software Foundation; either version 3, or (at your option)
12 // This library is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
17 // Under Section 7 of GPL version 3, you are granted additional
18 // permissions described in the GCC Runtime Library Exception, version
19 // 3.1, as published by the Free Software Foundation.
21 // You should have received a copy of the GNU General Public License and
22 // a copy of the GCC Runtime Library Exception along with this program;
23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
24 // <http://www.gnu.org/licenses/>.
29 * Hewlett-Packard Company
31 * Permission to use, copy, modify, distribute and sell this software
32 * and its documentation for any purpose is hereby granted without fee,
33 * provided that the above copyright notice appear in all copies and
34 * that both that copyright notice and this permission notice appear
35 * in supporting documentation. Hewlett-Packard Company makes no
36 * representations about the suitability of this software for any
37 * purpose. It is provided "as is" without express or implied warranty.
40 * Copyright (c) 1996,1997
41 * Silicon Graphics Computer Systems, Inc.
43 * Permission to use, copy, modify, distribute and sell this software
44 * and its documentation for any purpose is hereby granted without fee,
45 * provided that the above copyright notice appear in all copies and
46 * that both that copyright notice and this permission notice appear
47 * in supporting documentation. Silicon Graphics makes no
48 * representations about the suitability of this software for any
49 * purpose. It is provided "as is" without express or implied warranty.
52 /** @file bits/stl_set.h
53 * This is an internal header file, included by other library headers.
54 * Do not attempt to use it directly. @headername{set}
60 #include <bits/concept_check.h>
61 #include <initializer_list>
63 _GLIBCXX_BEGIN_NESTED_NAMESPACE(std
, _GLIBCXX_STD_D
)
66 * @brief A standard container made up of unique keys, which can be
67 * retrieved in logarithmic time.
69 * @ingroup associative_containers
71 * Meets the requirements of a <a href="tables.html#65">container</a>, a
72 * <a href="tables.html#66">reversible container</a>, and an
73 * <a href="tables.html#69">associative container</a> (using unique keys).
75 * Sets support bidirectional iterators.
77 * @param Key Type of key objects.
78 * @param Compare Comparison function object type, defaults to less<Key>.
79 * @param Alloc Allocator type, defaults to allocator<Key>.
81 * The private tree data is declared exactly the same way for set and
82 * multiset; the distinction is made entirely in how the tree functions are
83 * called (*_unique versus *_equal, same as the standard).
85 template<typename _Key
, typename _Compare
= std::less
<_Key
>,
86 typename _Alloc
= std::allocator
<_Key
> >
89 // concept requirements
90 typedef typename
_Alloc::value_type _Alloc_value_type
;
91 __glibcxx_class_requires(_Key
, _SGIAssignableConcept
)
92 __glibcxx_class_requires4(_Compare
, bool, _Key
, _Key
,
93 _BinaryFunctionConcept
)
94 __glibcxx_class_requires2(_Key
, _Alloc_value_type
, _SameTypeConcept
)
100 typedef _Key key_type
;
101 typedef _Key value_type
;
102 typedef _Compare key_compare
;
103 typedef _Compare value_compare
;
104 typedef _Alloc allocator_type
;
108 typedef typename
_Alloc::template rebind
<_Key
>::other _Key_alloc_type
;
110 typedef _Rb_tree
<key_type
, value_type
, _Identity
<value_type
>,
111 key_compare
, _Key_alloc_type
> _Rep_type
;
112 _Rep_type _M_t
; // Red-black tree representing set.
116 /// Iterator-related typedefs.
117 typedef typename
_Key_alloc_type::pointer pointer
;
118 typedef typename
_Key_alloc_type::const_pointer const_pointer
;
119 typedef typename
_Key_alloc_type::reference reference
;
120 typedef typename
_Key_alloc_type::const_reference const_reference
;
121 // _GLIBCXX_RESOLVE_LIB_DEFECTS
122 // DR 103. set::iterator is required to be modifiable,
123 // but this allows modification of keys.
124 typedef typename
_Rep_type::const_iterator iterator
;
125 typedef typename
_Rep_type::const_iterator const_iterator
;
126 typedef typename
_Rep_type::const_reverse_iterator reverse_iterator
;
127 typedef typename
_Rep_type::const_reverse_iterator const_reverse_iterator
;
128 typedef typename
_Rep_type::size_type size_type
;
129 typedef typename
_Rep_type::difference_type difference_type
;
132 // allocation/deallocation
134 * @brief Default constructor creates no elements.
140 * @brief Creates a %set with no elements.
141 * @param comp Comparator to use.
142 * @param a An allocator object.
145 set(const _Compare
& __comp
,
146 const allocator_type
& __a
= allocator_type())
147 : _M_t(__comp
, __a
) { }
150 * @brief Builds a %set from a range.
151 * @param first An input iterator.
152 * @param last An input iterator.
154 * Create a %set consisting of copies of the elements from [first,last).
155 * This is linear in N if the range is already sorted, and NlogN
156 * otherwise (where N is distance(first,last)).
158 template<typename _InputIterator
>
159 set(_InputIterator __first
, _InputIterator __last
)
161 { _M_t
._M_insert_unique(__first
, __last
); }
164 * @brief Builds a %set from a range.
165 * @param first An input iterator.
166 * @param last An input iterator.
167 * @param comp A comparison functor.
168 * @param a An allocator object.
170 * Create a %set consisting of copies of the elements from [first,last).
171 * This is linear in N if the range is already sorted, and NlogN
172 * otherwise (where N is distance(first,last)).
174 template<typename _InputIterator
>
175 set(_InputIterator __first
, _InputIterator __last
,
176 const _Compare
& __comp
,
177 const allocator_type
& __a
= allocator_type())
179 { _M_t
._M_insert_unique(__first
, __last
); }
182 * @brief %Set copy constructor.
183 * @param x A %set of identical element and allocator types.
185 * The newly-created %set uses a copy of the allocation object used
191 #ifdef __GXX_EXPERIMENTAL_CXX0X__
193 * @brief %Set move constructor
194 * @param x A %set of identical element and allocator types.
196 * The newly-created %set contains the exact contents of @a x.
197 * The contents of @a x are a valid, but unspecified %set.
200 : _M_t(std::move(__x
._M_t
)) { }
203 * @brief Builds a %set from an initializer_list.
204 * @param l An initializer_list.
205 * @param comp A comparison functor.
206 * @param a An allocator object.
208 * Create a %set consisting of copies of the elements in the list.
209 * This is linear in N if the list is already sorted, and NlogN
210 * otherwise (where N is @a l.size()).
212 set(initializer_list
<value_type
> __l
,
213 const _Compare
& __comp
= _Compare(),
214 const allocator_type
& __a
= allocator_type())
216 { _M_t
._M_insert_unique(__l
.begin(), __l
.end()); }
220 * @brief %Set assignment operator.
221 * @param x A %set of identical element and allocator types.
223 * All the elements of @a x are copied, but unlike the copy constructor,
224 * the allocator object is not copied.
227 operator=(const set
& __x
)
233 #ifdef __GXX_EXPERIMENTAL_CXX0X__
235 * @brief %Set move assignment operator.
236 * @param x A %set of identical element and allocator types.
238 * The contents of @a x are moved into this %set (without copying).
239 * @a x is a valid, but unspecified %set.
252 * @brief %Set list assignment operator.
253 * @param l An initializer_list.
255 * This function fills a %set with copies of the elements in the
256 * initializer list @a l.
258 * Note that the assignment completely changes the %set and
259 * that the resulting %set's size is the same as the number
260 * of elements assigned. Old data may be lost.
263 operator=(initializer_list
<value_type
> __l
)
266 this->insert(__l
.begin(), __l
.end());
273 /// Returns the comparison object with which the %set was constructed.
276 { return _M_t
.key_comp(); }
277 /// Returns the comparison object with which the %set was constructed.
280 { return _M_t
.key_comp(); }
281 /// Returns the allocator object with which the %set was constructed.
283 get_allocator() const
284 { return _M_t
.get_allocator(); }
287 * Returns a read-only (constant) iterator that points to the first
288 * element in the %set. Iteration is done in ascending order according
293 { return _M_t
.begin(); }
296 * Returns a read-only (constant) iterator that points one past the last
297 * element in the %set. Iteration is done in ascending order according
302 { return _M_t
.end(); }
305 * Returns a read-only (constant) iterator that points to the last
306 * element in the %set. Iteration is done in descending order according
311 { return _M_t
.rbegin(); }
314 * Returns a read-only (constant) reverse iterator that points to the
315 * last pair in the %set. Iteration is done in descending order
316 * according to the keys.
320 { return _M_t
.rend(); }
322 #ifdef __GXX_EXPERIMENTAL_CXX0X__
324 * Returns a read-only (constant) iterator that points to the first
325 * element in the %set. Iteration is done in ascending order according
330 { return _M_t
.begin(); }
333 * Returns a read-only (constant) iterator that points one past the last
334 * element in the %set. Iteration is done in ascending order according
339 { return _M_t
.end(); }
342 * Returns a read-only (constant) iterator that points to the last
343 * element in the %set. Iteration is done in descending order according
348 { return _M_t
.rbegin(); }
351 * Returns a read-only (constant) reverse iterator that points to the
352 * last pair in the %set. Iteration is done in descending order
353 * according to the keys.
357 { return _M_t
.rend(); }
360 /// Returns true if the %set is empty.
363 { return _M_t
.empty(); }
365 /// Returns the size of the %set.
368 { return _M_t
.size(); }
370 /// Returns the maximum size of the %set.
373 { return _M_t
.max_size(); }
376 * @brief Swaps data with another %set.
377 * @param x A %set of the same element and allocator types.
379 * This exchanges the elements between two sets in constant time.
380 * (It is only swapping a pointer, an integer, and an instance of
381 * the @c Compare type (which itself is often stateless and empty), so it
382 * should be quite fast.)
383 * Note that the global std::swap() function is specialized such that
384 * std::swap(s1,s2) will feed to this function.
388 { _M_t
.swap(__x
._M_t
); }
392 * @brief Attempts to insert an element into the %set.
393 * @param x Element to be inserted.
394 * @return A pair, of which the first element is an iterator that points
395 * to the possibly inserted element, and the second is a bool
396 * that is true if the element was actually inserted.
398 * This function attempts to insert an element into the %set. A %set
399 * relies on unique keys and thus an element is only inserted if it is
400 * not already present in the %set.
402 * Insertion requires logarithmic time.
404 std::pair
<iterator
, bool>
405 insert(const value_type
& __x
)
407 std::pair
<typename
_Rep_type::iterator
, bool> __p
=
408 _M_t
._M_insert_unique(__x
);
409 return std::pair
<iterator
, bool>(__p
.first
, __p
.second
);
412 #ifdef __GXX_EXPERIMENTAL_CXX0X__
413 std::pair
<iterator
, bool>
414 insert(value_type
&& __x
)
416 std::pair
<typename
_Rep_type::iterator
, bool> __p
=
417 _M_t
._M_insert_unique(std::move(__x
));
418 return std::pair
<iterator
, bool>(__p
.first
, __p
.second
);
423 * @brief Attempts to insert an element into the %set.
424 * @param position An iterator that serves as a hint as to where the
425 * element should be inserted.
426 * @param x Element to be inserted.
427 * @return An iterator that points to the element with key of @a x (may
428 * or may not be the element passed in).
430 * This function is not concerned about whether the insertion took place,
431 * and thus does not return a boolean like the single-argument insert()
432 * does. Note that the first parameter is only a hint and can
433 * potentially improve the performance of the insertion process. A bad
434 * hint would cause no gains in efficiency.
436 * For more on @a hinting, see:
437 * http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html
439 * Insertion requires logarithmic time (if the hint is not taken).
442 insert(const_iterator __position
, const value_type
& __x
)
443 { return _M_t
._M_insert_unique_(__position
, __x
); }
445 #ifdef __GXX_EXPERIMENTAL_CXX0X__
447 insert(const_iterator __position
, value_type
&& __x
)
448 { return _M_t
._M_insert_unique_(__position
, std::move(__x
)); }
452 * @brief A template function that attempts to insert a range
454 * @param first Iterator pointing to the start of the range to be
456 * @param last Iterator pointing to the end of the range.
458 * Complexity similar to that of the range constructor.
460 template<typename _InputIterator
>
462 insert(_InputIterator __first
, _InputIterator __last
)
463 { _M_t
._M_insert_unique(__first
, __last
); }
465 #ifdef __GXX_EXPERIMENTAL_CXX0X__
467 * @brief Attempts to insert a list of elements into the %set.
468 * @param list A std::initializer_list<value_type> of elements
471 * Complexity similar to that of the range constructor.
474 insert(initializer_list
<value_type
> __l
)
475 { this->insert(__l
.begin(), __l
.end()); }
478 #ifdef __GXX_EXPERIMENTAL_CXX0X__
479 // _GLIBCXX_RESOLVE_LIB_DEFECTS
480 // DR 130. Associative erase should return an iterator.
482 * @brief Erases an element from a %set.
483 * @param position An iterator pointing to the element to be erased.
484 * @return An iterator pointing to the element immediately following
485 * @a position prior to the element being erased. If no such
486 * element exists, end() is returned.
488 * This function erases an element, pointed to by the given iterator,
489 * from a %set. Note that this function only erases the element, and
490 * that if the element is itself a pointer, the pointed-to memory is not
491 * touched in any way. Managing the pointer is the user's
495 erase(const_iterator __position
)
496 { return _M_t
.erase(__position
); }
499 * @brief Erases an element from a %set.
500 * @param position An iterator pointing to the element to be erased.
502 * This function erases an element, pointed to by the given iterator,
503 * from a %set. Note that this function only erases the element, and
504 * that if the element is itself a pointer, the pointed-to memory is not
505 * touched in any way. Managing the pointer is the user's
509 erase(iterator __position
)
510 { _M_t
.erase(__position
); }
514 * @brief Erases elements according to the provided key.
515 * @param x Key of element to be erased.
516 * @return The number of elements erased.
518 * This function erases all the elements located by the given key from
520 * Note that this function only erases the element, and that if
521 * the element is itself a pointer, the pointed-to memory is not touched
522 * in any way. Managing the pointer is the user's responsibility.
525 erase(const key_type
& __x
)
526 { return _M_t
.erase(__x
); }
528 #ifdef __GXX_EXPERIMENTAL_CXX0X__
529 // _GLIBCXX_RESOLVE_LIB_DEFECTS
530 // DR 130. Associative erase should return an iterator.
532 * @brief Erases a [first,last) range of elements from a %set.
533 * @param first Iterator pointing to the start of the range to be
535 * @param last Iterator pointing to the end of the range to be erased.
536 * @return The iterator @a last.
538 * This function erases a sequence of elements from a %set.
539 * Note that this function only erases the element, and that if
540 * the element is itself a pointer, the pointed-to memory is not touched
541 * in any way. Managing the pointer is the user's responsibility.
544 erase(const_iterator __first
, const_iterator __last
)
545 { return _M_t
.erase(__first
, __last
); }
548 * @brief Erases a [first,last) range of elements from a %set.
549 * @param first Iterator pointing to the start of the range to be
551 * @param last Iterator pointing to the end of the range to be erased.
553 * This function erases a sequence of elements from a %set.
554 * Note that this function only erases the element, and that if
555 * the element is itself a pointer, the pointed-to memory is not touched
556 * in any way. Managing the pointer is the user's responsibility.
559 erase(iterator __first
, iterator __last
)
560 { _M_t
.erase(__first
, __last
); }
564 * Erases all elements in a %set. Note that this function only erases
565 * the elements, and that if the elements themselves are pointers, the
566 * pointed-to memory is not touched in any way. Managing the pointer is
567 * the user's responsibility.
576 * @brief Finds the number of elements.
577 * @param x Element to located.
578 * @return Number of elements with specified key.
580 * This function only makes sense for multisets; for set the result will
581 * either be 0 (not present) or 1 (present).
584 count(const key_type
& __x
) const
585 { return _M_t
.find(__x
) == _M_t
.end() ? 0 : 1; }
587 // _GLIBCXX_RESOLVE_LIB_DEFECTS
588 // 214. set::find() missing const overload
591 * @brief Tries to locate an element in a %set.
592 * @param x Element to be located.
593 * @return Iterator pointing to sought-after element, or end() if not
596 * This function takes a key and tries to locate the element with which
597 * the key matches. If successful the function returns an iterator
598 * pointing to the sought after element. If unsuccessful it returns the
599 * past-the-end ( @c end() ) iterator.
602 find(const key_type
& __x
)
603 { return _M_t
.find(__x
); }
606 find(const key_type
& __x
) const
607 { return _M_t
.find(__x
); }
612 * @brief Finds the beginning of a subsequence matching given key.
613 * @param x Key to be located.
614 * @return Iterator pointing to first element equal to or greater
615 * than key, or end().
617 * This function returns the first element of a subsequence of elements
618 * that matches the given key. If unsuccessful it returns an iterator
619 * pointing to the first element that has a greater value than given key
620 * or end() if no such element exists.
623 lower_bound(const key_type
& __x
)
624 { return _M_t
.lower_bound(__x
); }
627 lower_bound(const key_type
& __x
) const
628 { return _M_t
.lower_bound(__x
); }
633 * @brief Finds the end of a subsequence matching given key.
634 * @param x Key to be located.
635 * @return Iterator pointing to the first element
636 * greater than key, or end().
639 upper_bound(const key_type
& __x
)
640 { return _M_t
.upper_bound(__x
); }
643 upper_bound(const key_type
& __x
) const
644 { return _M_t
.upper_bound(__x
); }
649 * @brief Finds a subsequence matching given key.
650 * @param x Key to be located.
651 * @return Pair of iterators that possibly points to the subsequence
652 * matching given key.
654 * This function is equivalent to
656 * std::make_pair(c.lower_bound(val),
657 * c.upper_bound(val))
659 * (but is faster than making the calls separately).
661 * This function probably only makes sense for multisets.
663 std::pair
<iterator
, iterator
>
664 equal_range(const key_type
& __x
)
665 { return _M_t
.equal_range(__x
); }
667 std::pair
<const_iterator
, const_iterator
>
668 equal_range(const key_type
& __x
) const
669 { return _M_t
.equal_range(__x
); }
672 template<typename _K1
, typename _C1
, typename _A1
>
674 operator==(const set
<_K1
, _C1
, _A1
>&, const set
<_K1
, _C1
, _A1
>&);
676 template<typename _K1
, typename _C1
, typename _A1
>
678 operator<(const set
<_K1
, _C1
, _A1
>&, const set
<_K1
, _C1
, _A1
>&);
683 * @brief Set equality comparison.
685 * @param y A %set of the same type as @a x.
686 * @return True iff the size and elements of the sets are equal.
688 * This is an equivalence relation. It is linear in the size of the sets.
689 * Sets are considered equivalent if their sizes are equal, and if
690 * corresponding elements compare equal.
692 template<typename _Key
, typename _Compare
, typename _Alloc
>
694 operator==(const set
<_Key
, _Compare
, _Alloc
>& __x
,
695 const set
<_Key
, _Compare
, _Alloc
>& __y
)
696 { return __x
._M_t
== __y
._M_t
; }
699 * @brief Set ordering relation.
701 * @param y A %set of the same type as @a x.
702 * @return True iff @a x is lexicographically less than @a y.
704 * This is a total ordering relation. It is linear in the size of the
705 * maps. The elements must be comparable with @c <.
707 * See std::lexicographical_compare() for how the determination is made.
709 template<typename _Key
, typename _Compare
, typename _Alloc
>
711 operator<(const set
<_Key
, _Compare
, _Alloc
>& __x
,
712 const set
<_Key
, _Compare
, _Alloc
>& __y
)
713 { return __x
._M_t
< __y
._M_t
; }
715 /// Returns !(x == y).
716 template<typename _Key
, typename _Compare
, typename _Alloc
>
718 operator!=(const set
<_Key
, _Compare
, _Alloc
>& __x
,
719 const set
<_Key
, _Compare
, _Alloc
>& __y
)
720 { return !(__x
== __y
); }
723 template<typename _Key
, typename _Compare
, typename _Alloc
>
725 operator>(const set
<_Key
, _Compare
, _Alloc
>& __x
,
726 const set
<_Key
, _Compare
, _Alloc
>& __y
)
727 { return __y
< __x
; }
730 template<typename _Key
, typename _Compare
, typename _Alloc
>
732 operator<=(const set
<_Key
, _Compare
, _Alloc
>& __x
,
733 const set
<_Key
, _Compare
, _Alloc
>& __y
)
734 { return !(__y
< __x
); }
737 template<typename _Key
, typename _Compare
, typename _Alloc
>
739 operator>=(const set
<_Key
, _Compare
, _Alloc
>& __x
,
740 const set
<_Key
, _Compare
, _Alloc
>& __y
)
741 { return !(__x
< __y
); }
743 /// See std::set::swap().
744 template<typename _Key
, typename _Compare
, typename _Alloc
>
746 swap(set
<_Key
, _Compare
, _Alloc
>& __x
, set
<_Key
, _Compare
, _Alloc
>& __y
)
749 _GLIBCXX_END_NESTED_NAMESPACE
751 #endif /* _STL_SET_H */