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// Set implementation -*- C++ -*-
// Copyright (C) 2001, 2002, 2004, 2005, 2006 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING. If not, write to the Free
// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
// USA.
// As a special exception, you may use this file as part of a free software
// library without restriction. Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License. This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.
/*
*
* Copyright (c) 1994
* Hewlett-Packard Company
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Hewlett-Packard Company makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*
*
* Copyright (c) 1996,1997
* Silicon Graphics Computer Systems, Inc.
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Silicon Graphics makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*/
/** @file stl_set.h
* This is an internal header file, included by other library headers.
* You should not attempt to use it directly.
*/
#ifndef _SET_H
#define _SET_H 1
#include <bits/concept_check.h>
_GLIBCXX_BEGIN_NESTED_NAMESPACE(std, _GLIBCXX_STD)
/**
* @brief A standard container made up of unique keys, which can be
* retrieved in logarithmic time.
*
* @ingroup Containers
* @ingroup Assoc_containers
*
* Meets the requirements of a <a href="tables.html#65">container</a>, a
* <a href="tables.html#66">reversible container</a>, and an
* <a href="tables.html#69">associative container</a> (using unique keys).
*
* Sets support bidirectional iterators.
*
* @param Key Type of key objects.
* @param Compare Comparison function object type, defaults to less<Key>.
* @param Alloc Allocator type, defaults to allocator<Key>.
*
* @if maint
* The private tree data is declared exactly the same way for set and
* multiset; the distinction is made entirely in how the tree functions are
* called (*_unique versus *_equal, same as the standard).
* @endif
*/
template<class _Key, class _Compare = std::less<_Key>,
class _Alloc = std::allocator<_Key> >
class set
{
// concept requirements
typedef typename _Alloc::value_type _Alloc_value_type;
__glibcxx_class_requires(_Key, _SGIAssignableConcept)
__glibcxx_class_requires4(_Compare, bool, _Key, _Key,
_BinaryFunctionConcept)
__glibcxx_class_requires2(_Key, _Alloc_value_type, _SameTypeConcept)
public:
// typedefs:
//@{
/// Public typedefs.
typedef _Key key_type;
typedef _Key value_type;
typedef _Compare key_compare;
typedef _Compare value_compare;
typedef _Alloc allocator_type;
//@}
private:
typedef typename _Alloc::template rebind<_Key>::other _Key_alloc_type;
typedef _Rb_tree<key_type, value_type, _Identity<value_type>,
key_compare, _Key_alloc_type> _Rep_type;
_Rep_type _M_t; // red-black tree representing set
public:
//@{
/// Iterator-related typedefs.
typedef typename _Key_alloc_type::pointer pointer;
typedef typename _Key_alloc_type::const_pointer const_pointer;
typedef typename _Key_alloc_type::reference reference;
typedef typename _Key_alloc_type::const_reference const_reference;
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// DR 103. set::iterator is required to be modifiable,
// but this allows modification of keys.
typedef typename _Rep_type::const_iterator iterator;
typedef typename _Rep_type::const_iterator const_iterator;
typedef typename _Rep_type::const_reverse_iterator reverse_iterator;
typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
typedef typename _Rep_type::size_type size_type;
typedef typename _Rep_type::difference_type difference_type;
//@}
// allocation/deallocation
/// Default constructor creates no elements.
set()
: _M_t(_Compare(), allocator_type()) {}
/**
* @brief Default constructor creates no elements.
*
* @param comp Comparator to use.
* @param a Allocator to use.
*/
explicit
set(const _Compare& __comp,
const allocator_type& __a = allocator_type())
: _M_t(__comp, __a) {}
/**
* @brief Builds a %set from a range.
* @param first An input iterator.
* @param last An input iterator.
*
* Create a %set consisting of copies of the elements from [first,last).
* This is linear in N if the range is already sorted, and NlogN
* otherwise (where N is distance(first,last)).
*/
template<class _InputIterator>
set(_InputIterator __first, _InputIterator __last)
: _M_t(_Compare(), allocator_type())
{ _M_t._M_insert_unique(__first, __last); }
/**
* @brief Builds a %set from a range.
* @param first An input iterator.
* @param last An input iterator.
* @param comp A comparison functor.
* @param a An allocator object.
*
* Create a %set consisting of copies of the elements from [first,last).
* This is linear in N if the range is already sorted, and NlogN
* otherwise (where N is distance(first,last)).
*/
template<class _InputIterator>
set(_InputIterator __first, _InputIterator __last,
const _Compare& __comp,
const allocator_type& __a = allocator_type())
: _M_t(__comp, __a)
{ _M_t._M_insert_unique(__first, __last); }
/**
* @brief Set copy constructor.
* @param x A %set of identical element and allocator types.
*
* The newly-created %set uses a copy of the allocation object used
* by @a x.
*/
set(const set<_Key,_Compare,_Alloc>& __x)
: _M_t(__x._M_t) { }
/**
* @brief Set assignment operator.
* @param x A %set of identical element and allocator types.
*
* All the elements of @a x are copied, but unlike the copy constructor,
* the allocator object is not copied.
*/
set<_Key,_Compare,_Alloc>&
operator=(const set<_Key, _Compare, _Alloc>& __x)
{
_M_t = __x._M_t;
return *this;
}
// accessors:
/// Returns the comparison object with which the %set was constructed.
key_compare
key_comp() const
{ return _M_t.key_comp(); }
/// Returns the comparison object with which the %set was constructed.
value_compare
value_comp() const
{ return _M_t.key_comp(); }
/// Returns the allocator object with which the %set was constructed.
allocator_type
get_allocator() const
{ return _M_t.get_allocator(); }
/**
* Returns a read/write iterator that points to the first element in the
* %set. Iteration is done in ascending order according to the keys.
*/
iterator
begin() const
{ return _M_t.begin(); }
/**
* Returns a read/write iterator that points one past the last element in
* the %set. Iteration is done in ascending order according to the keys.
*/
iterator
end() const
{ return _M_t.end(); }
/**
* Returns a read/write reverse iterator that points to the last element
* in the %set. Iteration is done in descending order according to the
* keys.
*/
reverse_iterator
rbegin() const
{ return _M_t.rbegin(); }
/**
* Returns a read-only (constant) reverse iterator that points to the
* last pair in the %map. Iteration is done in descending order
* according to the keys.
*/
reverse_iterator
rend() const
{ return _M_t.rend(); }
/// Returns true if the %set is empty.
bool
empty() const
{ return _M_t.empty(); }
/// Returns the size of the %set.
size_type
size() const
{ return _M_t.size(); }
/// Returns the maximum size of the %set.
size_type
max_size() const
{ return _M_t.max_size(); }
/**
* @brief Swaps data with another %set.
* @param x A %set of the same element and allocator types.
*
* This exchanges the elements between two sets in constant time.
* (It is only swapping a pointer, an integer, and an instance of
* the @c Compare type (which itself is often stateless and empty), so it
* should be quite fast.)
* Note that the global std::swap() function is specialized such that
* std::swap(s1,s2) will feed to this function.
*/
void
swap(set<_Key,_Compare,_Alloc>& __x)
{ _M_t.swap(__x._M_t); }
// insert/erase
/**
* @brief Attempts to insert an element into the %set.
* @param x Element to be inserted.
* @return A pair, of which the first element is an iterator that points
* to the possibly inserted element, and the second is a bool
* that is true if the element was actually inserted.
*
* This function attempts to insert an element into the %set. A %set
* relies on unique keys and thus an element is only inserted if it is
* not already present in the %set.
*
* Insertion requires logarithmic time.
*/
std::pair<iterator,bool>
insert(const value_type& __x)
{
std::pair<typename _Rep_type::iterator, bool> __p =
_M_t._M_insert_unique(__x);
return std::pair<iterator, bool>(__p.first, __p.second);
}
/**
* @brief Attempts to insert an element into the %set.
* @param position An iterator that serves as a hint as to where the
* element should be inserted.
* @param x Element to be inserted.
* @return An iterator that points to the element with key of @a x (may
* or may not be the element passed in).
*
* This function is not concerned about whether the insertion took place,
* and thus does not return a boolean like the single-argument insert()
* does. Note that the first parameter is only a hint and can
* potentially improve the performance of the insertion process. A bad
* hint would cause no gains in efficiency.
*
* See http://gcc.gnu.org/onlinedocs/libstdc++/23_containers/howto.html#4
* for more on "hinting".
*
* Insertion requires logarithmic time (if the hint is not taken).
*/
iterator
insert(iterator __position, const value_type& __x)
{ return _M_t._M_insert_unique(__position, __x); }
/**
* @brief A template function that attemps to insert a range of elements.
* @param first Iterator pointing to the start of the range to be
* inserted.
* @param last Iterator pointing to the end of the range.
*
* Complexity similar to that of the range constructor.
*/
template<class _InputIterator>
void
insert(_InputIterator __first, _InputIterator __last)
{ _M_t._M_insert_unique(__first, __last); }
/**
* @brief Erases an element from a %set.
* @param position An iterator pointing to the element to be erased.
*
* This function erases an element, pointed to by the given iterator,
* from a %set. Note that this function only erases the element, and
* that if the element is itself a pointer, the pointed-to memory is not
* touched in any way. Managing the pointer is the user's responsibilty.
*/
void
erase(iterator __position)
{ _M_t.erase(__position); }
/**
* @brief Erases elements according to the provided key.
* @param x Key of element to be erased.
* @return The number of elements erased.
*
* This function erases all the elements located by the given key from
* a %set.
* Note that this function only erases the element, and that if
* the element is itself a pointer, the pointed-to memory is not touched
* in any way. Managing the pointer is the user's responsibilty.
*/
size_type
erase(const key_type& __x)
{ return _M_t.erase(__x); }
/**
* @brief Erases a [first,last) range of elements from a %set.
* @param first Iterator pointing to the start of the range to be
* erased.
* @param last Iterator pointing to the end of the range to be erased.
*
* This function erases a sequence of elements from a %set.
* Note that this function only erases the element, and that if
* the element is itself a pointer, the pointed-to memory is not touched
* in any way. Managing the pointer is the user's responsibilty.
*/
void
erase(iterator __first, iterator __last)
{ _M_t.erase(__first, __last); }
/**
* Erases all elements in a %set. Note that this function only erases
* the elements, and that if the elements themselves are pointers, the
* pointed-to memory is not touched in any way. Managing the pointer is
* the user's responsibilty.
*/
void
clear()
{ _M_t.clear(); }
// set operations:
/**
* @brief Finds the number of elements.
* @param x Element to located.
* @return Number of elements with specified key.
*
* This function only makes sense for multisets; for set the result will
* either be 0 (not present) or 1 (present).
*/
size_type
count(const key_type& __x) const
{ return _M_t.find(__x) == _M_t.end() ? 0 : 1; }
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 214. set::find() missing const overload
//@{
/**
* @brief Tries to locate an element in a %set.
* @param x Element to be located.
* @return Iterator pointing to sought-after element, or end() if not
* found.
*
* This function takes a key and tries to locate the element with which
* the key matches. If successful the function returns an iterator
* pointing to the sought after element. If unsuccessful it returns the
* past-the-end ( @c end() ) iterator.
*/
iterator
find(const key_type& __x)
{ return _M_t.find(__x); }
const_iterator
find(const key_type& __x) const
{ return _M_t.find(__x); }
//@}
//@{
/**
* @brief Finds the beginning of a subsequence matching given key.
* @param x Key to be located.
* @return Iterator pointing to first element equal to or greater
* than key, or end().
*
* This function returns the first element of a subsequence of elements
* that matches the given key. If unsuccessful it returns an iterator
* pointing to the first element that has a greater value than given key
* or end() if no such element exists.
*/
iterator
lower_bound(const key_type& __x)
{ return _M_t.lower_bound(__x); }
const_iterator
lower_bound(const key_type& __x) const
{ return _M_t.lower_bound(__x); }
//@}
//@{
/**
* @brief Finds the end of a subsequence matching given key.
* @param x Key to be located.
* @return Iterator pointing to the first element
* greater than key, or end().
*/
iterator
upper_bound(const key_type& __x)
{ return _M_t.upper_bound(__x); }
const_iterator
upper_bound(const key_type& __x) const
{ return _M_t.upper_bound(__x); }
//@}
//@{
/**
* @brief Finds a subsequence matching given key.
* @param x Key to be located.
* @return Pair of iterators that possibly points to the subsequence
* matching given key.
*
* This function is equivalent to
* @code
* std::make_pair(c.lower_bound(val),
* c.upper_bound(val))
* @endcode
* (but is faster than making the calls separately).
*
* This function probably only makes sense for multisets.
*/
std::pair<iterator, iterator>
equal_range(const key_type& __x)
{ return _M_t.equal_range(__x); }
std::pair<const_iterator, const_iterator>
equal_range(const key_type& __x) const
{ return _M_t.equal_range(__x); }
//@}
template<class _K1, class _C1, class _A1>
friend bool
operator== (const set<_K1, _C1, _A1>&, const set<_K1, _C1, _A1>&);
template<class _K1, class _C1, class _A1>
friend bool
operator< (const set<_K1, _C1, _A1>&, const set<_K1, _C1, _A1>&);
};
/**
* @brief Set equality comparison.
* @param x A %set.
* @param y A %set of the same type as @a x.
* @return True iff the size and elements of the sets are equal.
*
* This is an equivalence relation. It is linear in the size of the sets.
* Sets are considered equivalent if their sizes are equal, and if
* corresponding elements compare equal.
*/
template<class _Key, class _Compare, class _Alloc>
inline bool
operator==(const set<_Key, _Compare, _Alloc>& __x,
const set<_Key, _Compare, _Alloc>& __y)
{ return __x._M_t == __y._M_t; }
/**
* @brief Set ordering relation.
* @param x A %set.
* @param y A %set of the same type as @a x.
* @return True iff @a x is lexicographically less than @a y.
*
* This is a total ordering relation. It is linear in the size of the
* maps. The elements must be comparable with @c <.
*
* See std::lexicographical_compare() for how the determination is made.
*/
template<class _Key, class _Compare, class _Alloc>
inline bool
operator<(const set<_Key, _Compare, _Alloc>& __x,
const set<_Key, _Compare, _Alloc>& __y)
{ return __x._M_t < __y._M_t; }
/// Returns !(x == y).
template<class _Key, class _Compare, class _Alloc>
inline bool
operator!=(const set<_Key, _Compare, _Alloc>& __x,
const set<_Key, _Compare, _Alloc>& __y)
{ return !(__x == __y); }
/// Returns y < x.
template<class _Key, class _Compare, class _Alloc>
inline bool
operator>(const set<_Key, _Compare, _Alloc>& __x,
const set<_Key, _Compare, _Alloc>& __y)
{ return __y < __x; }
/// Returns !(y < x)
template<class _Key, class _Compare, class _Alloc>
inline bool
operator<=(const set<_Key, _Compare, _Alloc>& __x,
const set<_Key, _Compare, _Alloc>& __y)
{ return !(__y < __x); }
/// Returns !(x < y)
template<class _Key, class _Compare, class _Alloc>
inline bool
operator>=(const set<_Key, _Compare, _Alloc>& __x,
const set<_Key, _Compare, _Alloc>& __y)
{ return !(__x < __y); }
/// See std::set::swap().
template<class _Key, class _Compare, class _Alloc>
inline void
swap(set<_Key, _Compare, _Alloc>& __x, set<_Key, _Compare, _Alloc>& __y)
{ __x.swap(__y); }
_GLIBCXX_END_NESTED_NAMESPACE
#endif /* _SET_H */
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