std::set< Key, Compare, Alloc > Class Template Reference
[Containers, Associative Containers]

A standard container made up of unique keys, which can be retrieved in logarithmic time. More...

#include <stl_set.h>

Inheritance diagram for std::set< Key, Compare, Alloc >:

[legend]Collaboration diagram for std::set< Key, Compare, Alloc >:

[legend]List of all members.

Public Types
typedef Key	key_type
	Public typedefs.
typedef Key	value_type
	Public typedefs.
typedef Compare	key_compare
	Public typedefs.
typedef Compare	value_compare
	Public typedefs.
typedef Alloc::pointer	pointer
	Iterator-related typedefs.
typedef Alloc::const_pointer	const_pointer
	Iterator-related typedefs.
typedef Alloc::reference	reference
	Iterator-related typedefs.
typedef Alloc::const_reference	const_reference
	Iterator-related typedefs.
typedef Rep_type::const_iterator	iterator
	Iterator-related typedefs.
typedef Rep_type::const_iterator	const_iterator
	Iterator-related typedefs.
typedef Rep_type::const_reverse_iterator	reverse_iterator
	Iterator-related typedefs.
typedef Rep_type::const_reverse_iterator	const_reverse_iterator
	Iterator-related typedefs.
typedef Rep_type::size_type	size_type
	Iterator-related typedefs.
typedef Rep_type::difference_type	difference_type
	Iterator-related typedefs.
typedef Rep_type::allocator_type	allocator_type
	Iterator-related typedefs.
Public Member Functions
	set ()
	Default constructor creates no elements.
	set (const Compare &comp, const allocator_type &a=allocator_type())
	Default constructor creates no elements.
template<class InputIterator>
	set (InputIterator first, InputIterator last)
	Builds a set from a range.
template<class InputIterator>
	set (InputIterator first, InputIterator last, const Compare &comp, const allocator_type &a=allocator_type())
	Builds a set from a range.
	set (const set< Key, Compare, Alloc > &x)
	Set copy constructor.
set< Key, Compare, Alloc > &	operator= (const set< Key, Compare, Alloc > &x)
	Set assignment operator.
key_compare	key_comp () const
	Returns the comparison object with which the set was constructed.
value_compare	value_comp () const
	Returns the comparison object with which the set was constructed.
allocator_type	get_allocator () const
	Returns the allocator object with which the set was constructed.
iterator	begin () const
iterator	end () const
reverse_iterator	rbegin () const
reverse_iterator	rend () const
bool	empty () const
	Returns true if the set is empty.
size_type	size () const
	Returns the size of the set.
size_type	max_size () const
	Returns the maximum size of the set.
void	swap (set< Key, Compare, Alloc > &x)
	Swaps data with another set.
pair< iterator, bool >	insert (const value_type &x)
	Attempts to insert an element into the set.
iterator	insert (iterator position, const value_type &x)
	Attempts to insert an element into the set.
template<class InputIterator>
void	insert (InputIterator first, InputIterator last)
	A template function that attemps to insert a range of elements.
void	erase (iterator position)
	Erases an element from a set.
size_type	erase (const key_type &x)
	Erases elements according to the provided key.
void	erase (iterator first, iterator last)
	Erases a [first,last) range of elements from a set.
void	clear ()
size_type	count (const key_type &x) const
	Finds the number of elements.
iterator	find (const key_type &x)
	Tries to locate an element in a set.
const_iterator	find (const key_type &x) const
	Tries to locate an element in a set.
iterator	lower_bound (const key_type &x)
	Finds the beginning of a subsequence matching given key.
const_iterator	lower_bound (const key_type &x) const
	Finds the beginning of a subsequence matching given key.
iterator	upper_bound (const key_type &x)
	Finds the end of a subsequence matching given key.
const_iterator	upper_bound (const key_type &x) const
	Finds the end of a subsequence matching given key.
pair< iterator, iterator >	equal_range (const key_type &x)
	Finds a subsequence matching given key.
pair< const_iterator, const_iterator >	equal_range (const key_type &x) const
	Finds a subsequence matching given key.
Private Types
typedef Rb_tree< key_type, value_type, Identity< value_type >, key_compare, Alloc >	Rep_type
Private Attributes
Rep_type	M_t

---

Detailed Description

template<class Key, class Compare, class Alloc>
class std::set< Key, Compare, Alloc >

A standard container made up of unique keys, which can be retrieved in logarithmic time.

Meets the requirements of a container, a reversible container, and an associative container (using unique keys).

Sets support bidirectional iterators.

Parameters:

	Key	Type of key objects.
	Compare	Comparison function object type, defaults to less<Key>.
	Alloc	Allocator type, defaults to allocator<Key>.

Definition at line 107 of file stl_set.h.

---

Member Typedef Documentation

template<class Key, class Compare, class Alloc>

typedef Key std::set< Key, Compare, Alloc >::key_type

Public typedefs.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 118 of file stl_set.h.

template<class Key, class Compare, class Alloc>

typedef Key std::set< Key, Compare, Alloc >::value_type

Public typedefs.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 119 of file stl_set.h.

template<class Key, class Compare, class Alloc>

typedef Compare std::set< Key, Compare, Alloc >::key_compare

Public typedefs.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 120 of file stl_set.h.

template<class Key, class Compare, class Alloc>

typedef Compare std::set< Key, Compare, Alloc >::value_compare

Public typedefs.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 121 of file stl_set.h.

template<class Key, class Compare, class Alloc>

typedef Alloc::pointer std::set< Key, Compare, Alloc >::pointer

Iterator-related typedefs.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 131 of file stl_set.h.

template<class Key, class Compare, class Alloc>

typedef Alloc::const_pointer std::set< Key, Compare, Alloc >::const_pointer

Iterator-related typedefs.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 132 of file stl_set.h.

template<class Key, class Compare, class Alloc>

typedef Alloc::reference std::set< Key, Compare, Alloc >::reference

Iterator-related typedefs.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 133 of file stl_set.h.

template<class Key, class Compare, class Alloc>

typedef Alloc::const_reference std::set< Key, Compare, Alloc >::const_reference

Iterator-related typedefs.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 134 of file stl_set.h.

template<class Key, class Compare, class Alloc>

typedef Rep_type::const_iterator std::set< Key, Compare, Alloc >::iterator

Iterator-related typedefs.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 138 of file stl_set.h.

template<class Key, class Compare, class Alloc>

typedef Rep_type::const_iterator std::set< Key, Compare, Alloc >::const_iterator

Iterator-related typedefs.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 139 of file stl_set.h.

template<class Key, class Compare, class Alloc>

typedef Rep_type::const_reverse_iterator std::set< Key, Compare, Alloc >::reverse_iterator

Iterator-related typedefs.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 140 of file stl_set.h.

template<class Key, class Compare, class Alloc>

typedef Rep_type::const_reverse_iterator std::set< Key, Compare, Alloc >::const_reverse_iterator

Iterator-related typedefs.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 141 of file stl_set.h.

template<class Key, class Compare, class Alloc>

typedef Rep_type::size_type std::set< Key, Compare, Alloc >::size_type

Iterator-related typedefs.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 142 of file stl_set.h.

template<class Key, class Compare, class Alloc>

typedef Rep_type::difference_type std::set< Key, Compare, Alloc >::difference_type

Iterator-related typedefs.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 143 of file stl_set.h.

template<class Key, class Compare, class Alloc>

typedef Rep_type::allocator_type std::set< Key, Compare, Alloc >::allocator_type

Iterator-related typedefs.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 144 of file stl_set.h.

---

Constructor & Destructor Documentation

template<class Key, class Compare, class Alloc>

std::set< Key, Compare, Alloc >::set

(

)

[inline]

Default constructor creates no elements.

Definition at line 149 of file stl_set.h.

template<class Key, class Compare, class Alloc>

std::set< Key, Compare, Alloc >::set	(	const Compare &	comp,
		const allocator_type &	a = allocator_type()
	)			[inline, explicit]

Default constructor creates no elements.

Parameters:

	comp	Comparator to use.
	a	Allocator to use.

Definition at line 158 of file stl_set.h.

template<class Key, class Compare, class Alloc>

template<class InputIterator>

std::set< Key, Compare, Alloc >::set	(	InputIterator	first,
		InputIterator	last
	)			[inline]

Builds a set from a range.

Parameters:

	first	An input iterator.
	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)).

Definition at line 172 of file stl_set.h.

template<class Key, class Compare, class Alloc>

template<class InputIterator>

std::set< Key, Compare, Alloc >::set	(	InputIterator	first,
		InputIterator	last,
		const Compare &	comp,
		const allocator_type &	a = allocator_type()
	)			[inline]

Builds a set from a range.

Parameters:

	first	An input iterator.
	last	An input iterator.
	comp	A comparison functor.
	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)).

Definition at line 188 of file stl_set.h.

template<class Key, class Compare, class Alloc>

std::set< Key, Compare, Alloc >::set

(

const set< Key, Compare, Alloc > &

x

)

[inline]

Set copy constructor.

Parameters:

x

A set of identical element and allocator types.

The newly-created set uses a copy of the allocation object used by x.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 201 of file stl_set.h.

---

Member Function Documentation

template<class Key, class Compare, class Alloc>

set<Key,Compare,Alloc>& std::set< Key, Compare, Alloc >::operator=

(

const set< Key, Compare, Alloc > &

x

)

[inline]

Set assignment operator.

Parameters:

x

A set of identical element and allocator types.

All the elements of x are copied, but unlike the copy constructor, the allocator object is not copied.

Definition at line 212 of file stl_set.h.

template<class Key, class Compare, class Alloc>

key_compare std::set< Key, Compare, Alloc >::key_comp

(

)

const [inline]

Returns the comparison object with which the set was constructed.

Definition at line 222 of file stl_set.h.

Referenced by std::set< Key, Compare, Allocator >::key_comp().

template<class Key, class Compare, class Alloc>

value_compare std::set< Key, Compare, Alloc >::value_comp

(

)

const [inline]

Returns the comparison object with which the set was constructed.

Definition at line 226 of file stl_set.h.

template<class Key, class Compare, class Alloc>

allocator_type std::set< Key, Compare, Alloc >::get_allocator

(

)

const [inline]

Returns the allocator object with which the set was constructed.

Definition at line 230 of file stl_set.h.

template<class Key, class Compare, class Alloc>

iterator std::set< Key, Compare, Alloc >::begin

(

)

const [inline]

Returns a read/write iterator that points to the first element in the set. Iteration is done in ascending order according to the keys.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 238 of file stl_set.h.

template<class Key, class Compare, class Alloc>

iterator std::set< Key, Compare, Alloc >::end

(

)

const [inline]

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.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 246 of file stl_set.h.

template<class Key, class Compare, class Alloc>

reverse_iterator std::set< Key, Compare, Alloc >::rbegin

(

)

const [inline]

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.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 255 of file stl_set.h.

template<class Key, class Compare, class Alloc>

reverse_iterator std::set< Key, Compare, Alloc >::rend

(

)

const [inline]

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.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 264 of file stl_set.h.

template<class Key, class Compare, class Alloc>

bool std::set< Key, Compare, Alloc >::empty

(

)

const [inline]

Returns true if the set is empty.

Definition at line 269 of file stl_set.h.

template<class Key, class Compare, class Alloc>

size_type std::set< Key, Compare, Alloc >::size

(

)

const [inline]

Returns the size of the set.

Definition at line 274 of file stl_set.h.

template<class Key, class Compare, class Alloc>

size_type std::set< Key, Compare, Alloc >::max_size

(

)

const [inline]

Returns the maximum size of the set.

Definition at line 279 of file stl_set.h.

template<class Key, class Compare, class Alloc>

void std::set< Key, Compare, Alloc >::swap

(

set< Key, Compare, Alloc > &

x

)

[inline]

Swaps data with another set.

Parameters:

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 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.

Definition at line 294 of file stl_set.h.

Referenced by std::swap().

template<class Key, class Compare, class Alloc>

pair<iterator,bool> std::set< Key, Compare, Alloc >::insert

(

const value_type &

x

)

[inline]

Attempts to insert an element into the set.

Parameters:

x

Element to be inserted.

Returns:

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.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 312 of file stl_set.h.

template<class Key, class Compare, class Alloc>

iterator std::set< Key, Compare, Alloc >::insert	(	iterator	position,
		const value_type &	x
	)			[inline]

Attempts to insert an element into the set.

Parameters:

	position	An iterator that serves as a hint as to where the element should be inserted.
	x	Element to be inserted.

Returns:

An iterator that points to the element with key of 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).

Definition at line 338 of file stl_set.h.

template<class Key, class Compare, class Alloc>

template<class InputIterator>

void std::set< Key, Compare, Alloc >::insert	(	InputIterator	first,
		InputIterator	last
	)			[inline]

A template function that attemps to insert a range of elements.

Parameters:

	first	Iterator pointing to the start of the range to be inserted.
	last	Iterator pointing to the end of the range.

Complexity similar to that of the range constructor.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 354 of file stl_set.h.

template<class Key, class Compare, class Alloc>

void std::set< Key, Compare, Alloc >::erase

(

iterator

position

)

[inline]

Erases an element from a set.

Parameters:

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.

Definition at line 367 of file stl_set.h.

template<class Key, class Compare, class Alloc>

size_type std::set< Key, Compare, Alloc >::erase

(

const key_type &

x

)

[inline]

Erases elements according to the provided key.

Parameters:

x

Key of element to be erased.

Returns:

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.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 385 of file stl_set.h.

template<class Key, class Compare, class Alloc>

void std::set< Key, Compare, Alloc >::erase	(	iterator	first,
		iterator	last
	)			[inline]

Erases a [first,last) range of elements from a set.

Parameters:

	first	Iterator pointing to the start of the range to be erased.
	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.

Definition at line 399 of file stl_set.h.

template<class Key, class Compare, class Alloc>

void std::set< Key, Compare, Alloc >::clear

(

)

[inline]

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.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 412 of file stl_set.h.

template<class Key, class Compare, class Alloc>

size_type std::set< Key, Compare, Alloc >::count

(

const key_type &

x

)

const [inline]

Finds the number of elements.

Parameters:

x

Element to located.

Returns:

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).

Definition at line 426 of file stl_set.h.

template<class Key, class Compare, class Alloc>

iterator std::set< Key, Compare, Alloc >::find

(

const key_type &

x

)

[inline]

Tries to locate an element in a set.

Parameters:

x

Element to be located.

Returns:

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 ( end() ) iterator.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 444 of file stl_set.h.

template<class Key, class Compare, class Alloc>

const_iterator std::set< Key, Compare, Alloc >::find

(

const key_type &

x

)

const [inline]

Tries to locate an element in a set.

Parameters:

x

Element to be located.

Returns:

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 ( end() ) iterator.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 448 of file stl_set.h.

template<class Key, class Compare, class Alloc>

iterator std::set< Key, Compare, Alloc >::lower_bound

(

const key_type &

x

)

[inline]

Finds the beginning of a subsequence matching given key.

Parameters:

x

Key to be located.

Returns:

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.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 465 of file stl_set.h.

template<class Key, class Compare, class Alloc>

const_iterator std::set< Key, Compare, Alloc >::lower_bound

(

const key_type &

x

)

const [inline]

Finds the beginning of a subsequence matching given key.

Parameters:

x

Key to be located.

Returns:

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.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 469 of file stl_set.h.

template<class Key, class Compare, class Alloc>

iterator std::set< Key, Compare, Alloc >::upper_bound

(

const key_type &

x

)

[inline]

Finds the end of a subsequence matching given key.

Parameters:

x

Key to be located.

Returns:

Iterator pointing to the first element greater than key, or end().

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 481 of file stl_set.h.

template<class Key, class Compare, class Alloc>

const_iterator std::set< Key, Compare, Alloc >::upper_bound

(

const key_type &

x

)

const [inline]

Finds the end of a subsequence matching given key.

Parameters:

x

Key to be located.

Returns:

Iterator pointing to the first element greater than key, or end().

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 485 of file stl_set.h.

template<class Key, class Compare, class Alloc>

pair<iterator,iterator> std::set< Key, Compare, Alloc >::equal_range

(

const key_type &

x

)

[inline]

Finds a subsequence matching given key.

Parameters:

x

Key to be located.

Returns:

Pair of iterators that possibly points to the subsequence matching given key.

This function is equivalent to

    std::make_pair(c.lower_bound(val),
                   c.upper_bound(val))

(but is faster than making the calls separately).

This function probably only makes sense for multisets.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 506 of file stl_set.h.

template<class Key, class Compare, class Alloc>

pair<const_iterator,const_iterator> std::set< Key, Compare, Alloc >::equal_range

(

const key_type &

x

)

const [inline]

Finds a subsequence matching given key.

Parameters:

x

Key to be located.

Returns:

Pair of iterators that possibly points to the subsequence matching given key.

This function is equivalent to

    std::make_pair(c.lower_bound(val),
                   c.upper_bound(val))

(but is faster than making the calls separately).

This function probably only makes sense for multisets.

Reimplemented in __gnu_debug_def::set< Key, Compare, Allocator >.

Definition at line 510 of file stl_set.h.

---

The documentation for this class was generated from the following file:

• stl_set.h

---