libstdc++
std::unordered_set< _Value, _Hash, _Pred, _Alloc > Class Template Reference

Public Types

using insert_return_type = typename _Hashtable::insert_return_type
 
using node_type = typename _Hashtable::node_type
 
typedef _Hashtable::key_type key_type
 
typedef _Hashtable::value_type value_type
 
typedef _Hashtable::hasher hasher
 
typedef _Hashtable::key_equal key_equal
 
typedef _Hashtable::allocator_type allocator_type
 
typedef _Hashtable::pointer pointer
 
typedef _Hashtable::const_pointer const_pointer
 
typedef _Hashtable::reference reference
 
typedef _Hashtable::const_reference const_reference
 
typedef _Hashtable::iterator iterator
 
typedef _Hashtable::const_iterator const_iterator
 
typedef _Hashtable::local_iterator local_iterator
 
typedef _Hashtable::const_local_iterator const_local_iterator
 
typedef _Hashtable::size_type size_type
 
typedef _Hashtable::difference_type difference_type
 

Public Member Functions

 unordered_set ()=default
 
template<typename _InputIterator >
 unordered_set (_InputIterator __first, _InputIterator __last, size_type __n, const allocator_type &__a)
 
template<typename _InputIterator >
 unordered_set (_InputIterator __first, _InputIterator __last, size_type __n, const hasher &__hf, const allocator_type &__a)
 
template<typename _InputIterator >
 unordered_set (_InputIterator __first, _InputIterator __last, size_type __n=0, const hasher &__hf=hasher(), const key_equal &__eql=key_equal(), const allocator_type &__a=allocator_type())
 
 unordered_set (const allocator_type &__a)
 
 unordered_set (const unordered_set &)=default
 
 unordered_set (const unordered_set &__uset, const allocator_type &__a)
 
 unordered_set (initializer_list< value_type > __l, size_type __n, const allocator_type &__a)
 
 unordered_set (initializer_list< value_type > __l, size_type __n, const hasher &__hf, const allocator_type &__a)
 
 unordered_set (initializer_list< value_type > __l, size_type __n=0, const hasher &__hf=hasher(), const key_equal &__eql=key_equal(), const allocator_type &__a=allocator_type())
 
 unordered_set (size_type __n, const allocator_type &__a)
 
 unordered_set (size_type __n, const hasher &__hf, const allocator_type &__a)
 
 unordered_set (size_type __n, const hasher &__hf=hasher(), const key_equal &__eql=key_equal(), const allocator_type &__a=allocator_type())
 
 unordered_set (unordered_set &&)=default
 
 unordered_set (unordered_set &&__uset, const allocator_type &__a) noexcept(noexcept(_Hashtable(std::move(__uset._M_h), __a)))
 
size_type bucket (const key_type &__key) const
 
size_type bucket_count () const noexcept
 
size_type bucket_size (size_type __n) const
 
const_iterator cbegin () const noexcept
 
const_iterator cend () const noexcept
 
void clear () noexcept
 
template<typename... _Args>
std::pair< iterator, bool > emplace (_Args &&... __args)
 
template<typename... _Args>
iterator emplace_hint (const_iterator __pos, _Args &&... __args)
 
bool empty () const noexcept
 
size_type erase (const key_type &__x)
 
iterator erase (const_iterator __first, const_iterator __last)
 
node_type extract (const key_type &__key)
 
node_type extract (const_iterator __pos)
 
allocator_type get_allocator () const noexcept
 
hasher hash_function () const
 
template<typename _InputIterator >
void insert (_InputIterator __first, _InputIterator __last)
 
iterator insert (const_iterator, node_type &&__nh)
 
void insert (initializer_list< value_type > __l)
 
insert_return_type insert (node_type &&__nh)
 
key_equal key_eq () const
 
float load_factor () const noexcept
 
size_type max_bucket_count () const noexcept
 
float max_load_factor () const noexcept
 
void max_load_factor (float __z)
 
size_type max_size () const noexcept
 
template<typename _H2 , typename _P2 >
void merge (unordered_multiset< _Value, _H2, _P2, _Alloc > &&__source)
 
template<typename _H2 , typename _P2 >
void merge (unordered_multiset< _Value, _H2, _P2, _Alloc > &__source)
 
template<typename _H2 , typename _P2 >
void merge (unordered_set< _Value, _H2, _P2, _Alloc > &&__source)
 
template<typename _H2 , typename _P2 >
void merge (unordered_set< _Value, _H2, _P2, _Alloc > &__source)
 
unordered_setoperator= (const unordered_set &)=default
 
unordered_setoperator= (initializer_list< value_type > __l)
 
unordered_setoperator= (unordered_set &&)=default
 
void rehash (size_type __n)
 
void reserve (size_type __n)
 
size_type size () const noexcept
 
void swap (unordered_set &__x) noexcept(noexcept(_M_h.swap(__x._M_h)))
 
iterator begin () noexcept
 
const_iterator begin () const noexcept
 
iterator end () noexcept
 
const_iterator end () const noexcept
 
std::pair< iterator, bool > insert (const value_type &__x)
 
std::pair< iterator, bool > insert (value_type &&__x)
 
iterator insert (const_iterator __hint, const value_type &__x)
 
iterator insert (const_iterator __hint, value_type &&__x)
 
iterator erase (const_iterator __position)
 
iterator erase (iterator __position)
 
iterator find (const key_type &__x)
 
const_iterator find (const key_type &__x) const
 
size_type count (const key_type &__x) const
 
std::pair< iterator, iteratorequal_range (const key_type &__x)
 
std::pair< const_iterator, const_iteratorequal_range (const key_type &__x) const
 
local_iterator begin (size_type __n)
 
const_local_iterator begin (size_type __n) const
 
const_local_iterator cbegin (size_type __n) const
 
local_iterator end (size_type __n)
 
const_local_iterator end (size_type __n) const
 
const_local_iterator cend (size_type __n) const
 

Friends

template<typename _Value1 , typename _Hash1 , typename _Pred1 , typename _Alloc1 >
bool operator== (const unordered_set< _Value1, _Hash1, _Pred1, _Alloc1 > &, const unordered_set< _Value1, _Hash1, _Pred1, _Alloc1 > &)
 
template<typename , typename , typename >
class std::_Hash_merge_helper
 

Detailed Description

template<typename _Value, typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
class std::unordered_set< _Value, _Hash, _Pred, _Alloc >

A standard container composed of unique keys (containing at most one of each key value) in which the elements' keys are the elements themselves.

Template Parameters
_ValueType of key objects.
_HashHashing function object type, defaults to hash<_Value>.
_PredPredicate function object type, defaults to equal_to<_Value>.
_AllocAllocator type, defaults to allocator<_Key>.

Meets the requirements of a container, and unordered associative container

Base is _Hashtable, dispatched at compile time via template alias __uset_hashtable.

Definition at line 97 of file unordered_set.h.

Member Typedef Documentation

◆ allocator_type

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
typedef _Hashtable::allocator_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::allocator_type

Public typedefs.

Definition at line 110 of file unordered_set.h.

◆ const_iterator

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
typedef _Hashtable::const_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::const_iterator

Iterator-related typedefs.

Definition at line 120 of file unordered_set.h.

◆ const_local_iterator

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
typedef _Hashtable::const_local_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::const_local_iterator

Iterator-related typedefs.

Definition at line 122 of file unordered_set.h.

◆ const_pointer

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
typedef _Hashtable::const_pointer std::unordered_set< _Value, _Hash, _Pred, _Alloc >::const_pointer

Iterator-related typedefs.

Definition at line 116 of file unordered_set.h.

◆ const_reference

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
typedef _Hashtable::const_reference std::unordered_set< _Value, _Hash, _Pred, _Alloc >::const_reference

Iterator-related typedefs.

Definition at line 118 of file unordered_set.h.

◆ difference_type

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
typedef _Hashtable::difference_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::difference_type

Iterator-related typedefs.

Definition at line 124 of file unordered_set.h.

◆ hasher

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
typedef _Hashtable::hasher std::unordered_set< _Value, _Hash, _Pred, _Alloc >::hasher

Public typedefs.

Definition at line 108 of file unordered_set.h.

◆ iterator

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
typedef _Hashtable::iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::iterator

Iterator-related typedefs.

Definition at line 119 of file unordered_set.h.

◆ key_equal

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
typedef _Hashtable::key_equal std::unordered_set< _Value, _Hash, _Pred, _Alloc >::key_equal

Public typedefs.

Definition at line 109 of file unordered_set.h.

◆ key_type

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
typedef _Hashtable::key_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::key_type

Public typedefs.

Definition at line 106 of file unordered_set.h.

◆ local_iterator

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
typedef _Hashtable::local_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::local_iterator

Iterator-related typedefs.

Definition at line 121 of file unordered_set.h.

◆ pointer

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
typedef _Hashtable::pointer std::unordered_set< _Value, _Hash, _Pred, _Alloc >::pointer

Iterator-related typedefs.

Definition at line 115 of file unordered_set.h.

◆ reference

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
typedef _Hashtable::reference std::unordered_set< _Value, _Hash, _Pred, _Alloc >::reference

Iterator-related typedefs.

Definition at line 117 of file unordered_set.h.

◆ size_type

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
typedef _Hashtable::size_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::size_type

Iterator-related typedefs.

Definition at line 123 of file unordered_set.h.

◆ value_type

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
typedef _Hashtable::value_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::value_type

Public typedefs.

Definition at line 107 of file unordered_set.h.

Constructor & Destructor Documentation

◆ unordered_set() [1/7]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
std::unordered_set< _Value, _Hash, _Pred, _Alloc >::unordered_set ( )
default

Default constructor.

◆ unordered_set() [2/7]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
std::unordered_set< _Value, _Hash, _Pred, _Alloc >::unordered_set ( size_type  __n,
const hasher __hf = hasher(),
const key_equal __eql = key_equal(),
const allocator_type __a = allocator_type() 
)
inlineexplicit

Default constructor creates no elements.

Parameters
__nMinimal initial number of buckets.
__hfA hash functor.
__eqlA key equality functor.
__aAn allocator object.

Definition at line 145 of file unordered_set.h.

◆ unordered_set() [3/7]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
template<typename _InputIterator >
std::unordered_set< _Value, _Hash, _Pred, _Alloc >::unordered_set ( _InputIterator  __first,
_InputIterator  __last,
size_type  __n = 0,
const hasher __hf = hasher(),
const key_equal __eql = key_equal(),
const allocator_type __a = allocator_type() 
)
inline

Builds an unordered_set from a range.

Parameters
__firstAn input iterator.
__lastAn input iterator.
__nMinimal initial number of buckets.
__hfA hash functor.
__eqlA key equality functor.
__aAn allocator object.

Create an unordered_set consisting of copies of the elements from [__first,__last). This is linear in N (where N is distance(__first,__last)).

Definition at line 166 of file unordered_set.h.

◆ unordered_set() [4/7]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
std::unordered_set< _Value, _Hash, _Pred, _Alloc >::unordered_set ( const unordered_set< _Value, _Hash, _Pred, _Alloc > &  )
default

Copy constructor.

◆ unordered_set() [5/7]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
std::unordered_set< _Value, _Hash, _Pred, _Alloc >::unordered_set ( unordered_set< _Value, _Hash, _Pred, _Alloc > &&  )
default

Move constructor.

◆ unordered_set() [6/7]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
std::unordered_set< _Value, _Hash, _Pred, _Alloc >::unordered_set ( const allocator_type __a)
inlineexplicit

Creates an unordered_set with no elements.

Parameters
__aAn allocator object.

Definition at line 185 of file unordered_set.h.

◆ unordered_set() [7/7]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
std::unordered_set< _Value, _Hash, _Pred, _Alloc >::unordered_set ( initializer_list< value_type __l,
size_type  __n = 0,
const hasher __hf = hasher(),
const key_equal __eql = key_equal(),
const allocator_type __a = allocator_type() 
)
inline

Builds an unordered_set from an initializer_list.

Parameters
__lAn initializer_list.
__nMinimal initial number of buckets.
__hfA hash functor.
__eqlA key equality functor.
__aAn allocator object.

Create an unordered_set consisting of copies of the elements in the list. This is linear in N (where N is __l.size()).

Definition at line 221 of file unordered_set.h.

Member Function Documentation

◆ begin() [1/4]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
const_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::begin ( ) const
inlinenoexcept

Returns a read-only (constant) iterator that points to the first element in the unordered_set.

Definition at line 324 of file unordered_set.h.

◆ begin() [2/4]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::begin ( )
inlinenoexcept

Returns a read-only (constant) iterator that points to the first element in the unordered_set.

Definition at line 320 of file unordered_set.h.

◆ begin() [3/4]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
local_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::begin ( size_type  __n)
inline

Returns a read-only (constant) iterator pointing to the first bucket element.

Parameters
__nThe bucket index.
Returns
A read-only local iterator.

Definition at line 788 of file unordered_set.h.

◆ begin() [4/4]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
const_local_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::begin ( size_type  __n) const
inline

Returns a read-only (constant) iterator pointing to the first bucket element.

Parameters
__nThe bucket index.
Returns
A read-only local iterator.

Definition at line 792 of file unordered_set.h.

◆ bucket_count()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
size_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::bucket_count ( ) const
inlinenoexcept

Returns the number of buckets of the unordered_set.

Definition at line 754 of file unordered_set.h.

◆ cbegin() [1/2]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
const_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::cbegin ( ) const
inlinenoexcept

Returns a read-only (constant) iterator that points to the first element in the unordered_set.

Definition at line 347 of file unordered_set.h.

◆ cbegin() [2/2]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
const_local_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::cbegin ( size_type  __n) const
inline

Returns a read-only (constant) iterator pointing to the first bucket element.

Parameters
__nThe bucket index.
Returns
A read-only local iterator.

Definition at line 796 of file unordered_set.h.

◆ cend() [1/2]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
const_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::cend ( ) const
inlinenoexcept

Returns a read-only (constant) iterator that points one past the last element in the unordered_set.

Definition at line 355 of file unordered_set.h.

◆ cend() [2/2]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
const_local_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::cend ( size_type  __n) const
inline

Returns a read-only (constant) iterator pointing to one past the last bucket elements.

Parameters
__nThe bucket index.
Returns
A read-only local iterator.

Definition at line 816 of file unordered_set.h.

◆ clear()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
void std::unordered_set< _Value, _Hash, _Pred, _Alloc >::clear ( )
inlinenoexcept

Erases all elements in an unordered_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 responsibility.

Definition at line 573 of file unordered_set.h.

◆ count()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
size_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::count ( const key_type __x) const
inline

Finds the number of elements.

Parameters
__xElement to located.
Returns
Number of elements with specified key.

This function only makes sense for unordered_multisets; for unordered_set the result will either be 0 (not present) or 1 (present).

Definition at line 685 of file unordered_set.h.

◆ emplace()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
template<typename... _Args>
std::pair<iterator, bool> std::unordered_set< _Value, _Hash, _Pred, _Alloc >::emplace ( _Args &&...  __args)
inline

Attempts to build and insert an element into the unordered_set.

Parameters
__argsArguments used to generate an element.
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 build and insert an element into the unordered_set. An unordered_set relies on unique keys and thus an element is only inserted if it is not already present in the unordered_set.

Insertion requires amortized constant time.

Definition at line 377 of file unordered_set.h.

◆ emplace_hint()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
template<typename... _Args>
iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::emplace_hint ( const_iterator  __pos,
_Args &&...  __args 
)
inline

Attempts to insert an element into the unordered_set.

Parameters
__posAn iterator that serves as a hint as to where the element should be inserted.
__argsArguments used to generate the element to be inserted.
Returns
An iterator that points to the element with key equivalent to the one generated from __args (may or may not be the element itself).

This function is not concerned about whether the insertion took place, and thus does not return a boolean like the single-argument emplace() 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.

For more on hinting, see: https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints

Insertion requires amortized constant time.

Definition at line 403 of file unordered_set.h.

◆ empty()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
bool std::unordered_set< _Value, _Hash, _Pred, _Alloc >::empty ( ) const
inlinenoexcept

Returns true if the unordered_set is empty.

Definition at line 299 of file unordered_set.h.

◆ end() [1/4]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
const_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::end ( ) const
inlinenoexcept

Returns a read-only (constant) iterator that points one past the last element in the unordered_set.

Definition at line 338 of file unordered_set.h.

◆ end() [2/4]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::end ( )
inlinenoexcept

Returns a read-only (constant) iterator that points one past the last element in the unordered_set.

Definition at line 334 of file unordered_set.h.

◆ end() [3/4]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
local_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::end ( size_type  __n)
inline

Returns a read-only (constant) iterator pointing to one past the last bucket elements.

Parameters
__nThe bucket index.
Returns
A read-only local iterator.

Definition at line 808 of file unordered_set.h.

◆ end() [4/4]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
const_local_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::end ( size_type  __n) const
inline

Returns a read-only (constant) iterator pointing to one past the last bucket elements.

Parameters
__nThe bucket index.
Returns
A read-only local iterator.

Definition at line 812 of file unordered_set.h.

◆ equal_range() [1/2]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
std::pair<iterator, iterator> std::unordered_set< _Value, _Hash, _Pred, _Alloc >::equal_range ( const key_type __x)
inline

Finds a subsequence matching given key.

Parameters
__xKey to be located.
Returns
Pair of iterators that possibly points to the subsequence matching given key.

This function probably only makes sense for multisets.

Definition at line 726 of file unordered_set.h.

◆ equal_range() [2/2]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
std::pair<const_iterator, const_iterator> std::unordered_set< _Value, _Hash, _Pred, _Alloc >::equal_range ( const key_type __x) const
inline

Finds a subsequence matching given key.

Parameters
__xKey to be located.
Returns
Pair of iterators that possibly points to the subsequence matching given key.

This function probably only makes sense for multisets.

Definition at line 738 of file unordered_set.h.

◆ erase() [1/4]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
size_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::erase ( const key_type __x)
inline

Erases elements according to the provided key.

Parameters
__xKey of element to be erased.
Returns
The number of elements erased.

This function erases all the elements located by the given key from an unordered_set. For an unordered_set the result of this function can only be 0 (not present) or 1 (present). 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 responsibility.

Definition at line 545 of file unordered_set.h.

◆ erase() [2/4]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::erase ( const_iterator  __first,
const_iterator  __last 
)
inline

Erases a [__first,__last) range of elements from an unordered_set.

Parameters
__firstIterator pointing to the start of the range to be erased.
__lastIterator pointing to the end of the range to be erased.
Returns
The iterator __last.

This function erases a sequence of elements from an unordered_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 responsibility.

Definition at line 563 of file unordered_set.h.

◆ erase() [3/4]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::erase ( const_iterator  __position)
inline

Erases an element from an unordered_set.

Parameters
__positionAn iterator pointing to the element to be erased.
Returns
An iterator pointing to the element immediately following __position prior to the element being erased. If no such element exists, end() is returned.

This function erases an element, pointed to by the given iterator, from an unordered_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 responsibility.

Definition at line 523 of file unordered_set.h.

◆ erase() [4/4]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::erase ( iterator  __position)
inline

Erases an element from an unordered_set.

Parameters
__positionAn iterator pointing to the element to be erased.
Returns
An iterator pointing to the element immediately following __position prior to the element being erased. If no such element exists, end() is returned.

This function erases an element, pointed to by the given iterator, from an unordered_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 responsibility.

Definition at line 528 of file unordered_set.h.

◆ extract() [1/2]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
node_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::extract ( const key_type __key)
inline

Extract a node.

Definition at line 494 of file unordered_set.h.

◆ extract() [2/2]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
node_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::extract ( const_iterator  __pos)
inline

Extract a node.

Definition at line 486 of file unordered_set.h.

◆ find() [1/2]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::find ( const key_type __x)
inline

Tries to locate an element in an unordered_set.

Parameters
__xElement 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.

Definition at line 650 of file unordered_set.h.

◆ find() [2/2]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
const_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::find ( const key_type __x) const
inline

Tries to locate an element in an unordered_set.

Parameters
__xElement 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.

Definition at line 662 of file unordered_set.h.

◆ get_allocator()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
allocator_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::get_allocator ( ) const
inlinenoexcept

Returns the allocator object used by the unordered_set.

Definition at line 292 of file unordered_set.h.

◆ hash_function()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
hasher std::unordered_set< _Value, _Hash, _Pred, _Alloc >::hash_function ( ) const
inline

Returns the hash functor object with which the unordered_set was constructed.

Definition at line 626 of file unordered_set.h.

◆ insert() [1/8]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
template<typename _InputIterator >
void std::unordered_set< _Value, _Hash, _Pred, _Alloc >::insert ( _InputIterator  __first,
_InputIterator  __last 
)
inline

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

Parameters
__firstIterator pointing to the start of the range to be inserted.
__lastIterator pointing to the end of the range.

Complexity similar to that of the range constructor.

Definition at line 469 of file unordered_set.h.

◆ insert() [2/8]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
std::pair<iterator, bool> std::unordered_set< _Value, _Hash, _Pred, _Alloc >::insert ( const value_type __x)
inline

Attempts to insert an element into the unordered_set.

Parameters
__xElement 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 unordered_set. An unordered_set relies on unique keys and thus an element is only inserted if it is not already present in the unordered_set.

Insertion requires amortized constant time.

Definition at line 421 of file unordered_set.h.

◆ insert() [3/8]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::insert ( const_iterator  __hint,
const value_type __x 
)
inline

Attempts to insert an element into the unordered_set.

Parameters
__hintAn iterator that serves as a hint as to where the element should be inserted.
__xElement 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.

For more on hinting, see: https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints

Insertion requires amortized constant.

Definition at line 450 of file unordered_set.h.

◆ insert() [4/8]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::insert ( const_iterator  __hint,
value_type &&  __x 
)
inline

Attempts to insert an element into the unordered_set.

Parameters
__hintAn iterator that serves as a hint as to where the element should be inserted.
__xElement 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.

For more on hinting, see: https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints

Insertion requires amortized constant.

Definition at line 454 of file unordered_set.h.

References std::move().

◆ insert() [5/8]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::insert ( const_iterator  ,
node_type &&  __nh 
)
inline

◆ insert() [6/8]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
void std::unordered_set< _Value, _Hash, _Pred, _Alloc >::insert ( initializer_list< value_type __l)
inline

Attempts to insert a list of elements into the unordered_set.

Parameters
__lA std::initializer_list<value_type> of elements to be inserted.

Complexity similar to that of the range constructor.

Definition at line 480 of file unordered_set.h.

◆ insert() [7/8]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
insert_return_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::insert ( node_type &&  __nh)
inline

◆ insert() [8/8]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
std::pair<iterator, bool> std::unordered_set< _Value, _Hash, _Pred, _Alloc >::insert ( value_type &&  __x)
inline

Attempts to insert an element into the unordered_set.

Parameters
__xElement 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 unordered_set. An unordered_set relies on unique keys and thus an element is only inserted if it is not already present in the unordered_set.

Insertion requires amortized constant time.

Definition at line 425 of file unordered_set.h.

References std::move().

◆ key_eq()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
key_equal std::unordered_set< _Value, _Hash, _Pred, _Alloc >::key_eq ( ) const
inline

Returns the key comparison object with which the unordered_set was constructed.

Definition at line 632 of file unordered_set.h.

◆ load_factor()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
float std::unordered_set< _Value, _Hash, _Pred, _Alloc >::load_factor ( ) const
inlinenoexcept

Returns the average number of elements per bucket.

Definition at line 824 of file unordered_set.h.

◆ max_bucket_count()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
size_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::max_bucket_count ( ) const
inlinenoexcept

Returns the maximum number of buckets of the unordered_set.

Definition at line 759 of file unordered_set.h.

◆ max_load_factor() [1/2]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
float std::unordered_set< _Value, _Hash, _Pred, _Alloc >::max_load_factor ( ) const
inlinenoexcept

Returns a positive number that the unordered_set tries to keep the load factor less than or equal to.

Definition at line 830 of file unordered_set.h.

◆ max_load_factor() [2/2]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
void std::unordered_set< _Value, _Hash, _Pred, _Alloc >::max_load_factor ( float  __z)
inline

Change the unordered_set maximum load factor.

Parameters
__zThe new maximum load factor.

Definition at line 838 of file unordered_set.h.

◆ max_size()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
size_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::max_size ( ) const
inlinenoexcept

Returns the maximum size of the unordered_set.

Definition at line 309 of file unordered_set.h.

◆ operator=() [1/3]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
unordered_set& std::unordered_set< _Value, _Hash, _Pred, _Alloc >::operator= ( const unordered_set< _Value, _Hash, _Pred, _Alloc > &  )
default

Copy assignment operator.

◆ operator=() [2/3]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
unordered_set& std::unordered_set< _Value, _Hash, _Pred, _Alloc >::operator= ( initializer_list< value_type __l)
inline

Unordered_set list assignment operator.

Parameters
__lAn initializer_list.

This function fills an unordered_set with copies of the elements in the initializer list __l.

Note that the assignment completely changes the unordered_set and that the resulting unordered_set's size is the same as the number of elements assigned.

Definition at line 284 of file unordered_set.h.

◆ operator=() [3/3]

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
unordered_set& std::unordered_set< _Value, _Hash, _Pred, _Alloc >::operator= ( unordered_set< _Value, _Hash, _Pred, _Alloc > &&  )
default

Move assignment operator.

◆ rehash()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
void std::unordered_set< _Value, _Hash, _Pred, _Alloc >::rehash ( size_type  __n)
inline

May rehash the unordered_set.

Parameters
__nThe new number of buckets.

Rehash will occur only if the new number of buckets respect the unordered_set maximum load factor.

Definition at line 849 of file unordered_set.h.

◆ reserve()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
void std::unordered_set< _Value, _Hash, _Pred, _Alloc >::reserve ( size_type  __n)
inline

Prepare the unordered_set for a specified number of elements.

Parameters
__nNumber of elements required.

Same as rehash(ceil(n / max_load_factor())).

Definition at line 860 of file unordered_set.h.

◆ size()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
size_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::size ( ) const
inlinenoexcept

Returns the size of the unordered_set.

Definition at line 304 of file unordered_set.h.

◆ swap()

template<typename _Value , typename _Hash = hash<_Value>, typename _Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>>
void std::unordered_set< _Value, _Hash, _Pred, _Alloc >::swap ( unordered_set< _Value, _Hash, _Pred, _Alloc > &  __x)
inlinenoexcept

Swaps data with another unordered_set.

Parameters
__xAn unordered_set of the same element and allocator types.

This exchanges the elements between two sets in constant time. Note that the global std::swap() function is specialized such that std::swap(s1,s2) will feed to this function.

Definition at line 586 of file unordered_set.h.


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