Manpages - std_unordered_set.3

using insert_return_type = typename _Hashtable::insert_return_type

using node_type = typename _Hashtable::node_type

typedef _Hashtable::key_type key_type
Public typedefs.

typedef _Hashtable::value_type value_type
Public typedefs.

typedef _Hashtable::hasher hasher
Public typedefs.

typedef _Hashtable::key_equal key_equal
Public typedefs.

typedef _Hashtable::allocator_type allocator_type
Public typedefs.

typedef _Hashtable::pointer pointer
Iterator-related typedefs.

typedef _Hashtable::const_pointer const_pointer
Iterator-related typedefs.

typedef _Hashtable::reference reference
Iterator-related typedefs.

typedef _Hashtable::const_reference const_reference
Iterator-related typedefs.

typedef _Hashtable::iterator iterator
Iterator-related typedefs.

typedef _Hashtable::const_iterator const_iterator
Iterator-related typedefs.

typedef _Hashtable::local_iterator local_iterator
Iterator-related typedefs.

typedef _Hashtable::const_local_iterator const_local_iterator
Iterator-related typedefs.

typedef _Hashtable::size_type size_type
Iterator-related typedefs.

typedef _Hashtable::difference_type difference_type
Iterator-related typedefs.

unordered_set ()=default
Default constructor.

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*())
Builds an unordered_set from a range.

unordered_set (const allocator_type &__a)
Creates an unordered_set with no elements.

unordered_set (const unordered_set &)=default
Copy constructor.

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*())
Builds an unordered_set from an initializer_list.

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*())
Default constructor creates no elements.

unordered_set (unordered_set &&)=default
Move constructor.

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
Returns the number of buckets of the unordered_set.

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)
Attempts to build and insert an element into the unordered_set.

template<typename… _Args> iterator emplace_hint (const_iterator __pos, _Args &&… __args)
Attempts to insert an element into the unordered_set.

bool empty () const noexcept
Returns true if the unordered_set is empty.

size_type erase (const key_type &__x)
Erases elements according to the provided key.

iterator erase (const_iterator __first, const_iterator __last)
Erases a [__first,__last) range of elements from an unordered_set.

node_type extract (const key_type &__key)
Extract a node.

node_type extract (const_iterator __pos)
Extract a node.

allocator_type get_allocator () const noexcept
Returns the allocator object used by the unordered_set.

hasher hash_function () const
Returns the hash functor object with which the unordered_set was constructed.

template<typename _InputIterator > void insert (_InputIterator __first, _InputIterator __last)
A template function that attempts to insert a range of elements.

iterator insert (const_iterator, node_type &&__nh)
Re-insert an extracted node.

void insert (initializer_list*< *value_type > __l)
Attempts to insert a list of elements into the unordered_set.

insert_return_type insert (node_type &&__nh)
Re-insert an extracted node.

key_equal key_eq () const
Returns the key comparison object with which the unordered_set was constructed.

float load_factor () const noexcept
Returns the average number of elements per bucket.

size_type max_bucket_count () const noexcept
Returns the maximum number of buckets of the unordered_set.

float max_load_factor () const noexcept
Returns a positive number that the unordered_set tries to keep the load factor less than or equal to.

void max_load_factor (float __z)
Change the unordered_set maximum load factor.

size_type max_size () const noexcept
Returns the maximum size of the unordered_set.

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_set & operator= (const unordered_set &)=default
Copy assignment operator.

unordered_set & operator= (initializer_list*< *value_type > __l)
Unordered_set list assignment operator.

unordered_set & operator= (unordered_set &&)=default
Move assignment operator.

void rehash (size_type __n)
May rehash the unordered_set.

void reserve (size_type __n)
Prepare the unordered_set for a specified number of elements.

size_type size () const noexcept
Returns the size of the unordered_set.

void swap (unordered_set &__x) noexcept(noexcept(_M_h.swap(__x._M_h)))
Swaps data with another unordered_set.

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)
Attempts to insert an element into the unordered_set.

std::pair*< *iterator, bool > insert (value_type &&__x)
Attempts to insert an element into the unordered_set.

iterator insert (const_iterator __hint, const value_type &__x)
Attempts to insert an element into the unordered_set.

iterator insert (const_iterator __hint, value_type &&__x)
Attempts to insert an element into the unordered_set.

iterator erase (const_iterator __position)
Erases an element from an unordered_set.

iterator erase (iterator __position)
Erases an element from an unordered_set.

iterator find (const key_type &__x)
Tries to locate an element in an unordered_set.

const_iterator find (const key_type &__x) const
Tries to locate an element in an unordered_set.

size_type count (const key_type &__x) const
Finds the number of elements.

std::pair*< *iterator, iterator > equal_range (const key_type &__x)
Finds a subsequence matching given key.

std::pair*< *const_iterator, const_iterator > equal_range (const key_type &__x) const
Finds a subsequence matching given key.

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

const_local_iterator begin (size_type __n) const
Returns a read-only (constant) iterator pointing to the first bucket element.

const_local_iterator cbegin (size_type __n) const
Returns a read-only (constant) iterator pointing to the first bucket element.

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

const_local_iterator end (size_type __n) const
Returns a read-only (constant) iterator pointing to one past the last bucket elements.

const_local_iterator cend (size_type __n) const
Returns a read-only (constant) iterator pointing to one past the last bucket elements.

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

_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

_Value Type of key objects.
_Hash Hashing function object type, defaults to hash<_Value>.
_Pred Predicate function object type, defaults to equal_to<_Value>.
_Alloc Allocator 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.

_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.

_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.

_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.

_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.

_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.

_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.

_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.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> using std::unordered_set*< _Value, _Hash, _Pred, _Alloc >::insert_return_type = typename *_Hashtable::insert_return_type Definition at line 129 of file unordered_set.h.

_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.

_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.

_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.

_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.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> using std::unordered_set*< _Value, _Hash, _Pred, _Alloc >::node_type = typename *_Hashtable::node_type Definition at line 128 of file unordered_set.h.

_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.

_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.

_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.

_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.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> std::unordered_set*< _Value, _Hash, _Pred, _Alloc >::*unordered_set ()= [default]= Default constructor.

_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*=()=*)*= [inline]=*, *= [explicit]= Default constructor creates no elements.

Parameters

/__n/* Minimal initial number of buckets.
__hf A hash functor.
__eql A key equality functor.
__a An allocator object. *

Definition at line 145 of file unordered_set.h.

_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

/__first/* An input iterator.
__last An input iterator.
__n Minimal initial number of buckets.
__hf A hash functor.
__eql A key equality functor.
__a An 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.

_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.

_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.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> std::unordered_set< _Value, _Hash, _Pred, _Alloc >::unordered_set (const allocator_type & __a)*= [inline]=, *= [explicit]= Creates an unordered_set with no elements.

Parameters

/__a/* An allocator object. *

Definition at line 185 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> std::unordered_set< _Value, _Hash, _Pred, _Alloc >::unordered_set (const unordered_set< _Value, _Hash, _Pred, _Alloc > & __uset, const allocator_type & __a)*= [inline]= Definition at line *194 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> std::unordered_set< _Value, _Hash, _Pred, _Alloc >::unordered_set (unordered_set< _Value, _Hash, _Pred, _Alloc > && __uset, const allocator_type & __a)*= [inline]=, = [noexcept]= Definition at line *204 of file unordered_set.h.

_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

/__l/* An initializer_list.
__n Minimal initial number of buckets.
__hf A hash functor.
__eql A key equality functor.
__a An 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.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> std::unordered_set< _Value, _Hash, _Pred, _Alloc >::unordered_set (size_type __n, const allocator_type & __a)*= [inline]= Definition at line *229 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> std::unordered_set< _Value, _Hash, _Pred, _Alloc >::unordered_set (size_type __n, const hasher & __hf, const allocator_type & __a)*= [inline]= Definition at line *233 of file unordered_set.h.

_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, const allocator_type & __a)*= [inline]= Definition at line *239 of file unordered_set.h.

_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, const hasher & __hf, const allocator_type & __a)*= [inline]= Definition at line *246 of file unordered_set.h.

_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, const allocator_type & __a)*= [inline]= Definition at line *252 of file unordered_set.h.

_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, const hasher & __hf, const allocator_type & __a)*= [inline]= Definition at line *258 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> const_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::begin () const*= [inline]=, *= [noexcept]= 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.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::begin ()*= [inline]=, *= [noexcept]= 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.

_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

/__n/* The bucket index. *

Returns

A read-only local iterator.

Definition at line 788 of file unordered_set.h.

_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

/__n/* The bucket index. *

Returns

A read-only local iterator.

Definition at line 792 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> size_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::bucket (const key_type & __key) const*= [inline]= Definition at line *777 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> size_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::bucket_count () const*= [inline]=, *= [noexcept]= Returns the number of buckets of the unordered_set.

Definition at line 754 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> size_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::bucket_size (size_type __n) const*= [inline]= Definition at line *768 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> const_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::cbegin () const*= [inline]=, *= [noexcept]= 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.

_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

/__n/* The bucket index. *

Returns

A read-only local iterator.

Definition at line 796 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> const_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::cend () const*= [inline]=, *= [noexcept]= 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.

_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

/__n/* The bucket index. *

Returns

A read-only local iterator.

Definition at line 816 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> void std::unordered_set< _Value, _Hash, _Pred, _Alloc >::clear ()*= [inline]=, *= [noexcept]= 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.

_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

/__x/* Element 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.

_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

/__args/* Arguments 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.

_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

/__pos/* An iterator that serves as a hint as to where the element should be inserted.
__args Arguments 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.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> bool std::unordered_set< _Value, _Hash, _Pred, _Alloc >::empty () const*= [inline]=, *= [noexcept]= Returns true if the unordered_set is empty.

Definition at line 299 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> const_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::end () const*= [inline]=, *= [noexcept]= 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.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::end ()*= [inline]=, *= [noexcept]= 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.

_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

/__n/* The bucket index. *

Returns

A read-only local iterator.

Definition at line 808 of file unordered_set.h.

_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

/__n/* The bucket index. *

Returns

A read-only local iterator.

Definition at line 812 of file unordered_set.h.

_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

/__x/* Key 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.

_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

/__x/* Key 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.

_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

/__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 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.

_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

/__first/* Iterator pointing to the start of the range to be erased.
__last Iterator 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.

_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

/__position/* An 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.

_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

/__position/* An 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.

_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.

_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.

_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

/__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. *

Definition at line 650 of file unordered_set.h.

_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

/__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. *

Definition at line 662 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> allocator_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::get_allocator () const*= [inline]=, *= [noexcept]= Returns the allocator object used by the unordered_set.

Definition at line 292 of file unordered_set.h.

_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.

_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

/__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.

Definition at line 469 of file unordered_set.h.

_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

/__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 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.

_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

/__hint/* 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.

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.

_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

/__hint/* 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.

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().

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> *iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::insert (const_iterator, node_type && __nh)*= [inline]= Re-insert an extracted node.

Definition at line 504 of file unordered_set.h.

References std::_Hashtable< _Key, _Value, _Alloc, _ExtractKey, _Equal, _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits >::_M_reinsert_node(), and std::move().

_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

/__l/* A 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.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> insert_return_type *std::unordered_set< _Value, _Hash, _Pred, _Alloc >::insert (node_type && __nh)*= [inline]= Re-insert an extracted node.

Definition at line 499 of file unordered_set.h.

References std::_Hashtable< _Key, _Value, _Alloc, _ExtractKey, _Equal, _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits >::_M_reinsert_node(), and std::move().

_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

/__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 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().

_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.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> float std::unordered_set< _Value, _Hash, _Pred, _Alloc >::load_factor () const*= [inline]=, *= [noexcept]= Returns the average number of elements per bucket.

Definition at line 824 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> size_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::max_bucket_count () const*= [inline]=, *= [noexcept]= Returns the maximum number of buckets of the unordered_set.

Definition at line 759 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> float std::unordered_set< _Value, _Hash, _Pred, _Alloc >::max_load_factor () const*= [inline]=, *= [noexcept]= 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.

_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

/__z/* The new maximum load factor. *

Definition at line 838 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> size_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::max_size () const*= [inline]=, *= [noexcept]= Returns the maximum size of the unordered_set.

Definition at line 309 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> template<typename _H2 , typename _P2 > void std::unordered_set< _Value, _Hash, _Pred, _Alloc >::merge (unordered_multiset< _Value, _H2, _P2, _Alloc > && __source)*= [inline]= Definition at line *617 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> template<typename _H2 , typename _P2 > void std::unordered_set< _Value, _Hash, _Pred, _Alloc >::merge (unordered_multiset< _Value, _H2, _P2, _Alloc > & __source)*= [inline]= Definition at line *609 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> template<typename _H2 , typename _P2 > void std::unordered_set< _Value, _Hash, _Pred, _Alloc >::merge (unordered_set< _Value, _H2, _P2, _Alloc > && __source)*= [inline]= Definition at line *604 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> template<typename _H2 , typename _P2 > void std::unordered_set< _Value, _Hash, _Pred, _Alloc >::merge (unordered_set< _Value, _H2, _P2, _Alloc > & __source)*= [inline]= Definition at line *596 of file unordered_set.h.

_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.

_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

/__l/* An 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.

_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.

_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

/__n/* The 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.

_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

/__n/* Number of elements required.*

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

Definition at line 860 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> size_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::size () const*= [inline]=, *= [noexcept]= Returns the size of the unordered_set.

Definition at line 304 of file unordered_set.h.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> void std::unordered_set< _Value, _Hash, _Pred, _Alloc >::swap (unordered_set< _Value, _Hash, _Pred, _Alloc > & __x)*= [inline]=, *= [noexcept]= Swaps data with another unordered_set.

Parameters

/__x/* An 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.

_Pred = equal_to<_Value>, typename _Alloc = allocator<_Value>> template<typename , typename , typename > friend class std::_Hash_merge_helper= [friend]= Definition at line 592 of file unordered_set.h.