libstdc++
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#include <unordered_set.h>
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_set & | operator= (const unordered_set &)=default |
unordered_set & | operator= (initializer_list< value_type > __l) |
unordered_set & | operator= (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) |
template<typename _Kt > | |
auto | find (const _Kt &__k) -> decltype(_M_h._M_find_tr(__k)) |
const_iterator | find (const key_type &__x) const |
template<typename _Kt > | |
auto | find (const _Kt &__k) const -> decltype(_M_h._M_find_tr(__k)) |
size_type | count (const key_type &__x) const |
template<typename _Kt > | |
auto | count (const _Kt &__k) const -> decltype(_M_h._M_count_tr(__k)) |
bool | contains (const key_type &__x) const |
template<typename _Kt > | |
auto | contains (const _Kt &__k) const -> decltype(_M_h._M_find_tr(__k), void(), true) |
std::pair< iterator, iterator > | equal_range (const key_type &__x) |
template<typename _Kt > | |
auto | equal_range (const _Kt &__k) -> decltype(_M_h._M_equal_range_tr(__k)) |
std::pair< const_iterator, const_iterator > | equal_range (const key_type &__x) const |
template<typename _Kt > | |
auto | equal_range (const _Kt &__k) const -> decltype(_M_h._M_equal_range_tr(__k)) |
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 |
A standard container composed of unique keys (containing at most one of each key value) in which the elements' keys are the elements themselves.
_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 102 of file unordered_set.h.
typedef _Hashtable::allocator_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::allocator_type |
Public typedefs.
Definition at line 115 of file unordered_set.h.
typedef _Hashtable::const_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::const_iterator |
Iterator-related typedefs.
Definition at line 125 of file unordered_set.h.
typedef _Hashtable::const_local_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::const_local_iterator |
Iterator-related typedefs.
Definition at line 127 of file unordered_set.h.
typedef _Hashtable::const_pointer std::unordered_set< _Value, _Hash, _Pred, _Alloc >::const_pointer |
Iterator-related typedefs.
Definition at line 121 of file unordered_set.h.
typedef _Hashtable::const_reference std::unordered_set< _Value, _Hash, _Pred, _Alloc >::const_reference |
Iterator-related typedefs.
Definition at line 123 of file unordered_set.h.
typedef _Hashtable::difference_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::difference_type |
Iterator-related typedefs.
Definition at line 129 of file unordered_set.h.
typedef _Hashtable::hasher std::unordered_set< _Value, _Hash, _Pred, _Alloc >::hasher |
Public typedefs.
Definition at line 113 of file unordered_set.h.
using std::unordered_set< _Value, _Hash, _Pred, _Alloc >::insert_return_type = typename _Hashtable::insert_return_type |
Definition at line 134 of file unordered_set.h.
typedef _Hashtable::iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::iterator |
Iterator-related typedefs.
Definition at line 124 of file unordered_set.h.
typedef _Hashtable::key_equal std::unordered_set< _Value, _Hash, _Pred, _Alloc >::key_equal |
Public typedefs.
Definition at line 114 of file unordered_set.h.
typedef _Hashtable::key_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::key_type |
Public typedefs.
Definition at line 111 of file unordered_set.h.
typedef _Hashtable::local_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::local_iterator |
Iterator-related typedefs.
Definition at line 126 of file unordered_set.h.
using std::unordered_set< _Value, _Hash, _Pred, _Alloc >::node_type = typename _Hashtable::node_type |
Definition at line 133 of file unordered_set.h.
typedef _Hashtable::pointer std::unordered_set< _Value, _Hash, _Pred, _Alloc >::pointer |
Iterator-related typedefs.
Definition at line 120 of file unordered_set.h.
typedef _Hashtable::reference std::unordered_set< _Value, _Hash, _Pred, _Alloc >::reference |
Iterator-related typedefs.
Definition at line 122 of file unordered_set.h.
typedef _Hashtable::size_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::size_type |
Iterator-related typedefs.
Definition at line 128 of file unordered_set.h.
typedef _Hashtable::value_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::value_type |
Public typedefs.
Definition at line 112 of file unordered_set.h.
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default |
Default constructor.
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inlineexplicit |
Default constructor creates no elements.
__n | Minimal initial number of buckets. |
__hf | A hash functor. |
__eql | A key equality functor. |
__a | An allocator object. |
Definition at line 150 of file unordered_set.h.
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inline |
Builds an unordered_set from a range.
__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 171 of file unordered_set.h.
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default |
Copy constructor.
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default |
Move constructor.
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inlineexplicit |
Creates an unordered_set with no elements.
__a | An allocator object. |
Definition at line 190 of file unordered_set.h.
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inline |
Definition at line 199 of file unordered_set.h.
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inlinenoexcept |
Definition at line 209 of file unordered_set.h.
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inline |
Builds an unordered_set from an initializer_list.
__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 226 of file unordered_set.h.
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inline |
Definition at line 234 of file unordered_set.h.
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inline |
Definition at line 238 of file unordered_set.h.
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inline |
Definition at line 244 of file unordered_set.h.
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inline |
Definition at line 251 of file unordered_set.h.
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inline |
Definition at line 257 of file unordered_set.h.
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inline |
Definition at line 263 of file unordered_set.h.
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inlinenoexcept |
Returns a read-only (constant) iterator that points to the first element in the unordered_set.
Definition at line 329 of file unordered_set.h.
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inlinenoexcept |
Returns a read-only (constant) iterator that points to the first element in the unordered_set.
Definition at line 325 of file unordered_set.h.
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inline |
Returns a read-only (constant) iterator pointing to the first bucket element.
__n | The bucket index. |
Definition at line 793 of file unordered_set.h.
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inline |
Returns a read-only (constant) iterator pointing to the first bucket element.
__n | The bucket index. |
Definition at line 797 of file unordered_set.h.
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inline |
Definition at line 782 of file unordered_set.h.
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inlinenoexcept |
Returns the number of buckets of the unordered_set.
Definition at line 759 of file unordered_set.h.
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inline |
Definition at line 773 of file unordered_set.h.
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inlinenoexcept |
Returns a read-only (constant) iterator that points to the first element in the unordered_set.
Definition at line 352 of file unordered_set.h.
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inline |
Returns a read-only (constant) iterator pointing to the first bucket element.
__n | The bucket index. |
Definition at line 801 of file unordered_set.h.
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inlinenoexcept |
Returns a read-only (constant) iterator that points one past the last element in the unordered_set.
Definition at line 360 of file unordered_set.h.
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inline |
Returns a read-only (constant) iterator pointing to one past the last bucket elements.
__n | The bucket index. |
Definition at line 821 of file unordered_set.h.
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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 578 of file unordered_set.h.
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inline |
Finds whether an element with the given key exists.
__x | Key of elements to be located. |
Definition at line 715 of file unordered_set.h.
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inline |
Finds whether an element with the given key exists.
__x | Key of elements to be located. |
Definition at line 710 of file unordered_set.h.
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inline |
Finds the number of elements.
__x | Element to located. |
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 696 of file unordered_set.h.
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inline |
Finds the number of elements.
__x | Element to located. |
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 690 of file unordered_set.h.
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inline |
Attempts to build and insert an element into the unordered_set.
__args | Arguments used to generate an element. |
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 382 of file unordered_set.h.
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inline |
Attempts to insert an element into the unordered_set.
__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. |
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 408 of file unordered_set.h.
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inlinenoexcept |
Returns true if the unordered_set is empty.
Definition at line 304 of file unordered_set.h.
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inlinenoexcept |
Returns a read-only (constant) iterator that points one past the last element in the unordered_set.
Definition at line 343 of file unordered_set.h.
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inlinenoexcept |
Returns a read-only (constant) iterator that points one past the last element in the unordered_set.
Definition at line 339 of file unordered_set.h.
Referenced by std::unordered_set< _Value, _Hash, _Pred, _Alloc >::extract().
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inline |
Returns a read-only (constant) iterator pointing to one past the last bucket elements.
__n | The bucket index. |
Definition at line 813 of file unordered_set.h.
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inline |
Returns a read-only (constant) iterator pointing to one past the last bucket elements.
__n | The bucket index. |
Definition at line 817 of file unordered_set.h.
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inline |
Finds a subsequence matching given key.
__x | Key to be located. |
This function probably only makes sense for multisets.
Definition at line 737 of file unordered_set.h.
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inline |
Finds a subsequence matching given key.
__x | Key to be located. |
This function probably only makes sense for multisets.
Definition at line 749 of file unordered_set.h.
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inline |
Finds a subsequence matching given key.
__x | Key to be located. |
This function probably only makes sense for multisets.
Definition at line 731 of file unordered_set.h.
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inline |
Finds a subsequence matching given key.
__x | Key to be located. |
This function probably only makes sense for multisets.
Definition at line 743 of file unordered_set.h.
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inline |
Erases elements according to the provided key.
__x | Key of element to be 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 550 of file unordered_set.h.
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inline |
Erases a [__first,__last) range of elements from an unordered_set.
__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 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 568 of file unordered_set.h.
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inline |
Erases an element from an unordered_set.
__position | An iterator pointing to the element to be erased. |
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.
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inline |
Erases an element from an unordered_set.
__position | An iterator pointing to the element to be erased. |
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 533 of file unordered_set.h.
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inline |
Extract a node.
Definition at line 499 of file unordered_set.h.
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inline |
Extract a node.
Definition at line 491 of file unordered_set.h.
References std::unordered_set< _Value, _Hash, _Pred, _Alloc >::end().
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inline |
Tries to locate an element in an unordered_set.
__x | Element to be located. |
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 661 of file unordered_set.h.
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inline |
Tries to locate an element in an unordered_set.
__x | Element to be located. |
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 673 of file unordered_set.h.
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inline |
Tries to locate an element in an unordered_set.
__x | Element to be located. |
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 655 of file unordered_set.h.
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inline |
Tries to locate an element in an unordered_set.
__x | Element to be located. |
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 667 of file unordered_set.h.
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inlinenoexcept |
Returns the allocator object used by the unordered_set.
Definition at line 297 of file unordered_set.h.
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inline |
Returns the hash functor object with which the unordered_set was constructed.
Definition at line 631 of file unordered_set.h.
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inline |
A template function that attempts to insert a range of elements.
__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 474 of file unordered_set.h.
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inline |
Attempts to insert an element into the unordered_set.
__x | Element to be 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 426 of file unordered_set.h.
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inline |
Attempts to insert an element into the unordered_set.
__hint | An iterator that serves as a hint as to where the element should be inserted. |
__x | Element to be inserted. |
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 455 of file unordered_set.h.
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inline |
Attempts to insert an element into the unordered_set.
__hint | An iterator that serves as a hint as to where the element should be inserted. |
__x | Element to be inserted. |
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 459 of file unordered_set.h.
References std::move().
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inline |
Re-insert an extracted node.
Definition at line 509 of file unordered_set.h.
References std::move().
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inline |
Attempts to insert a list of elements into the unordered_set.
__l | A std::initializer_list<value_type> of elements to be inserted. |
Complexity similar to that of the range constructor.
Definition at line 485 of file unordered_set.h.
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inline |
Re-insert an extracted node.
Definition at line 504 of file unordered_set.h.
References std::move().
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inline |
Attempts to insert an element into the unordered_set.
__x | Element to be 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 430 of file unordered_set.h.
References std::move().
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inline |
Returns the key comparison object with which the unordered_set was constructed.
Definition at line 637 of file unordered_set.h.
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inlinenoexcept |
Returns the average number of elements per bucket.
Definition at line 829 of file unordered_set.h.
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inlinenoexcept |
Returns the maximum number of buckets of the unordered_set.
Definition at line 764 of file unordered_set.h.
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inlinenoexcept |
Returns a positive number that the unordered_set tries to keep the load factor less than or equal to.
Definition at line 835 of file unordered_set.h.
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inline |
Change the unordered_set maximum load factor.
__z | The new maximum load factor. |
Definition at line 843 of file unordered_set.h.
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inlinenoexcept |
Returns the maximum size of the unordered_set.
Definition at line 314 of file unordered_set.h.
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inline |
Definition at line 622 of file unordered_set.h.
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inline |
Definition at line 614 of file unordered_set.h.
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inline |
Definition at line 609 of file unordered_set.h.
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inline |
Definition at line 601 of file unordered_set.h.
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default |
Copy assignment operator.
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inline |
Unordered_set list assignment operator.
__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 289 of file unordered_set.h.
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default |
Move assignment operator.
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inline |
May rehash the unordered_set.
__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 854 of file unordered_set.h.
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inline |
Prepare the unordered_set for a specified number of elements.
__n | Number of elements required. |
Same as rehash(ceil(n / max_load_factor())).
Definition at line 865 of file unordered_set.h.
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inlinenoexcept |
Returns the size of the unordered_set.
Definition at line 309 of file unordered_set.h.
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inlinenoexcept |
Swaps data with another unordered_set.
__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 591 of file unordered_set.h.
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friend |
Definition at line 597 of file unordered_set.h.