libstdc++
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#include <unordered_set>
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 107 of file unordered_set.h.
typedef _Hashtable::allocator_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::allocator_type |
Public typedefs.
Definition at line 120 of file unordered_set.h.
typedef _Hashtable::const_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::const_iterator |
Iterator-related typedefs.
Definition at line 130 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 132 of file unordered_set.h.
typedef _Hashtable::const_pointer std::unordered_set< _Value, _Hash, _Pred, _Alloc >::const_pointer |
Iterator-related typedefs.
Definition at line 126 of file unordered_set.h.
typedef _Hashtable::const_reference std::unordered_set< _Value, _Hash, _Pred, _Alloc >::const_reference |
Iterator-related typedefs.
Definition at line 128 of file unordered_set.h.
typedef _Hashtable::difference_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::difference_type |
Iterator-related typedefs.
Definition at line 134 of file unordered_set.h.
typedef _Hashtable::hasher std::unordered_set< _Value, _Hash, _Pred, _Alloc >::hasher |
Public typedefs.
Definition at line 118 of file unordered_set.h.
using std::unordered_set< _Value, _Hash, _Pred, _Alloc >::insert_return_type = typename _Hashtable::insert_return_type |
Definition at line 139 of file unordered_set.h.
typedef _Hashtable::iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::iterator |
Iterator-related typedefs.
Definition at line 129 of file unordered_set.h.
typedef _Hashtable::key_equal std::unordered_set< _Value, _Hash, _Pred, _Alloc >::key_equal |
Public typedefs.
Definition at line 119 of file unordered_set.h.
typedef _Hashtable::key_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::key_type |
Public typedefs.
Definition at line 116 of file unordered_set.h.
typedef _Hashtable::local_iterator std::unordered_set< _Value, _Hash, _Pred, _Alloc >::local_iterator |
Iterator-related typedefs.
Definition at line 131 of file unordered_set.h.
using std::unordered_set< _Value, _Hash, _Pred, _Alloc >::node_type = typename _Hashtable::node_type |
Definition at line 138 of file unordered_set.h.
typedef _Hashtable::pointer std::unordered_set< _Value, _Hash, _Pred, _Alloc >::pointer |
Iterator-related typedefs.
Definition at line 125 of file unordered_set.h.
typedef _Hashtable::reference std::unordered_set< _Value, _Hash, _Pred, _Alloc >::reference |
Iterator-related typedefs.
Definition at line 127 of file unordered_set.h.
typedef _Hashtable::size_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::size_type |
Iterator-related typedefs.
Definition at line 133 of file unordered_set.h.
typedef _Hashtable::value_type std::unordered_set< _Value, _Hash, _Pred, _Alloc >::value_type |
Public typedefs.
Definition at line 117 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 155 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 176 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 195 of file unordered_set.h.
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inline |
Definition at line 204 of file unordered_set.h.
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inlinenoexcept |
Definition at line 214 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 231 of file unordered_set.h.
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inline |
Definition at line 239 of file unordered_set.h.
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inline |
Definition at line 243 of file unordered_set.h.
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inline |
Definition at line 249 of file unordered_set.h.
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inline |
Definition at line 256 of file unordered_set.h.
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inline |
Definition at line 262 of file unordered_set.h.
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inline |
Definition at line 268 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 370 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 366 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 859 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 863 of file unordered_set.h.
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inline |
Definition at line 848 of file unordered_set.h.
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inlinenoexcept |
Returns the number of buckets of the unordered_set.
Definition at line 825 of file unordered_set.h.
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inline |
Definition at line 839 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 393 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 867 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 401 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 887 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 637 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 781 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 776 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 762 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 756 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 423 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 449 of file unordered_set.h.
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inlinenoexcept |
Returns true if the unordered_set is empty.
Definition at line 345 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 384 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 380 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 879 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 883 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 803 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 815 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 797 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 809 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 609 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 627 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 587 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 592 of file unordered_set.h.
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inline |
Extract a node.
Definition at line 558 of file unordered_set.h.
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inline |
Extract a node.
Definition at line 550 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 727 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 739 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 721 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 733 of file unordered_set.h.
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inlinenoexcept |
Returns the allocator object used by the unordered_set.
Definition at line 338 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 697 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 515 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 467 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 496 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 500 of file unordered_set.h.
References std::move().
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inline |
Re-insert an extracted node.
Definition at line 568 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 526 of file unordered_set.h.
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inline |
Re-insert an extracted node.
Definition at line 563 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 471 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 703 of file unordered_set.h.
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inlinenoexcept |
Returns the average number of elements per bucket.
Definition at line 895 of file unordered_set.h.
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inlinenoexcept |
Returns the maximum number of buckets of the unordered_set.
Definition at line 830 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 901 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 909 of file unordered_set.h.
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inlinenoexcept |
Returns the maximum size of the unordered_set.
Definition at line 355 of file unordered_set.h.
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inline |
Definition at line 688 of file unordered_set.h.
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inline |
Definition at line 680 of file unordered_set.h.
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inline |
Definition at line 672 of file unordered_set.h.
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inline |
Definition at line 660 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 330 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 920 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 931 of file unordered_set.h.
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inlinenoexcept |
Returns the size of the unordered_set.
Definition at line 350 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 650 of file unordered_set.h.
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friend |
Definition at line 656 of file unordered_set.h.