std::unordered_multimap<Key,T,Hash,KeyEqual,Allocator>::bucket

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std::unordered_multimap

Member types

Member functions

unordered_multimap::unordered_multimap
unordered_multimap::~unordered_multimap
unordered_multimap::operator=
unordered_multimap::get_allocator
Iterators
unordered_multimap::beginunordered_multimap::cbegin
unordered_multimap::endunordered_multimap::cend
Capacity
unordered_multimap::size
unordered_multimap::max_size
unordered_multimap::empty
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unordered_multimap::clear
unordered_multimap::insert
unordered_multimap::insert_range (C++23)
unordered_multimap::emplace
unordered_multimap::emplace_hint
unordered_multimap::erase
unordered_multimap::swap
unordered_multimap::extract (C++17)
unordered_multimap::merge (C++17)

Lookup
unordered_multimap::count
unordered_multimap::find
unordered_multimap::contains (C++20)
unordered_multimap::equal_range
Bucket interface
unordered_multimap::begin(size_type)unordered_multimap::cbegin(size_type)
unordered_multimap::end(size_type)unordered_multimap::cend(size_type)
unordered_multimap::bucket_count
unordered_multimap::max_bucket_count
unordered_multimap::bucket_size
unordered_multimap::bucket
Hash policy
unordered_multimap::load_factor
unordered_multimap::max_load_factor
unordered_multimap::rehash
unordered_multimap::reserve
Observers
unordered_multimap::hash_function
unordered_multimap::key_eq

Non-member functions

std::swap(std::unordered_multimap)
erase_if(std::unordered_multimap) (C++20)

operator==operator!=

(until C++20)

Deduction guides(C++17)

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size_type bucket(const Key& key)const;	(1)	(since C++11)
template<typename K> size_type bucket(const K& x)const;	(2)	(since C++26)

1) Returns the index of the bucket for keykey. Elements (if any) with keys equivalent tokey are always found in this bucket.

2) Returns the index of the bucket for key that comparesequivalent to the valuex. Elements (if any) with keys that compare equivalent tox are always found in this bucket. This overload participates in overload resolution only ifHash andKeyEqual are bothtransparent. This assumes that suchHash is callable with bothK andKey type, and that theKeyEqual is transparent, which, together, allows calling this function without constructing an instance ofKey.

The returned value is valid only for instances of the container for whichbucket_count() returns the same value (e.g.,rehash() invalidates previously obtained value).

The behavior is undefined ifbucket_count() is zero.

[edit]Parameters

key	-	the value of the key to examine
x	-	a value of any type that can be transparently compared with a key

[edit]Return value

Bucket index for the requested key.

[edit]Complexity

Constant.

[edit]Notes

Feature-test macro	Value	Std	Feature
`__cpp_lib_associative_heterogeneous_insertion`	`202311L`	(C++26)	Heterogeneous overloads for the remaining member functions inordered andunordered associativecontainers.(2)