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 Modifiers 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)

 

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 key key. Elements (if any) with keys equivalent to key are always found in this bucket.

2) Returns the index of the bucket for key that compares equivalent to the value x. Elements (if any) with keys that compare equivalent to x are always found in this bucket. This overload participates in overload resolution only if Hash::is_transparent and KeyEqual::is_transparent are valid and each denotes a type. This assumes that such Hash is callable with both K and Key type, and that the KeyEqual is transparent, which, together, allows calling this function without constructing an instance of Key.

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

The behavior is undefined if bucket_count() is zero.

Parameters

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

Return value

Bucket index for the requested key.

Complexity

Constant.

Notes

Feature-test macro	Value	Std	Feature
__cpp_lib_associative_heterogeneous_insertion	202311L	(C++26)	Heterogeneous overloads for the remaining member functions in ordered and unordered associative containers. (2)

See also

bucket_size

returns the number of elements in specific bucket (public member function)