std::unordered_set<Key,Hash,KeyEqual,Allocator>::bucket

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std::unordered_set

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unordered_set::unordered_set
unordered_set::~unordered_set
unordered_set::operator=
unordered_set::get_allocator
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unordered_set::beginunordered_set::cbegin
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unordered_set::count
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unordered_set::equal_range
Bucket interface
unordered_set::begin(size_type)unordered_set::cbegin(size_type)
unordered_set::end(size_type)unordered_set::cend(size_type)
unordered_set::bucket_count
unordered_set::max_bucket_count
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unordered_set::bucket
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unordered_set::hash_function
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operator==operator!=

(until C++20)

std::swap(std::unordered_set)
erase_if(std::unordered_set) (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)