std::unordered_multiset<Key,Hash,KeyEqual,Allocator>::rehash

 

C++

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Feature test macros (C++20)

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External libraries

 

Containers library

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array (C++11)

vector

vector<bool>

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forward_list (C++11)

list

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multiset

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unordered_set (C++11)

unordered_multiset (C++11)

unordered_map (C++11)

unordered_multimap (C++11)

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stack

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std::unordered_multiset

Member types

Member functions

unordered_multiset::unordered_multiset

unordered_multiset::~unordered_multiset

unordered_multiset::operator=

unordered_multiset::get_allocator

Iterators

unordered_multiset::beginunordered_multiset::cbegin

unordered_multiset::endunordered_multiset::cend

Capacity

unordered_multiset::empty

unordered_multiset::size

unordered_multiset::max_size

Modifiers

unordered_multiset::clear

unordered_multiset::insert

unordered_multiset::insert_range (C++23)

unordered_multiset::emplace

unordered_multiset::emplace_hint

unordered_multiset::erase

unordered_multiset::swap

unordered_multiset::extract (C++17)

unordered_multiset::merge (C++17)

Lookup

unordered_multiset::count

unordered_multiset::find

unordered_multiset::contains (C++20)

unordered_multiset::equal_range

Bucket interface

unordered_multiset::begin(size_type)unordered_multiset::cbegin(size_type)

unordered_multiset::end(size_type)unordered_multiset::cend(size_type)

unordered_multiset::bucket_count

unordered_multiset::max_bucket_count

unordered_multiset::bucket_size

unordered_multiset::bucket

Hash policy

unordered_multiset::load_factor

unordered_multiset::max_load_factor

unordered_multiset::rehash

unordered_multiset::reserve

Observers

unordered_multiset::hash_function

unordered_multiset::key_eq

Non-member functions

operator==operator!= (until C++20)

std::swap

erase_if (C++20)

Deduction guides(C++17)

 

void rehash( size_type count );		(since C++11)

Changes the number of buckets to a value n that is not less than count and satisfies n >= size() / max_load_factor(), then rehashes the container, i.e. puts the elements into appropriate buckets considering that total number of buckets has changed.

Parameters

count

-

lower bound for the new number of buckets

Return value

(none)

Complexity

Average case linear in the size of the container, worst case quadratic.

Notes

rehash(0) may be used to force an unconditional rehash, such as after suspension of automatic rehashing by temporarily increasing max_load_factor().

See also

reserve (C++11)

reserves space for at least the specified number of elements and regenerates the hash table (public member function)