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

 

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std::unordered_set

Member types
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unordered_set::unordered_set unordered_set::~unordered_set unordered_set::operator= unordered_set::get_allocator Iterators unordered_set::beginunordered_set::cbegin unordered_set::endunordered_set::cend Capacity unordered_set::size unordered_set::max_size unordered_set::empty Modifiers unordered_set::clear unordered_set::erase unordered_set::swap unordered_set::extract (C++17) unordered_set::merge (C++17) unordered_set::insert unordered_set::insert_range (C++23)   unordered_set::emplace unordered_set::emplace_hint	Lookup unordered_set::count unordered_set::find unordered_set::contains (C++20) 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 unordered_set::bucket_size unordered_set::bucket Hash policy unordered_set::load_factor unordered_set::max_load_factor unordered_set::rehash unordered_set::reserve Observers unordered_set::hash_function unordered_set::key_eq
Non-member functions
operator==operator!= (until C++20)	std::swap(std::unordered_set) erase_if(std::unordered_set) (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

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

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