std::unordered_multiset::reserve

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C++ Standard Library
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Containers library
array (C++11) vector deque forward_list (C++11) list set multiset map multimap unordered_set (C++11) unordered_multiset (C++11) unordered_map (C++11) unordered_multimap (C++11) stack queue priority_queue
std::unordered_multiset
Member functions unordered_multiset::unordered_multiset unordered_multiset::~unordered_multiset unordered_multiset::operator= unordered_multiset::get_allocator Iterators unordered_multiset::begin unordered_multiset::cbegin unordered_multiset::end unordered_multiset::cend Capacity unordered_multiset::erase unordered_multiset::size unordered_multiset::max_size Modifiers unordered_multiset::clear unordered_multiset::insert unordered_multiset::emplace unordered_multiset::emplace_hint unordered_multiset::erase unordered_multiset::swap Lookup unordered_multiset::count unordered_multiset::find unordered_multiset::equal_range Bucket interface unordered_multiset::begin(int) unordered_multiset::end(int) 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

void reserve( size_type count );		(C++11 feature)

Sets the number of buckets to the number needed to accomodate at least count elements without exceeding maximum load factor and rehashes the container, i.e. puts the elements into appropriate buckets considering that total number of buckets has changed. Effectively calls {{cpp|rehash(std::ceil(count / max_load_factor())).

Contents 1 Parameters 2 Return value 3 Complexity 4 See also

[edit] Parameters

count

-

new capacity of the container

[edit] Return value

(none)

[edit] Complexity

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

[edit] See also

rehash	reserves at least the specified number of buckets. This regenerates the hash table. (public member function)