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

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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::size unordered_multiset::max_size unordered_multiset::empty 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(std::unordered_multiset) erase_if(std::unordered_multiset) (C++20)
Deduction guides (C++17)

 

size_type size() const noexcept;		(since C++11)

Returns the number of elements in the container, i.e. std::distance(begin(), end()).

Return value

The number of elements in the container.

Complexity

Constant.

Example

Run this code

#include <cassert>
#include <unordered_set>
 
int main()
{
    std::unordered_multiset<int> nums{4, 2, 4, 2};
    assert(nums.size() == 4);
}

See also

empty	checks whether the container is empty (public member function)
max_size	returns the maximum possible number of elements (public member function)
sizessize (C++17)(C++20)	returns the size of a container or array (function template)