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

 

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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)

 

iterator insert( const value_type& value );	(1)	(since C++11)
iterator insert( value_type&& value );	(2)	(since C++11)
iterator insert( const_iterator hint, const value_type& value );	(3)	(since C++11)
iterator insert( const_iterator hint, value_type&& value );	(4)	(since C++11)
template< class InputIt > void insert( InputIt first, InputIt last );	(5)	(since C++11)
void insert( std::initializer_list<value_type> ilist );	(6)	(since C++11)
iterator insert( node_type&& nh );	(7)	(since C++17)
iterator insert( const_iterator hint, node_type&& nh );	(8)	(since C++17)

Inserts element(s) into the container.

1,2) Inserts value.

3,4) Inserts value, using hint as a non-binding suggestion to where the search should start.

5) Inserts elements from range [first, last).

6) Inserts elements from initializer list ilist.

7) If nh is an empty node handle, does nothing. Otherwise, inserts the element owned by nh into the container and returns an iterator pointing at the inserted element. The behavior is undefined if nh is not empty and get_allocator() != nh.get_allocator().

8) If nh is an empty node handle, does nothing and returns the end iterator. Otherwise, inserts the element owned by nh into the container, and returns the iterator pointing to the element with key equivalent to nh.key(). hint is used as a non-binding suggestion to where the search should start. The behavior is undefined if nh is not empty and get_allocator() != nh.get_allocator().

If after the operation the new number of elements is greater than old max_load_factor() * bucket_count() a rehashing takes place.
If rehashing occurs (due to the insertion), all iterators are invalidated. Otherwise (no rehashing), iterators are not invalidated. If the insertion is successful, pointers and references to the element obtained while it is held in the node handle are invalidated, and pointers and references obtained to that element before it was extracted become valid.(since C++17)

Parameters

hint	-	iterator, used as a suggestion as to where to insert the content
value	-	element value to insert
first, last	-	range of elements to insert
ilist	-	initializer list to insert the values from
nh	-	a compatible node handle
Type requirements
- InputIt must meet the requirements of LegacyInputIterator.

Return value

1-4) An iterator to the inserted element.

5,6) (none)

7,8) End iterator if nh was empty, iterator pointing to the inserted element otherwise.

Exceptions

1-4) If an exception is thrown by any operation, the insertion has no effect.

Complexity

1-4) Average case: O(1), worst case O(size()).

5,6) Average case: O(N), where N is the number of elements to insert. Worst case: O(N * size() + N).

7,8) Average case: O(1), worst case O(size()).

See also

emplace	constructs element in-place (public member function)
emplace_hint	constructs elements in-place using a hint (public member function)
inserter	creates a std::insert_iterator of type inferred from the argument (function template)