std::unordered_set::emplace_hint

 

C++

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Technical Specifications

 

Containers library

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unordered_multiset (C++11)

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std::unordered_set

Member functions

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::erase

unordered_set::size

unordered_set::max_size

Modifiers

unordered_set::clear

unordered_set::insert

unordered_set::emplace

unordered_set::emplace_hint

unordered_set::erase

unordered_set::swap

unordered_set::extract (C++17)

unordered_set::merge (C++17)

Lookup

unordered_set::count

unordered_set::find

unordered_set::equal_range

Bucket interface

unordered_set::begin(int)

unordered_set::end(int)

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

 

template <class... Args> iterator emplace_hint( const_iterator hint, Args&&... args );		(since C++11)

Inserts a new element to the container, using hint as a suggestion where the element should go. The element is constructed in-place, i.e. no copy or move operations are performed.

The constructor of the element is called with exactly the same arguments as supplied to the function, forwarded with std::forward<Args>(args)....

If rehashing occurs due to the insertion, all iterators are invalidated. Otherwise iterators are not affected. References are not invalidated. Rehashing occurs only if the new number of elements is greater than max_load_factor()*bucket_count().

Parameters

hint	-	iterator, used as a suggestion as to where to insert the new element
args	-	arguments to forward to the constructor of the element

Return value

Returns an iterator to the newly inserted element.

If the insertion failed because the element already exists, returns an iterator to the already existing element with the equivalent key.

Exceptions

If an exception is thrown by any operation, this function has no effect (strong exception guarantee).

Complexity

Amortized constant on average, worst case linear in the size of the container.

See also

emplace	constructs element in-place (public member function)
insert	inserts elements or nodes (since C++17) (public member function)