std::unordered_set::emplace_hint

 

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std::unordered_set

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unordered_set::unordered_set

unordered_set::~unordered_set

unordered_set::operator=

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unordered_set::begin unordered_set::cbegin

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unordered_set::clear

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unordered_set::emplace

unordered_set::emplace_hint

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unordered_set::count

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unordered_set::begin2

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unordered_set::bucket

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unordered_set::load_factor

unordered_set::max_load_factor

unordered_set::rehash

unordered_set::reserve

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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 higher 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.

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 (public member function)