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std::map::emplace_hint

From cppreference.com
< cpp‎ | container‎ | map
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 type (value_type, that is, std::pair<const Key, T>) is called with exactly the same arguments as supplied to the function, forwarded with std::forward<Args>(args)....

No iterators or references are invalidated.

Contents

[edit] 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

[edit] 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.

[edit] Complexity

Logarithmic in the size of the container in general, but amortized constant if the new element is inserted just before hint.

[edit] See also

(C++11)
constructs element in-place
(public member function) [edit]
inserts elements
(public member function) [edit]