NAME¶

std::map::at - std::map::at

Synopsis¶

T& at( const Key& key ); (1)
const T& at( const Key& key ) const; (2)

Returns a reference to the mapped value of the element with key equivalent to key.
If no such element exists, an exception of type std::out_of_range is thrown.

Parameters¶

key - the key of the element to find

Return value¶

Reference to the mapped value of the requested element

Exceptions¶

std::out_of_range if the container does not have an element with the specified key

Complexity¶

Logarithmic in the size of the container.

Defect reports

The following behavior-changing defect reports were applied retroactively to
previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 464 C++98 map did not have this member function added

See also¶

operator[] access or insert specified element
(public member function)