std::map::at

 

C++

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Regular expressions library (C++11)

Atomic operations library (C++11)

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Containers library

array (C++11)

vector

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list

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unordered_multimap (C++11)

stack

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std::map

Member functions

map::map

map::~map

map::operator=

map::get_allocator

Element access

map::at

map::operator[]

Iterators

map::begin map::cbegin (C++11)

map::end map::cend (C++11)

map::rbegin map::crbegin (C++11)

map::rend map::crend (C++11)

Capacity

map::empty

map::size

map::max_size

Modifiers

map::clear

map::insert

map::emplace (C++11)

map::emplace_hint (C++11)

map::erase

map::swap

Lookup

map::count

map::find

map::equal_range

map::lower_bound

map::upper_bound

Observers

map::key_comp

map::value_comp

 

T& at( const Key& key );	(1)	(since C++11)
const T & at( const Key& key ) const;	(2)	(since C++11)

Returns a reference to the mapped value of the element with key equivalent to key. If no such element exist, 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 key key

Complexity

Logarithmic in the size of the container.

See also

operator[]	access specified element (public member function)