std::map::operator[]

 

C++

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Feature test macros (C++20)

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Especificações Técnicas

Índice de symbolos

Bibliotecas externas

 

Recipientes biblioteca

array (C++11)

vector

deque

forward_list (C++11)

list

set

multiset

map

multimap

unordered_set (C++11)

unordered_multiset (C++11)

unordered_map (C++11)

unordered_multimap (C++11)

stack

queue

priority_queue

 

std::map

Funções de membro Original: Member functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

map::map

map::~map

map::operator=

map::get_allocator

acesso. Elemento Original: Element access The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

map::at

map::operator[]

Iteradores Original: Iterators The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

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

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

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

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

Capacidade Original: Capacity The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

map::empty

map::size

map::max_size

Modificadores Original: Modifiers The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

map::clear

map::insert

map::emplace (C++11)

map::emplace_hint (C++11)

map::erase

map::swap

Pesquisa Original: Lookup The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

map::count

map::find

map::equal_range

map::lower_bound

map::upper_bound

Observadores Original: Observers The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

map::key_comp

map::value_comp

 

T& operator[](const Key& key );	(1)
T& operator[]( Key&& key );	(2)	(desde C++11)

Insere um novo elemento para o recipiente utilizando key como a chave padrão e valor calculado mapeada e retorna uma referência para o valor recém-construído mapeados. Se um elemento com key chave já existe, não é realizada de inserção e uma referência ao seu valor mapeado é devolvido.

Original:

Inserts a new element to the container using key as the key and default constructed mapped value and returns a reference to the newly constructed mapped value. If an element with key key already exists, no insertion is performed and a reference to its mapped value is returned.

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1)

Executa essencialmente (insert(std::make_pair(key, T())).first)->second.

Original:

Essentially performs (insert(std::make_pair(key, T())).first)->second.

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2)

Executa essencialmente (insert(std::make_pair(std::move(key), T())).first)->second.

Original:

Essentially performs (insert(std::make_pair(std::move(key), T())).first)->second.

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No iterators or references are invalidated.

Parâmetros

key

-

a chave do elemento de encontrar Original: the key of the element to find The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

Valor de retorno

Referência ao valor mapeada do elemento novo se nenhum elemento com chave key existiu. Caso contrário, uma referência ao valor do elemento mapeada existente é retornado.

Original:

Reference to the mapped value of the new element if no element with key key existed. Otherwise a reference to the mapped value of the existing element is returned.

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Complexidade

Logarithmic in the size of the container.

Veja também

at (C++11)	acessar o elemento especificado com verificação de limites Original: access specified element with bounds checking The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (função pública membro)