std::deque::front

 

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array (C++11)

vector

deque

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list

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std :: deque

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.

deque::deque

deque::~deque

deque::operator=

deque::assign

deque::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.

deque::front

deque::back

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.

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

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

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

deque::rend deque::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.

deque::empty

deque::size

deque::max_size

deque::shrink_to_fit

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.

deque::clear

deque::insert

deque::emplace

deque::erase

deque::push_front

deque::emplace_front

deque::pop_front

deque::push_back

deque::emplace_back

deque::pop_back

deque::resize

deque::swap

 

reference front();
const_reference front()const;

Devolve uma referência para o primeiro elemento no contentor.

Original:

Returns a reference to the first element in the container.

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Chamando front em um recipiente vazio é indefinido.

Original:

Calling front on an empty container is undefined.

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Parâmetros

(Nenhum)

Original:

(none)

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Valor de retorno

a referência ao primeiro elemento

Original:

reference to the first element

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Complexidade

Constante

Original:

Constant

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Notas

Para uma c recipiente, o c.front() expressão é equivalente a *c.begin().

Original:

For a container c, the expression c.front() is equivalent to *c.begin().

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Exemplo

O código a seguir usa front para exibir o primeiro elemento de um std::deque<char>:

Original:

The following code uses front to display the first element of a std::deque<char>:

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#include <deque>#include <iostream>   int main(){std::deque<char> letters {'o', 'm', 'g', 'w', 't', 'f'};   if(!letters.empty()){std::cout<<"The first character is: "<< letters.front()<<'\n';}}

Saída:

The first character is o

See also

back	access the last element (função pública membro)