std::list::empty

 

C++

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array (C++11)

vector

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forward_list (C++11)

list

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std::list

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.

list::list

list::~list

list::operator=

list::assign

list::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.

list::front

list::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.

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

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

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

list::rend list::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.

list::empty

list::size

list::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.

list::clear

list::insert

list::emplace (C++11)

list::erase

list::push_front

list::emplace_front (C++11)

list::pop_front

list::push_back

list::emplace_back (C++11)

list::pop_back

list::resize

list::swap

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

list::merge

list::splice

list::remove list::remove_if

list::reverse

list::unique

list::sort

 

bool empty()const;

Verifica se o recipiente não tem elementos, ou seja, se begin()== end().

Original:

Checks if the container has no elements, i.e. whether begin()== end().

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Parâmetros

(Nenhum)

Original:

(none)

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Valor de retorno

true se o recipiente estiver vazio, false contrário

Original:

true if the container is empty, false otherwise

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Exceções

noexcept specification:  

noexcept

  (desde C++11)

Complexidade

Constante

Original:

Constant

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Exemplo

O código a seguir usa empty para verificar se um std::list<int> contém quaisquer elementos:

Original:

The following code uses empty to check if a std::list<int> contains any elements:

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#include <list>#include <iostream>   int main(){std::list<int> numbers;std::cout<<"Initially, numbers.empty(): "<< numbers.empty()<<'\n';   numbers.push_back(42); numbers.push_back(13317);std::cout<<"After adding elements, numbers.empty(): "<< numbers.empty()<<'\n';}

Saída:

Initially, numbers.empty(): 1 After adding elements, numbers.empty(): 0

See also

size	devolve o número de elementos Original: returns the number of elements 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)