std::vector::empty

 

C++

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std::vector

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.

vector::vector

vector::~vector

vector::operator=

vector::assign

vector::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.

vector::at

vector::operator[]

vector::front

vector::back

vector::data (C++11)

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.

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

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

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

vector::rend vector::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.

vector::empty

vector::size

vector::max_size

vector::reserve

vector::capacity

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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::vector<int> contém quaisquer elementos:

Original:

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

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#include <vector>#include <iostream>   int main(){std::vector<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)