std::vector::front

 

C++

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std::vector

Membri funzioni 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

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Elemento accesso 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)

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

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

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

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Capacità 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

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reference front();
const_reference front()const;

Restituisce un riferimento al primo elemento nel contenitore.

Original:

Returns a reference to the first element in the container.

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Chiamare front su un contenitore vuoto non è definito.

Original:

Calling front on an empty container is undefined.

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Parametri

(Nessuno)

Original:

(none)

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Valore di ritorno

riferimento al primo elemento

Original:

reference to the first element

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Complessità

Constant

Original:

Constant

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Note

Per un c contenitore, il c.front() espressione è equivalente a *c.begin().

Original:

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

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Esempio

Il codice seguente utilizza front per visualizzare il primo elemento di un std::vector<char>:

Original:

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

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

Output:

The first character is o

See also

back	access the last element (metodo pubblico)