std::vector::front

 

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std::vector

Las funciones miembro 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.

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Elemento acceso 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.

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reference front();
const_reference front() const;

Devuelve una referencia al primer elemento en el recipiente .

Original:

Returns a reference to the first element in the container.

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Llamar a front en un recipiente vacío es indefinido .

Original:

Calling front on an empty container is undefined.

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Parámetros

(Ninguno)

Original:

(none)

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Valor de retorno

referencia al primer elemento

Original:

reference to the first element

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Complejidad

Constant

Original:

Constant

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Notas

Para una c contenedor, el c.front() expresión es equivalente a *c.begin() .

Original:

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

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Ejemplo

El código siguiente utiliza front para mostrar el primer elemento de una 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';
    }  
}

Salida:

The first character is o

See also

back	accede al último elemento Original: access the last element The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (función miembro público)