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std::vector::front — cppreference.com

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reference front();

const_reference front() const;

Renvoie une référence au premier élément dans le conteneur .

Original:

Returns a reference to the first element in the container.

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Appel front sur un contenant vide est indéfini .

Original:

Calling front on an empty container is undefined.

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Paramètres

(Aucun)

Original:

(none)

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Retourne la valeur

référence au premier élément

Original:

reference to the first element

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Complexité

Constante

Original:

Constant

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Notes

Pour une c conteneur, le c.front() expression est équivalente à *c.begin() .

Original:

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

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Exemple

Le code suivant utilise front pour afficher le premier élément d'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';
    }  
}

Résultat :

See also

accède au dernier élément
(fonction membre publique) [edit]