std::copy_backward — cppreference.com

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Déclaré dans l'en-tête `<algorithm>`
`template< class BidirIt1, class BidirIt2 > BidirIt2 copy_backward( BidirIt1 first, BidirIt1 last, BidirIt2 d_last );`

Copie les éléments de la gamme, définie par [first, last), à une autre plage qui se termine à d_last. Les éléments sont copiés dans l'ordre inverse (le dernier élément est copié d'abord), mais leur ordre relatif est préservé .

Original:

Copies the elements from the range, defined by [first, last), to another range ending at d_last. The elements are copied in reverse order (the last element is copied first), but their relative order is preserved.

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Paramètres

first, last	-	l'intervalle des éléments à copier Original: the range of the elements to copy The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
d_last	-	fin de la plage de destination. Si `d_last` est dans `[first, last)`, std::copy doit être utilisé à la place de std::copy_backward . Original: end of the destination range. If `d_last` is within `[first, last)`, std::copy must be used instead of std::copy_backward. The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
Type requirements
-`BidirIt` must meet the requirements of `BidirectionalIterator`.

Retourne la valeur

itérateur sur le dernier élément copié .

Original:

iterator to the last element copied.

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Complexité

Exactement last - first missions .

Original:

Exactly last - first assignments.

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Mise en œuvre possible

template< class BidirIt1, class BidirIt2 >
BidirIt2 copy_backward(BidirIt1 first, BidirIt1 last, BidirIt2 d_last)
{
    while (first != last) {
        *(--d_last) = *(--last);
    }
    return d_last;
}

Exemple

#include <algorithm>
#include <iostream>
 
int main()
{
    std::vector<int> from_vector;
    for (int i = 0; i < 10; i++) {
        from_vector.push_back(i);
    }
 
    std::vector<int> to_vector(15);
 
    std::copy_backward(from_vector.begin(), from_vector.end(), to_vector.end());
 
    std::cout << "to_vector contains: ";
    for (unsigned int i = 0; i < to_vector.size(); i++) {
        std::cout << to_vector[i] << " ";
    }
 }

Résultat :

to_vector contains: 0 0 0 0 0 0 1 2 3 4 5 6 7 8 9

Voir aussi


	Copie une série d'éléments vers un nouvel emplacement Original: copies a range of elements to a new location The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (fonction générique) [edit]