std::copy_n

 

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Funciones Original: Functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
Para no modificar la secuencia de las operaciones Original: Non-modifying sequence operations The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
all_of any_of none_of (C++11) (C++11) (C++11) for_each count count_if mismatch equal	find find_if find_if_not (C++11) find_end find_first_of adjacent_find search search_n
Modificación de la secuencia de operaciones Original: Modifying sequence operations The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
copy copy_if (C++11) copy_n (C++11) copy_backward move (C++11) move_backward (C++11) fill fill_n transform generate generate_n remove remove_if remove_copy remove_copy_if	replace replace_if replace_copy replace_copy_if swap swap_ranges iter_swap reverse reverse_copy rotate rotate_copy random_shuffle shuffle   (C++11) unique unique_copy
Particionamiento operaciones Original: Partitioning operations The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
is_partitioned (C++11) partition partition_copy (C++11)	stable_partition partition_point (C++11)
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is_sorted (C++11) is_sorted_until (C++11) sort	partial_sort partial_sort_copy stable_sort nth_element
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merge inplace_merge includes	set_difference set_intersection set_symmetric_difference set_union
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max max_element min min_element minmax (C++11) minmax_element (C++11)	lexicographical_compare is_permutation (C++11) next_permutation prev_permutation
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Defined in header <algorithm>
template< class InputIt, class Size, class OutputIt > OutputIt copy_n( InputIt first, Size count, OutputIt result );

Copies exactly count values from the range beginning at first to the range beginning at result, if count>0. Does nothing otherwise.

Parámetros

first	-	the beginning of the range of elements to copy from
count	-	number of the elements to copy
result	-	el comienzo del rango de destino Original: the beginning of the destination range The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
Type requirements
- InputIt must meet the requirements of InputIterator.
- OutputIt must meet the requirements of OutputIterator.

Valor de retorno

Iterator in the destination range, pointing past the last element copied if count>0 or first otherwise.

Complejidad

Exactly count assignments, if count>0.

Posible implementación

template< class InputIt, class Size, class OutputIt> OutputIt copy_n(InputIt first, Size count, OutputIt result) { if (count > 0) { *result++ = *first; for (Size i = 1; i < count; ++i) { *result++ = *++first; } } return result; }

Ejemplo

#include <iostream>
#include <string>
#include <algorithm>
#include <iterator>
 
int main()
{
    std::string in = "1234567890";
    std::string out;
 
    std::copy_n(in.begin(), 4, std::back_inserter(out));
    std::cout << out << '\n';
}

Output:

1234

Ver también

copy copy_if (C++11)	Copia un intervalo de elementos a una nueva ubicación 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. (función de plantilla)