std::copy_n

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Defined in header <algorithm>

template< class InputIterator, class Size, class OutputIterator>
OutputIterator copy_n(InputIterator first, Size count, OutputIterator result);

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

Contents

[edit] Parameters

first - the beginning of the range of elements to copy from
count - number of the elements to copy
result - the beginning of the destination range

[edit] Return value

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

[edit] Complexity

Exactly count assignments, if count>0.

[edit] Equivalent function

[edit] Example

#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

[edit] See also

copy
copy_if

(C++11)
copies a range of elements to a new location
(function template)