How to print out the contents of a std::vector with std::copy_n?

Question

I want to print out the contents of a std::vector in C++.

Here is what I have:

#include <iostream>
#include <iterator>
#include <vector>
#include <algorithm>

using namespace std;

int main()
{
  vector<int> v;
  copy_n(istream_iterator<int>(cin), 5, back_inserter(v));

  return 0;
}

Can I print the contents of the std::vector with the same method?

Answer 1

Yes. You need to iterate through the vector and std::copy the contents to the output stream with the help of std::ostream_iterator .

std::copy(v.begin(), v.end(), std::ostream_iterator<int>(std::cout, " "));

See live

Answer 2

是的，您可以通过将迭代器以及vector和std::ostream_iterator的大小传递给std::copy_n 。

std::copy_n(v.begin(), v.size(), std::ostream_iterator<int>(std::cout, " "));