#include <array>
#include <algorithm>
#include <iostream>
 
int main(int argc, char* argv[])
{
    std::array<int, 4> high_numbers;
	{
		std::array<int, 8> some_numbers = { 0, 3, 4, 6, 2, 9, 1, 5 }; // imagine these comme from std::cin
		std::sort(some_numbers.begin(), some_numbers.end());
		std::copy(some_numbers.begin() + some_numbers.size() / 2, some_numbers.end(), high_numbers.begin());
	} // original array disappears just like OP mentioned
 
	std::cout << "Tell me where the damn size changes?" << std::endl;
	std::for_each(high_numbers.begin(), high_numbers.end(), [](int i) { std::cout << i << " "; });
 
	return 0;
}

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