#include <vector>
#include <string>
#include <iostream>
#include <deque>
#include <list>

using std::cout;
using std::cin;
using std::cerr;
using std::endl;
using std::string;
using std::vector;
using std::list;

int main()
{
	vector<int> ivec = { 5, 6, 7, 8, 9 };

	double cnt = ivec.size() / 2.0;

	int i = 0;

	while (cnt > 0)
	{
		ivec.insert(ivec.begin(), i--);
		--cnt;
	}

	for (auto &i : ivec)
		cout << i << " ";

	cout << endl;

	system("pause");

	return 0;
}