#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;
}

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