стек

#include<iostream>
#include<fstream>
using namespace std;
class Stack
{
	struct Element
	{
		int inf;
		Element *next;
		Element(int x, Element *p) :inf(x), next(p){}
	};
	Element *head;
public:
	Stack() :head(0){}
	bool Empty()
	{
		return head == 0;
	}
	int Pop()
	{
		if (Empty())
		{
			return 0;
		}
		Element *r = head;
		int i = r->inf;
		head = r->next;
		delete r;
		return i;
	}
	void Push(int data)
	{
		head = new Element(data, head);
	}
	int Top()
	{
		if (Empty())
		{
			return 0;
		}
		else
		{
			return head->inf;
		}
	}
};
int main()
{
	Stack q, w;
	int i;
	ifstream in("in.txt");
	ofstream out("out.txt");
	for (int i = 0; in >> i;i++)
	{
		if (i == 9)
		q.Push(i);
		else i++;
	}
	in.close();
	while (!q.Empty())
	{
		out << q.Pop() << " ";
	}
	return 0;
}