class Stack {
	int stcksize = 100;
	int stck[] = new int[stcksize];
	int tos;

	Stack() {
		tos = -1;
	}

	void push(int item) {
		if (tos == stcksize - 1)
			System.out.println("Stack Overflow");
		else
			stck[++tos] = item;
	}

	int pop() {
		if (tos < 0) {
			System.out.println("Stack Underflow.");
			return 0;
		} else
			return stck[tos--];
	}
}

public class UseStack {
	public static void main(String args[]) {
		Stack s = new Stack();
		s.push(1);
		s.push(2);
		s.push(3);
		s.pop(); // return 3 as it was the last inserted element
	}
}