/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

public class Main
{
    private String[] s;
    private int N = 3;

    public Main(int capacity)
    { s = new String[capacity]; }

    public boolean isEmpty()
    { return N == 0; }

    public void push(String item)
    { s[N++] = item; }

    public String pop()
    { 
        return s[--N];
    }

    public static void main(String[] args) {
        Main stack = new Main(3);
        System.out.println(stack.pop());
        System.out.println(stack.pop());
        System.out.println(stack.pop());
        System.out.println(stack.isEmpty());
    }
}