/**
* Created by rabbit on 2014-07-10.
*/
abstract class student
{
    public abstract void study();
    public abstract void sleep();

}
class Basestudent extends student
{
    public void study()
    {
        System.out.println("Base study");
    }
    public void sleep()
    {
        System.out.println("坐着睡");
    }
    public void eat()
    {
        System.out.println("坐着吃饭");
    }
}

class Advstudent extends student
{
    public void study()
    {
        System.out.println("Adv study");
    }
    public void sleep()
    {
        System.out.println("躺着睡");
    }
}

class Dostudent
{
    public void doSome(student stu)
    {
        stu.study();
        stu.sleep();
    }
}
public class DuoTaiDemo
{
    public static void main(String [] args)
    {
        Dostudent ds = new Dostudent();
        ds.doSome(new Basestudent());
        ds.doSome(new Advstudent());
    }

}