//接口的繼承
interface Inter1
{
	final int M=234;
	public abstract void f(int x);
	public abstract void g(int x,int y);
}
interface Inter_ extends Inter1
{ 
	public abstract double h(double x);
}
class A1 implements Inter_
{
	public void f(int x)
	{System.out.println("A1,f:"+x);
	}
	public void g(int x,int y)
	{System.out.println("A1,g:"+x+","+y);
	}
	public double h(double x)
	{
		return x/2;
	}
}
class B
{
	void read(Inter_ s)
	{
		s.f(10);
		s.g(10,20);
	System.out.println(s.h(30));
	System.out.println(s.M);	
	}
}
public class Inter
{
	public static void main(String[] args)
	{
		B b=new B();
		b.read(new A1());
	
}
}