class SuperClass{
	int a=5,b=8,c=85;
	void show(){
	  System.out.println("a*b="+(a*b));
	}
}
class SubClass extends SuperClass{
	int b=26,d=32;
	void show()	{
	  System.out.println("b+d="+(b+d));
	}
}
public class ClassExchangeDemo{
	public static void main(String args[]){
		SuperClass super1,super2;                   //
		SubClass sub1,sub2;                       //
		super1=new SuperClass();
		sub1=new SubClass();
		System.out.println("super1.a="+super1.a+"\tsuper1.b="+super1.b+"\tsuper1.c="+super1.c); 
		super1.show();
		System.out.println("sub1.b="+sub1.b+"\tsub1.c="+sub1.c+"\tsub1.d="+sub1.d);	 
		sub1.show();
		super2=(SuperClass)sub1;                   //תΪ
		System.out.println("super2.a="+super2.a+"\tsuper2.b="+super2.b+"\tsuper2.c="+super2.c);
		System.out.println("super2.show():\t");	
		super2.show();
		sub2=(SubClass)super2; 	              //תΪ
		System.out.println("sub2.a="+sub2.a+"\tsub2.b="+sub2.b+"\tsub2.d="+sub2.d);
		System.out.println("sub2.show():\t");	
		sub2.show();
	}
}
