super

class Father
{
public int num = 10;
}
class Son extends Father
{
public int num = 20;
public void show(){
int num = 30;
System.out.println(num);
System.out.println(this.num);//调用本类的成员变量
System.out.println(super.num);//调用父类的成员变量
}
}
class lll
{
public static void main(String[] args){
Son s =new Son();
s.show();
}
}