继承训练

package day07;
class Fu 
{ 
    int num =9;
  Fu()
  {
    System.out.println("fu run"+num);
      
  }
  Fu(int x)
  {
      x=3;
      System.out.println("fu run "+x);
      
  }
  
}
class Zi1 extends Fu
{

    Zi1() {
         System.out.println("Zi1 run");
     
    }
    Zi1(int num)
    {   this();//调用本类构造函数
        System.out.println("Zi1 run"+num);
        
    }
    
}
public class Zi   {
     
    public static void main(String[] args) {
        
          Fu f = new Zi1(6);
          Zi1 z = new Zi1(6);
          
          
        
    }
 
}

fu run9
Zi1 run
Zi1 run6
fu run9
Zi1 run
Zi1 run6