class A{
class Dog{
private String name;
private int age;
public int step;
Dog(String s,int a)
{
name=s;
age=a;
step=0;
}
public void run(Dog fast)
{
fast.step++;
}
}
public static void main (String args[])
{
A a=new A();
Dog d=a.new Dog("Tom",3);
d.step=25;
d.run(d);
System.out.println(d.step);
}
}