int main(){
Dog dg;
//dg.setName("Mark"); // this will give error coz setName is protected in dog class, and is unaccessable
dg.setDogName("Mark");
dg.show();
return 0;
}
int main(int argc, const char * argv[])
{
//Animal a;//抽象类不能实例化
Dog d;
d.show();
//抽象类虽然不能实例化，但可以用指针指向子类的对象
Animal* a = new Dog();
a->show();
}
