how many vtable the compliler will be created in multi-level inheritance

class Base
 {
 public:
    virtual void function1() {cout<<"Base :: function1()\n";};
    virtual void function2() {cout<<"Base :: function2()\n";};
    virtual ~Base(){};
};

class D1: public Base
{
public:
   ~D1(){};
   virtual void function1() { cout<<"D1 :: function1()\n";};
};

class D2: public Base
{
public:
   ~D2(){};
   virtual void function2() { cout<< "D2 :: function2\n";};
};

int main()
{
  D1 *d = new D1;;
  Base *b = d;

  b->function1();
  b->function2();

  delete (b);

  return (0);
}