#ifndef Number_SEEN__
#define Number_SEEN__
///////    Number.h    ///////
#define OP operator
#define VT virtual
#define CS const

class Number
{  public:
      Number() {}
      Number(int a);
      Number(int a, int b);
      Number(CS Number&);        // copy constructor
      Number& OP =(CS Number&);  // assignment
      VT void display() { ptr->display(); }
      VT Number OP +(CS Number& n) CS
      {   return ptr->OP +(n);  }
      VT Number OP *(CS Number& n) CS
      {   return ptr->OP *(n);  }
      VT Number OP /(CS Number& n) CS
      {   return ptr->OP /(n);  }
      ~Number(){ delete ptr; }
   protected:
      VT Number AddFra(CS Number& n) CS  // n is Fra
      {   return n.ptr->AddFra(*this);  }
      VT Number TimFra(CS Number& n) CS  // n is Fra
      {   return n.ptr->TimFra(*this);  }
      VT Number DivFra(CS Number& n) CS  // n is Fra
      {   return n.ptr->DivFra(*this);  }      // n / *this
      VT Number AddInt(CS Number& n) CS  // n is Int
      {   return n.ptr->AddInt(*this);  }
      VT Number TimInt(CS Number& n) CS  // n is Int
      {   return n.ptr->TimInt(*this);  }
      VT Number DivInt(CS Number& n) CS  // n is Int
      {   return n.ptr->DivInt(*this);  }      // n / *this
   private:
      VT Number* copy() const
      {  return ptr->copy() ;}
      Number* ptr;
};

#include "Fraction.h"
#include "Integer.h"

inline Number::Number(int a)         // make integer
: ptr(new Integer(a)) { }

inline Number::Number(CS Number& n)
: ptr((&n)->copy()) { }
#endif