class Outer {

public:
   class Inner;
 void getParams(std::string &str1, std::string &str2);
 explicit Outer(const std::string &fullName = "", const std::string &version = "");
 void addition(int b, int c);
 void subtraction(int b, int c);
private:
 Inner *m_d;
 const Inner *d_func() const {return m_d;}
 Inner *d_func() {return m_d;}
};

class Callback;

class Outer::Inner {

public:
   friend class Callback;
   void getParams(std::string &str1, std::string &str2);
   void division(int b, int c);
   Inner(const std::string &fullName, const std::string &version);
private:
   Callback *innerReciever;

};

class CallbackVirtual {
public:
   virtual void sendParameters(std::string &str1, std::string &str2) = 0;

};


class Callback : public Outer {
public:
   void sendParameters(std::string &str1, std::string &str2);
};

Outer::Outer(const std::string &fullName, const std::string &version) :
   m_d(new Inner(fullName, version)) {

}

Outer::Inner::Inner(const std::string &fullName, const std::string…