C++ Series - Interview questions

How to prevent a class from inheritance ?

) Private Constructor(s)

class CBase 

{ public: 

static CBase* CreateInstance()  

{  

  CBase* b1 = new CBase(); 

  return b1; 

 } 

private: 

 CBase() { } 

 CBase(CBase3) { } 

 CBase& operator=(CBase&) { } 

}; 

2) Using CSealed base class, private ctor & virtual inheritance

class CSealed 

{ private: 

 CSealed() { 

 } 

 friend class CBase; 

}; 

class CBase : virtual CSealed 

{ 

 public: 

 CBase() { 

 } 

 }; 

3) Using a CSealed base class, protected ctor & virtual inheritance

class CSealed 

{ 

 protected: 

 CSealed() { 

 } 

}; 

 class CBase : virtual CSealed 

{ 

public: 

CBase() { } 

};