How to Solve the Diamond Problem in OOP Inheritance?

The Diamond Problem is a common issue in object-oriented programming when a class inherits from two or more classes that have a common ancestor. To resolve this problem, you can use virtual inheritance or interfaces.

Diagram:

   A
  / \
 B   C
  \ /
   D

Examples:

1. Using Virtual Inheritance in C++:

   class A {
   public:
       int value = 10;
   };
   
   class B : virtual public A { };
   class C : virtual public A { };
   
   class D : public B, public C { };
   

2. Using Interfaces (in C#):

   interface ICommon {
       void CommonMethod();
   }
   
   class A : ICommon {
       public void CommonMethod() {
           // Implementation
       }
   }
   
   class B : ICommon {
       public void CommonMethod() {
           // Implementation
       }
   }
   
   class D : ICommon {
       public void CommonMethod() {
           // Implementation
       }
   }