why can't we declare object of a class inside the same class?

Question

class A
{
  A a;//why can\'t we do this
};

Answer 1

In C++ : You can not do this, As it will be recursive structure (no end for calculating object size) , to Overcome this problem,
Use Self Referential Pointer i.e. the Pointer having the address of Same class type.

class A
{
    A* aObj; // Self Referential Pointer
}