Answer: When we declare/write a class, there is no memory allocation happens for data members of a class, so, we cannot store data into data members.
The memory gets allocated for data members only when we create objects of a class. So, initialization of the variable happens once object of the class get created.
Example:
In the below example, initialization of data member int a=2; cannot be done at the time of declaration.
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class A{ // int a=2; // compiler error,member variable can’t be initialized here int b; //ok public: A(int _b){ this->b =_b; cout<<"Object b initialized with value :"<b; } }; int main() { A obj(5);// initialize the object return 0; } |