Why is not overloaded function for derived class object invoked when given a pointer to base class in C++?

Question

In the following code

#include 
using namespace std;

class A {
  public:
    A() {}
    virtual ~A() {};
};

class B : public A {
  public:
             


        

Answer 1

You need to make process() a virtual member function of A, B:

class A {
  public:
    A() {}
    virtual ~A() {};
    virtual void process() const { cout << "processing A" << endl; }
};

class B : public A {
  public:
    B() {}
    virtual ~B() {};
    virtual void process() const override { cout << "processing B" << endl; }
};

int main(void) {
    A* a = new B;
    a->process();
    return 0;
}

In your current code, *a is of type A&, so the closest match to process(*a); is the first overload (for const A&).