gistfile1.c++

#include <iostream>

using namespace std;

class A
{
protected:
public:
    int count;

    A() : count(1) {

    };

    void retain() { ++count; }
    
    void release()
    {
        cout << "RELEASE" << endl;
        count--;
        if (count == 0) {
            cout << "COUNT == 0" << endl;
            delete this;
        }
    }

    virtual ~A() { cout << "~A" << endl; }

    void operator delete(void* ptr, size_t s)
    {
        cout << "A" << endl;
    }
};

class B : public A
{
public:

    virtual ~B() { cout << "~B" << endl; }

    void operator delete(void* ptr, size_t s)
    {
        cout << "B" << endl;
    }
};

template<typename T>
class C : public B
{
public:
    virtual ~C() { cout << "~C" << endl; }

    void operator delete(void* ptr, size_t s)
    {		
        A* a = (A *) ptr;
        cout << a->count << endl;
        if (a->count > 1 ) {
            cout << "releasing" << endl;
            a->release();
        } else {
            cout << "C" << sizeof(T) << endl;
        }
    }
};

int main()
{
    B* b = new C<int>;
    b->retain();
    b->release();
    //b->release();
            
    delete b;
}