class apple{
public:
    apple() { std::cout << "CA\n"; }
    virtual ~apple() {std::cout << "DA\n";}
    virtual void show() {std::cout << "apple\n";}
};

class orangeapple: public apple {
public:
    virtual ~orangeapple() { std::cout << "DOA\n"; }
    virtual void show(int count = 2) { std::cout << "2 orangeapples\n"; }
};

class shop {
public:
    void show(apple& p) { std::cout << "shop - "; p.show(); }
    void show(orangeapple& p) { std::cout << "tropic shop - "; p.show(); }
};

int solve()
{
    shop* s = new shop();
    orangeapple oa;
    oa.show();
    orangeapple* poa = &oa;
    apple* a = dynamic_cast<apple*>(poa);
    s->show(oa);
    s->show(*poa);
    s->show(*a);
    delete s;
    return 0;
}


/*
Output:
CA
2 orangeapples
tropic shop - 2 orangeapples
tropic shop - 2 orangeapples
shop - apple
DOA
DA
*/