#include <iostream>

class A
{
public:
    virtual ~A() = default;
    virtual int fun(int = 0, float = 5.4f) = 0;
};

class B: public A
{
public:
    int fun(int i = 8, float k = 4.5f) override // You may change default values
                                                // but not recommended
    {
    	std::cout << "fun(i = " << i << ", k = " << k << ")\n";
        return 0;
    }
    int fun(int i, float k, char c) // it is not an override
    {
    	std::cout << "fun(i = " << i << ", k = " << k << ", c = "<< c << ")";
        if(c != 'g') {
        	std::cout << " -> ";
            return fun(i, k);
        } else {
        	std::cout << std::endl;
            return -1;
        }
    }
};

int main() {
	B b;
	A& a = b;
	
	a.fun(); // fun(0, 5.4)
	b.fun(); // fun(8, 4.5) // That part may surprise user
	
	a.fun(-1, 10.5f); // fun(-1, 10.5f)
	
	
	b.fun(42, 4.2f, 'g'); // fun(42, 4.2, g)
	b.fun(420, 6.9f, 'f'); // fun(420, 6.9, f) -> fun(420, 6.9)
}

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