Thread: Overload pre and post increment

Hi all,

I just reached the overloading chapter, amazing and confusing .
so i tried to overload the pre and post increment operations. So i did the following:

Simple class:

Code:

class Counter {
public:
    Counter() : val(0) {};
    Counter(int ival) : val(ival) {};
    Counter(const Counter& rhs);


    int GetVal() const { return val; }
    void SetVal(int v) { val = v; }


    const Counter operator++();
    const Counter operator++(int dummy);
private:
    int val;
};

Pre-increment:

Code:

const Counter Counter::operator++() {
    cout << "pre increment called" << std::endl;
    ++val;
    return *this;
}

Post-increment:

Code:

const Counter Counter::operator++(int dummy) {
    cout << "post increment called" << std::endl;
    Counter temp(*this);
    ++val;
    return temp;
}

using both of them :

Code:

Counter c(1);
Counter pre = ++c;
Counter post = c++;

i printed the results. they are fine and correct.
the 2 functions are similar except the parameter "dummy".
my question : how is ++c or c++ calling the right function ?

why is ++c calling the function without input parameter? and c++ calling the function with the input parameter?