#include <iostream>
using namespace std;
class A {
 public:
     A() : i(42) {}
     friend ostream& operator<<(ostream &out, A const & c);

 protected:
     int i;

};

ostream& operator<< (ostream &output, const A &dataToPrint)
{
        cout << dataToPrint.i << endl;
        return output;
}

int main()
{
    A a;
    std::cout << a;
}