Operator <<

The following program shows how to overload operator <<:

#include <iostream>
using namespace std;

class Test
{
    int x, y;

public:
    Test() : x(0), y(0) {}

    friend void operator << (ostream& out, Test test);
};

void operator << (ostream& out, Test test)
{
    out << "overloaded operator <<" << endl;
    out << "x = " << test.x << endl;
    out << "y = " << test.y << endl;
}

int main()
{
    Test test;
    cout << test;
}