// Classes have methods and data.  The data is nearly always private.
// A class really should have some public methods to be useful,
// (say, a constructor) but private methods, used internally, are also common.

#include <iostream>

using namespace std;

class Point {
  public:
    Point(int a, int b) { x = a; y = b; }   // constructor (alias ctor)
    int get_x() const { return x; }	    // accessor
    int get_y() const { return y; }	    // accessor
    void go_right() { x++; }		    // mutator
  private:
    int x, y;				    // Hands off!
};

// Make << work for a Point.
ostream& operator<<(ostream &out, const Point &p) {
    return out << p.get_x() << ',' << p.get_y();
    // Hey!  How can we return an output statement!?
}

int main() {
    Point p(19,57);	// Parameters to ctor
    // p.x = 5;		// Sorry, it’s private!
    cout << p << '\n';	// invoke overloaded <<, as defined above
    p.go_right();
    cout << p << '\n';
    return 0;		// dtor (where is it?) called automatically
}