The following code example is taken from the book
C++ Templates - The Complete Guide, 2nd Edition
by David Vandevoorde, Nicolai M. Josuttis, and Douglas Gregor,
Addison-Wesley, 2017
© Copyright David Vandevoorde, Nicolai M. Josuttis, Douglas Gregor 2017
#ifndef COORD_HPP
#define COORD_HPP
#include <cstdlib>
class Coord {
private:
int x, y;
public:
Coord (int i1, int i2) : x(i1), y(i2) {
}
friend Coord operator- (Coord const& c1, Coord const& c2) {
return Coord(c1.x-c2.x, c1.y-c2.y);
}
Coord abs() {
return Coord(std::abs(x),std::abs(y));
}
};
#endif // COORD_HPP