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#include <iostream>
using namespace std;
class Point {
private:
// fields are accessible only to methods belonging to point
double x;
double y;
public:
// constructor accepting two arguments, called by a
// statement such as: Point p(1, 2);
Point(double a_x, double a_y) : x(a_x), y(a_y) {}
// Point::print method defined in base class
// note the use of the virtual keyword below
virtual void print() {
cout << '(' << x << ',' << y << ')' << endl;
}
};
class NamedPoint : public Point {
private:
string name;
public:
// constructor calls point constructor then initializes name
NamedPoint(double x, double y, string name) :
Point(x, y), name(name) {}
// NamedPoint::print method defined in derived class
// note the use of the virtual keyword below
virtual void print() {
cout << name << ' ';
Point::print();
}
};
int main() {
NamedPoint p(0, 0, "origin");
Point &refP = p;
Point *pp = &p;
refP.print(); // dynamic binding calls NamedPoint::print()
pp->print(); // ditto
return 0;
}
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