#include <iostream>
struct R2{
    double x;
    double y;
    R2(double x_, double y_){
        x = x_; y = y_;
    }
    R2(){x = 0; y = 0;}
};
R2 operator+(R2 a, R2 b){
    R2 r;
    r.x = a.x + b.x;
    r.y = a.y + b.y;
    return r;
}
int main(){
    R2 a(1, 1.5), b(1, 2.5), c, d;
    c = a + b;
    d = R2(1, 1) + R2(-1, 5) + a;
    std::cout << c.x << ", " << c.y << ", " << d.x << ", " << d.y << "\n";
    return 0;
}