#ifndef __v2d__
#define __v2d__

class v2d{
private:
    double x, y;
public:
    // standard constructor
    v2d(double x, double y);

    ~v2d(){};

    // copy constructor
    v2d(const v2d & v);

    // assignment
    v2d & operator=(const v2d &v);

    // vector addition
    v2d & operator+(const v2d &v);

    // direct product
    double operator*(const v2d &v);

    // scalar multiplication
    v2d & operator*(double k);

    // length
    double length();

};


#endif