#pragma once
#include <cmath>
#include <cstring>

using namespace std;

class Vector2d
{
private:
    double x, y;
public:
    Vector2d();
    Vector2d(double, double);
    Vector2d(double, double, double, double);
    Vector2d(const Vector2d &);
    Vector2d operator+(const Vector2d & ) const;
    Vector2d operator-(const Vector2d & ) const;
    Vector2d operator*(const Vector2d & ) const;
    friend Vector2d operator*(double, Vector2d & );
    Vector2d& operator++();
    Vector2d operator++(int);
    Vector2d& operator--();
    Vector2d operator--(int);
    const Vector2d& operator += (const Vector2d &);
    const Vector2d& operator -= (const Vector2d &);
    const Vector2d& operator *= (const Vector2d &);
    operator string() const;
    void setX(double value)
    {
        x = value;
    }

    double getX()
    {
        return x;
    }

    void setY(double value)
    {
        y = value;
    }

    double getY()
    {
        return y;
    }

    void print(void);
    void sum(Vector2d);
    void sub(Vector2d);
    void mult(double);
    double scalarMult(Vector2d);
    ~Vector2d();
};