layla

#include <iostream>
#include <string>
#include <iomanip>
#include <fstream>
#include <clocale>
#include <curses.h>
#include <cstdlib>
#include <cstdio>

using namespace std;

class dvect2 {
protected:
    double x;
    double *py;

public:
    dvect2() // конструктор без параметров
    {
        py = new double(0);
    }

    ~dvect2() {
        if (py != NULL)
            delete py;
    }

    dvect2(dvect2 &z) //конструктор копирования
    {
        x = z.x;
        py = new double(*z.py);
    }

    dvect2(double x0, double y0) //конструктор с параметрами
    {
        x = x0;
        py = new double(y0);
    }

    friend istream &operator>>(istream &in, dvect2 &z);

    void raz(dvect2 v1, dvect2 v2);

    dvect2 &operator=(dvect2 &z) //перегрузка присваивания
    {
        if (this == &z)
            return z;
        x = z.x;
        *py = *z.py;
        return *this;
    }
};


istream &operator>>(istream &in, dvect2 &z) {
    cout << "x = ";
    in >> z.x;
    cout << "y = ";
    in >> *z.py;
    return in;
}

void dvect2::raz(dvect2 v1, dvect2 v2) {
    x = v1.x - v2.x;
    *py = *v1.py - *v2.py;
}

class vect3 : public dvect2 {
private:
    double z;
public:
    vect3() : dvect2() {}

    vect3(double x0, double y0, double z0) : dvect2(x0, y0), z(z0) {}

    ~vect3() {
        dvect2::~dvect2();
    }

    vect3(vect3 &z1) : dvect2(z1) {
        z = z1.z;
    }

    vect3 &operator=(vect3 &z1) {
        if (this == &z1)
            return z1;
        dvect2::operator=(z1);
        z = z1.z;
    }

    friend istream &operator>>(istream &in, vect3 &z1);

    void razn(vect3 v1, vect3 v2);

};

istream &operator>>(istream &in, vect3 &z1) {
    cout << "x = ";
    in >> z1.x;
    cout << "y = ";
    in >> *z1.py;
    cout << "z = ";
    in >> z1.z;
    return in;
}

void vect3::razn(vect3 v1, vect3 v2) {
    x = v1.x - v2.x;
    *py = *v1.py - *v2.py;
    z = v1.z - v2.z;
}