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#include <iostream>

class dpoint {
    double *px;
    double y;
public:
    double getPx() const;

    double getY() const;

    dpoint(double ix, double iy) {
        px = new double(ix);
        y = iy;
    }

/*    dpoint(dpoint &a) {
        px = new double(*a.px);
        y = a.y;
    }*/

    ~dpoint() {
        delete px;
    }

    friend std::istream &operator>>(std::istream &in, dpoint &var) {
        in >> *var.px >> var.y;
        return in;
    }

    friend void increaseCoordinate(dpoint &a, double dx, double dy);

    friend std::ostream &operator<<(std::ostream &os, const dpoint &dpoint1);

    dpoint& operator=(dpoint& a){
        px = new double(*a.px);
        y = a.y;
    }
};


void increaseCoordinate(dpoint &a, double dx, double dy) {
    std::cout << "\n inc " << *a.px << " " << a.y << "\n";
    if (a.px == nullptr) {
        a.px = new double(dx);
    } else
        *a.px += dx;
    a.y += dy;
}

std::ostream &operator<<(std::ostream &os, const dpoint &dpoint1) {
    os << "px: " << *dpoint1.px << " y: " << dpoint1.y;
    return os;
}

double dpoint::getPx() const {
    return *px;
}

double dpoint::getY() const {
    return y;
}

class interval {
    dpoint a;
    dpoint b;
public:

//    interval(const dpoint &a, const dpoint &b) : a(a), b(b) {}
    interval(double ax, double ay, double bx, double by): a(ax,ay), b(bx,by){}
    interval(interval &i2) : a(i2.a.getPx(),i2.a.getY()),b(i2.b.getPx(),i2.b.getY()) {}

    friend void swap(interval &m) {
        dpoint c(m.a.getPx(),m.a.getY());
        m.a = m.b;
        m.b = c;
    }

    void showPoints() {
        std::cout << "xa " << a.getPx() << " ya " << a.getY() << " xb " << b.getPx() << " yb " << b.getY() << "\n";
    }

    friend std::istream &operator>>(std::istream &in, interval& x) {
        in >> x.a >> x.b;
        return in;
    }
};

int main() {
    dpoint t(3.1, 77.9), a(1, 1);
    std::cout << t << "\nВведите 2 точки\n";
    std::cin >> a;
    std::cout << "magic:\n" << a << "\n";
    increaseCoordinate(a, 5.5, 1.1); std::cout << a << "\n-----------\n";

//    interval i1(dpoint(1.1, 2.2), dpoint(3.3, 4.4));
//    interval i1(t, a);
    interval i1(6,7,8,9);
    std::cout << "i1\n";
    i1.showPoints();
    interval i2(i1);
    std::cout << "i2\n";
    i2.showPoints();
    std::cout << "ESHE 4 tochki\n";
    std::cin >> i2;
    std::cout << "i2\n";
    i2.showPoints();
    std::cout << "i1\n";
    i1.showPoints();
    swap(i1);
    std::cout << "i1\n";
    i1.showPoints();

    return 0;
}