#include <iostream>

using namespace std;

class Figure {
    protected:
        float s;

    public:
        void show() {
            cout << "Info about figure:" << endl;
            calculate();
            info();
        }

        virtual void calculate() = 0;

        virtual void info() = 0;
};

class Rectangle : public Figure {
    private:
        float a;

        float b;

    public:
        Rectangle() {}

        Rectangle(float _a, float _b) : a(_a), b(_b) {}

        void calculate() {
            s = a * b;

            cout << "Area of rectangle = " << s << endl;
            cout << endl;
        }

        void info() {
            cout << "Sides of rectangle:" << endl;
            cout << "\ta = " << a << endl;
            cout << "\tb = " << b << endl;
            cout << endl;
        }

        friend istream& operator >> (istream& is, Rectangle& x);

        bool operator > (const Rectangle& x) { return a > x.a && b > x.b; }
};

class Trapeze : public Figure {
    private:
        float a;

        float b;

        float h;

    public:
        Trapeze() {}

        Trapeze(float _a, float _b, float _h) : a(_a), b(_b), h(_h) {}

        void calculate() {
            s = h * (a + b) / 2;

            cout << "Area of trapeze = " << s << endl;
            cout << endl;
        }

        void info() {
            cout << "Sides of trapeze:" << endl;
            cout << "\ta = " << a << endl;
            cout << "\tb = " << b << endl;
            cout << "\th = " << h << endl;
            cout << endl;
        }

        friend istream& operator >> (istream& is, Trapeze& x);

        bool operator > (const Trapeze& x) { return a > x.a && b > x.b && h > x.h; }
};

istream& operator >> (istream& is, Rectangle& x) {
    cout << "Enter sides of rectangle:" << endl;
    cout << "\ta = "; is >> x.a;
    cout << "\tb = "; is >> x.b;
    cout << endl;

    return is;
}

istream& operator >> (istream& is, Trapeze& x) {
    cout << "Enter sides of trapeze:" << endl;
    cout << "\ta = "; is >> x.a;
    cout << "\tb = "; is >> x.b;
    cout << "\th = "; is >> x.h;
    cout << endl;

    return is;
}

int main() {
    cout << "===Work with arrays===" << endl << endl;

    int n;

    cout << "Enter count of objects:" << endl;
    cin >> n;
    cout << endl;

    Rectangle rectArr[n];

    for (int i = 0; i < n; i++) {
        cout << "Enter info about " << i + 1 << " rectangle:" << endl;
        cin >> rectArr[i];
    }

    for (int i = 1; i < n; i++) {
        cout << "Comparing (operator >) " << i << " & " << i + 1 << " rectangles: "<< endl;
        cout << "result: " << (rectArr[i - 1] > rectArr[i]) << endl;
        cout << endl;
    }

    Trapeze trapzArr[n];

    for (int i = 0; i < n; i++) {
        cout << "Enter info about " << i + 1 << " trapeze:" << endl;
        cin >> trapzArr[i];
    }

    for (int i = 1; i < n; i++) {
        cout << "Comparing (operator >) " << i << " & " << i + 1 << " trapezes: "<< endl;
        cout << "result: " << (trapzArr[i - 1] > trapzArr[i]) << endl;
        cout << endl;
    }

    cout << "===Work using the base class pointer===" << endl << endl;

    Figure* figr = new Rectangle(3, 4);

    figr->show();

    figr = new Trapeze(3, 4, 2);

    figr->show();

    return 0;
}