к реферату

//h
#pragma once

class Figure
{
public:
    virtual void Show() = 0;
    virtual double Square() = 0;
    virtual double Perimeter() = 0;
};

class Rectangle: public Figure
{
protected:
     double a;
     double b;
 public:
    Rectangle();
    Rectangle(double x, double y);
    void Show();
    double Square();
    double Perimeter();
};

class Circle: public Figure
{
protected:
    double r;
public:
    Circle();
    Circle(double x);
    void Show();
    double Square();
    double Perimeter();
};

class Triangle: public Figure
{
protected:
    double a;
    double b;
    double c;
public:
    Triangle();
    Triangle(double x, double y, double z);
    void Show();
    double Square();
    double Perimeter();
};
//cpp
#include "Figure.h"
#include <iostream>


using namespace std;


Rectangle:: Rectangle(): a(0), b(0)
{
}

Rectangle::Rectangle(double x, double y): a(x), b(y)
{
}

void Rectangle::Show()
{
    cout << "the length of the rectangle is: " << a << endl;
    cout << "the width of the rectangle is: " << b << endl;
}

double Rectangle:: Square()
{
    return a * b;
}

double Rectangle::Perimeter()
{
    return a + b;
}


Circle::Circle(): r(0)
{
}

Circle::Circle(double x): r(x)
{
}

void Circle::Show()
{
    cout <<"Radius circle is: " << r << endl;
}

double Circle::Square()
{
    double pi = 3.14;
    return r * r * pi;
}

double Circle::Perimeter()
{
    double pi = 3.14;
    return 2 * pi * r;
}


Triangle::Triangle(): a(0), b(0), c(0)
{
}

Triangle::Triangle(double x, double y, double z): a(x), b(y), c(z)
{
}

void Triangle::Show()
{
    cout << "Sides of the triangle are: " << a << ", " << b << ", " << c << endl;
}

double Triangle::Square()
{
    double p = (a + b + c)/2;
    return sqrt( p * (p - a) * (p - b) * (p - c));
}

double Triangle::Perimeter()
{
    return a + b + c;
}
//main
#pragma once
#include <iostream>
#include "Figure.h"

using namespace std;

int main()
{
    Figure *figures [9];
    figures[0] = new Rectangle (2, 5);
    figures[1] = new Circle (2);
    figures[2] = new Circle (10);
    figures[3] = new Rectangle (12.5, 7);
    figures[4] = new Circle (25);
    figures[5] = new Rectangle (6, 43);
    figures[6] = new Triangle (9, 5, 9);
    figures[7] = new Triangle (3, 4, 5);
    figures[8] = new Triangle (28, 29, 50);
    for(int i = 0; i < 9; i++)
    {
        figures[i] -> Show();
        cout << "Square of figure is: " << figures[i] -> Square() << endl
            << "Peremeter of figure is: " << figures[i] -> Perimeter() << endl << endl;
    }
    for(int i = 0; i < 9; i++)
    {
        delete figures[i];
    }
    return 0;
}