Design polygon abstract class with 2 data members : area and perimeter with pure virtual functions. inherit polygon class in 3 classes: Rectangle, Triangle and Square in c++

 Source code:

#include<iostream>

#include<cmath>

#include<iomanip>

using namespace std;

 

class polygon

{protected:

    double area;

    double perimeter;

    virtual void calcarea()=0;

    virtual void calcperi()=0;

public:

    polygon(){

    }

    void printarea()

    {cout<<"area of figure is : "<<area<<endl;

    }

    void printperi()

    {cout<<"perimeter of figure is : "<<perimeter<<endl;

    }

};

class rectangle:public polygon

{public:

    double length;

    double breadth;

    rectangle(double l,double b){length=l;

    breadth = b;

    }

    void calcarea()

    {

    cout<<"area is "<<length*breadth;

    }

    void calcperi()

    {

    cout<<"perimeter is "<<(length+breadth)*2;

    }

};

class square : public polygon

{public:

    double side;

    square(double s){side = s;}

    void calcarea(){

        cout<<"Area is : "<<side*side<<endl;

    }

    void calcperi(){

        cout<<"perimeter is : "<<4*side<<endl;

    }

};

 

class triangle:public polygon

{public:

    double side_a;

    double side_b;

    double side_c;

    triangle(double a,double b,double c ){side_a = a;

    side_b = b, side_c = c;

    }

    void calcarea()

    {

        float s=(side_a+side_b+side_c)/2;

    cout<<"area is "<<sqrt(s*(s-side_a)*(s-side_b)*(s-side_c));

    }

    void calcperi()

    {

    cout<<"perimeter is "<<(side_a=side_b=side_c)*2;

    }

};

 

int main()

{rectangle s1(16,4);

square s2(6);

triangle s3(88,55,99);

 

cout<<"for rectangle: "<<endl;

s1.calcarea();

cout<<endl;

s1.calcperi();

cout<<endl;

cout<<"for square : "<<endl;

s2.calcarea();

s2.calcperi();

cout<<"for triangle: "<<endl;

s3.calcarea();

cout<<endl;

s3.calcperi();

cout<<endl;

 

return 0;

}