virtualFunction.cpp

#include <iostream>
#include <cstring>
using namespace std;

    class twoDShape
    {
        double width, height;
        char name[30];
        public:

        twoDShape()
        {
            height=width=0;
            strcpy(name, "Unknown");
        }

        twoDShape(double i,char *n)
        {
            height=width=i;
            strcpy(name, n);
        }

        twoDShape(double h,double w,char *n)
        {
            height=h;
            width=w;
            strcpy(name, n);
        }

        void showdim()
        {
            cout<<"The width is: "<<width<<" and the Height is: "<<height<<endl;
        }

        virtual double area()=0; // Area() is a pure virtual function

        /* Because twoDshape contains One pure virtual function it has became an 
        Abstract class which can't be instantiated */

        double getheight()
        {
            return height;
        }

        double getwidth()
        {
            return width;
        }

        char *getname()
        {
            return name;
        }

        void setheight(double h)
        {
            height=h;
        }

        void setwidth(double w)
        {
            width=w;
        }
    };

    class triangle: public twoDShape
    {
        char style[30];
        public:

        triangle()
        {
            strcpy(style,"Unknown");
        }

        triangle(char *str, double i): twoDShape(i,"triangle")
        {
            strcpy(style, str);
        }

        triangle(char *str, double h, double w): twoDShape(h,w,"triangle")
        {
            strcpy(style, str);
        }

        void showstyle()
        {
            cout<<"The Triangle is "<<style<<"\n";
        }

        double area()
        {
            return getheight()*getwidth()/2;
        }
    };

    class rectangle: public twoDShape
    {
        public:

        rectangle(double i): twoDShape(i,"rectangle")
        {
           
        }

        rectangle(double h, double w): twoDShape(h,w,"rectangle")
        {
           
        }

        bool isSquare()
        {
            if(getheight()==getwidth())return true;
            return false;
        }

        double area()
        {
            return getheight()*getwidth();
        }
    };

    int main()
    {
        twoDShape *shapes[4];

        double e,r;
        cout<<"Enter 2 numbers for the second Shape dimension"<<endl;
        cin>>e;
        cin>>r;
        char ab[30];
        cout<<"Enter the Style of the Second Shape"<<endl;
        cin>>ab;
        triangle b(ab,e,r);

        double t;
        cout<<"Enter One number for the third Shape dimension"<<endl;
        cin>>t;
        char ad[30];
        cout<<"Enter the Style of the third  Shape"<<endl;
        cin>>ad;
        triangle c(ad,t);

        double y,u;
        cout<<"Enter 2 numbers for the fourth Shape dimension"<<enl;
        cin>>y;
        cin>>u;
        rectangle d(y,u);

        double v;
        cout<<"Enter One number for the fifth Shape dimension"<<endl;
        cin>>v;
        rectangle l(v);

        shapes[0]= &b;
        shapes[1]= &c;
        shapes[2]= &d;
        shapes[3]= &l;

        for(int i=1; i<5; i++)
        {
            cout<<"Object is: " <<shapes[i]->getname()<<endl;
            shapes[i]->showdim();
            cout<<"Area is: "<<shapes[i]->area()<<endl;

            cout<<endl;
        }
        
        return 0;
    }