WRITING A OWN CLASS

 #include<iostream>

using namespace std;

class rectangle

{

    public:

    int length;

    int breadth;

    int area()

    {

        return length*breadth;

    }

    int perimeter()

    {

        return 2*(length+breadth);

    }

    int sum()

    {

        return length+breadth;

    }

    int rec()

    {

        return 4*(length+breadth);

    }

};

int main()

{

    rectangle r1,r2;

    r1.length=10;

    r1.breadth=20;

    cout<<"The area r1 is :"<<r1.area()<<endl;

    cout<<"The perimeter of r1 is :"<<r1.perimeter()<<endl;

    cout<<"The sum r1 is : "<<r1.sum()<<endl;

    cout<<"The rec r1 is : "<<r1.rec()<<endl;

    r2.length=20;

    r2.breadth=30;

    cout<<"The area of r2 is :"<<r2.area()<<endl;

    cout<<"The perimeter of r2 is :"<<r2.perimeter()<<endl;

    cout<<"The sum r2 is : "<<r2.sum()<<endl;

    cout<<"The rec r2 is : "<<r2.rec()<<endl;

}