POLYMORPHISM

AIM:
         To implement a C++ program to add and subtract two numbers using polymorphism

ALGORITHM:

Step 1: Include the header files

Step 2: Declare the base class base

Step 3: Declare and define the function setVar() and getresult()

Step 4: Create a pure virtual function op ()

Step 5: Create two derived classes add and sub from base class

Step 6: Declare the virtual function op ()

Step 7: Create an object pointer for base class

Step 8: Create an object for derived classes and access the member functions to find the result.

PROGRAM:

#include <iostream.h>

 using namespace std;

 // abstract base class

class base

{

    protected:  // attribute section

int num1;

        int num2;

        int result;

    public:  // behavior section

    void setVar(int n1,int n2)

        {

            num1 = n1;

            num2 = n2;

        }

        virtual void op() = 0;  // pure virtual function

        int getresult() {return result;}

};

class add: public base  // add class inherits from base class

{

  public:

      void op() {result = num1 + num2;}

};

 //sub class inherit base class

class sub: public base

{

  public:

      void op() {result = num1 - num2;}

};

 int main()

{

    int x,y;

    base *m; //pointer variable declaration of type base class

    add ad;  //create object1 for addition process

    sub su;  //create object2 for subtraction process

    cout << "\nEnter two numbers separated by space, or press Ctrl+z to Exit: ";

     while(cin >> x >> y)

    {

        m = &ad;

        m->setVar( x , y );

        m->op(); //addition process, even though call is on pointer to base!

        cout << "\nResult of summation = " << m->getresult();

        m = &su;

        m->setVar( x , y );

        m->op(); //subtraction process, even though call is on pointer to base!

        cout << "\nResult of subtraction = " << m->getresult() << endl << endl;

        cout << "\nEnter two numbers seperated by space or press Ctrl+z to Exit: ";

    }

    return 0;

}

SAMPLE OUTPUT:

Enter two numbers separated by space, or press Ctrl+z to Exit: 88  9

Result of summation = 97

Result of subtraction = 79

Enter two numbers separated by space or press Ctrl+z to Exit: ^Z

Process returned 0 (0x0) execution times: 102.711 s

Press any key to continue.

*/

RESULT:

                Thus a C++ program to add and subtract two numbers using polymorphism is implemented successfully.