program to demonstrate the use of constant member functions? (C plusplus or C++)

Aim: Write a program to demonstrate the use of constant member functions?

Ans:

#include<conio.h>

#include<iostream.h>

class  constant

{

int a,b,c;

public:

       void input()

            {

                        a=10;

                        b=20;

                        c=30;

            }

             void const  output()

            {

                        cout<<"a="<<a<<"b="<<b<<"c="<<c;

                        //This member function cannot  modify the numbers

            }

}x;

void main()

{

            clrscr();

            x.input();

            x.output();

            getch();

}