Explain virtual functions, C/C++ Programming

Assignment Help:

Virtual Functions

The keyword virtual was previously used to resolve ambiguity for a class derived from two classes, both having a common ancestor. These classes are known as virtual base classes. This time it helps in implementing the idea of polymorphism with class inheritance. The function of the base class can be declared with the keyword virtual. The program with this change and its output is given below.

                class Shape

                 {

                  public :

virtual void print()

 {

                cout << " I am a Shape " << endl;

 }

                 };

                class Triangle : public Shape

                 {

                  public :

void print()

 {

                cout << " I am a Triangle " << endl;

 }

                 };

                class  Circle : public Shape

                 {

                  public :

void print()

 {

                cout << " I am a  Circle " << endl;

 }

                 };

 

void main()

 {

  Shape S;

  Triangle T;

  Circle C;

                S.print();

                T.print();

                C.print();

 

                  Shape *ptr;

 

                                ptr = &S;

                                ptr -> print();

 

                                ptr = &T;

                                ptr -> print();

 

ptr = &C;

                                ptr -> print();

}

 


Related Discussions:- Explain virtual functions

Padovan string., #question.A Padovan string P(n) for a natural number n is ...

#question.A Padovan string P(n) for a natural number n is defined as: P(0) = ‘X’ P(1) = ‘Y’ P(2) = ‘Z’ P(n) = P(n-2) + P(n-3), n>2 where + denotes string concatenation. For a s

Area under curve, Write a program to find the area under the curve y = f(x)...

Write a program to find the area under the curve y = f(x) between x = a and x = b, integrate y = f(x) between the limits of a and b. The area under a curve between two points can b

Program, Define a class polynomial with three private data members a, b and...

Define a class polynomial with three private data members a, b and c of type double to represent the coefficient of two degree polynomial(ax^2+bx+c). Include a constructor in a pol

C program for merge two strings , v\:* {behavior:url(#default#VML);} o\:* ...

v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} Normal 0

When i throw this object, A: Depends. Might be "zero" Objects which are ...

A: Depends. Might be "zero" Objects which are thrown must have a publicly accessible copy-constructor. The compiler is permitted to generate code which copies the thrown object

Explain input output function, Input Output Most languages have "statem...

Input Output Most languages have "statements" to perform I/O . Though in C and C++ we use "functions" to perform I/O. C++ also has its own I/O mechanism - the cin and cout obje

Library functions, is getchar() is a C++ library function?

is getchar() is a C++ library function?

Loops, how to make a diamond from steric

how to make a diamond from steric

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd