Explain pure virtual functions, C/C++ Programming

Assignment Help:

Pure Virtual Functions

An abstract class is one, which is used just for deriving some other classes. No object of this class is declared and used in the program. Likewise, there are pure virtual functions which themselves won't be used. Consider the above example with some changes.

class Shape

                 {

                  public :

virtual void print() = 0; // Pure virtual

                             function

                 };

                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;

 

                  Shape *ptr;

 

                                ptr = &T;

                                ptr -> print();

 

ptr = &C;

                                ptr -> print();

                }

 


Related Discussions:- Explain pure virtual functions

Develope a program, Develop a program to meet the following requirements: ...

Develop a program to meet the following requirements: 1. Must use at least one function in addition to main (you can use more) 2. Must use selection 3. Must use deference/indire

Do i require checking for null before delete p?, No. it's not required T...

No. it's not required The C++ language guarantees that delete p will do nothing if p is equivalent to NULL. As you might get the test backwards, and as most testing methodologie

How to define a derived class, How to define a derived class ? A singly...

How to define a derived class ? A singly inherited derived class id defined by writing : The keyword class. The name of the derived class . A single colon (:).

Why are all header files not declared in every c program, Why are all heade...

Why are all header files not declared in every C program? - Declaring all header files in each program would result in increase in overall file size and load of the program. It

Program to find a greatest string: c - program , Program to find a Greatest...

Program to find a Greatest String: C - Program: Write a program find largest string by c program. int main( int argc, char *argv[] ) {     if( argc         {

When does a name clash occur in c++, A name clash happens when a name is de...

A name clash happens when a name is described in more than one place. For example, two dissimilar class libraries could give two different classes the similar name. If you try to u

Compiling/ installing openvpn client within an ip camera, Project Descripti...

Project Description: I want someone with experience on adding/compiling/installing the OpenVPN client software within an IP network camera's embedded operating system. Either if

PEBBLE MERCHANT, C CODE FOR PEBBLE MERCHANTS PROBLEM

C CODE FOR PEBBLE MERCHANTS PROBLEM

Program to spider''s path display to the screen, Spider webs have two types...

Spider webs have two types of silk, sticky silk and strength silk, spiders do not move on the sticky silken threads only on the strength threads. Assume one type of spider creates

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