The document provides an introduction to C++ programming, detailing its development in the 1980s by Bjarne Stroustrup at Bell Labs as an extension of the C language. It outlines key concepts in object-oriented programming, such as classes, objects, constructors, and destructors, while noting that C++ is not fully object-oriented. Additionally, it includes code examples demonstrating class and object creation, alongside explanations of member functions and data handling.

1. Introduction to C++
BY SANHITA GHOSAL (MUKHOPADHYAY)
LECTURER, SAROJINI NAIDU COLLEGE FOR WOMEN

2. Birth of C++
 Developed in early 80s at Bell Lab.
 Developed by Bjarne Stroustrup.
 It was based on C.
 The OOP features were added later by Stroustrup.
 It’s a superset of C, ie, any valid C program is also a valid program in
C++ too.

3. Features of Object Oriented
Programming
 Abstraction
 Encapsulation
 Inheritance
 Polymorphism

4. “
”
C++ is not fully Object
Oriented Language. It’s a
Object based Language.
a) Main function is outside the class
b) Use of Friend function

5. Class
 Classes are like a blue print or a template or a plan of
what data is to be stored and what functionalities can be
added with those data.
Book
Data :
ISDN CODE
Book Name
Author Name
Publisher’s Name
Price
Functionalities:
Adding new books
Modifying Price

6. Objects
 The single unit that combine the data and the functions that
operate on that data is called an object.
 Objects are examples of a Class.
 They can represent the real world entities.
 Objects are the only way to access the data.
 E.g. “Gulliver’s Travel” is an example of class Book.

7. Starting with C++
 Save the file as filename.cpp (.cpp is the extension of the c++ file).
 Compile to get the object file as filename.obj
 Link and make executable to get executable file as filename.exe
compile compile
Linking
File1.cpp File2.cpp
File1.obj File2.obj
File.exe

8. Introduction to classes and its
features
#include<iostream>
Using namespace std;
Class Example {
private:
int data1;
float data2;
public:
Example() {
data1=0;
data2=0.0;
}
Example(int d1,float d2){
data1=d1;
data2=d2;
}
void getData(int d1,float d2){
data1=d1;
data2=d2;
}
void putData() {
cout<<data1;
cout<<data2;
}
~Example()
{
}
};

9. Members of a class
Member Data
 data1
 data2
Member Methods
 Example()
 Example(int,int)
 getData(int, int)
 putData()

10. Constructors
 Is a special member function which is called automatically
whenever an object is create.
 It defines an object, reserves space in memory for the object.
 The name of the constructor must be same as the name of the class
to which it belongs.
 Constructor are of two types mainly – Default and Parameterized.
 Default constructor takes no parameter but parameterized
constructor can take any no of parameters.
 Constructor never returns any value.

11. Other member methods
 Void getData(int d1,int d2)
 Void putData()

12. Destructor
 Destructor is a special member method which is called
automatically when an object is being destroyed.
 Destructor generally deallocates the memory allocated to an
object.
 Destructor also has the same name as the class.
 Destructor takes no parameter and returns no value.

13. The entry point of a program…
 Void main()
 {
 Example ex1,ex2;
 Example ex3(5,5.2);
 int a;
 float b;
 cout << “Enter an number element : :”;
 cin >> a;
 cout << “Enter an fractional element”;
 cin >> b;
 ex2.getData(a,b);
 ex1.putData();
 ex2.putData();
 ex3.putData();
 }

14. Creation of objects
 Example ex1 - > default constructor is called
 Example ex3(5,5.5) -> parameterized constructor is called
 ex2.getData(a,b) -> member method is called to set the input to
the member data
 ex1.putData() ->member method is called to display the data
members.

15.  cout is used to print
 Cin is used to get input from the user.
 They both are objects of iostream class