CPP

Lecture 1 : INTRODUCTION TO C++

History of C++

• C++ was developed by Bjarne Stroustrup in 1979 at AT & T’s Lab, it was called C with Classes
• C++’s OOP aspect was inspired by a computer simulation language called simula67
• JAVA is written in C++
• Major OS of modern times are written in C++

Features of C++

• C++ is a middle level language
• C++ supports principles of OOP
• C++ joins three separate programming traditions
  • The procedural language tradition, represented by C
  • The Object-Oriented language tradition, represented by Class enhancement C++ adds to C
  • generic programming, supported by C++ templates

Comparision between C and C++

• C++ is a super set of C language
• C++ programs can use existing C software libraries
• C follows top down approach of programming
• C++ follows bottom up approach of programming
• C adopts Procedure Oriented Programming (POP)
• C++ adopts Object Oriented Programming (OOP) as well as POP

Object Oriented Programming

• OOPs is a programming approach which revolves around the concept of “Object”
• Any entity in the system that can be defined as a set of properties and set of operations performed using entity’s property set, is known as object.
  • Encapsulation
  • Data Hiding
  • Abstraction
  • Polymorphism
  • Inheritance

Concept of Classes and Objects

• Class is a blueprint of an Object
• Class is a description of Object’s Property set and set of operations
• Creating class is as good as defining a new data type
• Class is a means to achieve encapsulation
• Object is a run time entity
• Object is an instance of a class.

Example :

class box
{
    int l,b,h;
    void setDimension(int x, int y, int z)
    { 
	//something
    }
    void showDimesion()
    {
        //something
    }
};

//now we can create an object like this
box b1;

Software Development in C++

• software dev process in c++ is very similar to that of c language
• first we make a file and write our code in it
• save this file with extension cpp
• this file contains many preprocessor statements like #include
• our file (say sum.cpp) will go to preprocessor where preprocessor will see all preprocessor statements and write code in their place using header files
• a sum.i file will be made in RAM
• this sum.i file will go to compiler now where it will get converted into machine readable form (binary) and sum.obj will be formed
• but there must still be some unknown code which will be solved by linker by linking library files
• now we will get a sum.exe file which can be used to run the program