This document provides an overview of basic C++ programming concepts including: 1) Preprocessor directives like #include are used to include standard header files like iostream. Header files contain pre-defined functions. 2) The main() function is where program execution begins. Statements written within the curly braces of main() comprise the program body. 3) Output is displayed using the cout stream object and insertion operator <<. Common output commands print text to the standard output on the monitor.

1. DUEt
Computer Systems Engineering

2. Basic Program

3. I am use Dev c++

4. Basic Program
1. Preprocessor:
# is used to start a program is called preprocessor directory. Directory is an
instructions given to compiler before completing of actual program
preprocessor directory are handled by a program.
2. Include preprocessor:
It is used to include standard header files in the program. It is also a
preprocessor directive.
# include <iostream>
In which iostream is a header file.
Iostream= input-output stream.

5. 3. Header files:
It is a collection of standard library functions perform different tasks. Header files also
known as include files, source files, copy books. This files contain different types of pre-
defined functions.
e.g. iostream, stdio, conio, list, set, limits, etc.
There are 49 header files in the standard c++ library.
4. Main Function:
When the program runs, the control entire main( ) function and starts
executing its statement. All c++ program are divided into units called
functions. Any number of statements can be written in the body of the main
function.
Main function( )
{
body of the statements;
}

6. 5. Statements:
The program is written in curly braces called delimiters. The statement is collecting
known as body of the program.
{ called open delimiter.
} called closed delimiter.
E.g.
{
cout<<“Hello World”<<endl;
return 0;
}
6. Output Command:
The term standard output refers to the output display on monitor. C++ uses the cout
stream object to display standard output. The things written in the quotation marks is
called character string.
E.g.
cout<<“Hello World”<<endl;

7.  The operator << is called insertion.
 The operator >> is called stream extraction.
 Endl or semicolon (;) are called terminator. It is used go to next / new line.
Termination sign shows that the instruction is completed.
 In turbo c programming app in which we use Clrscr ( ); it is used to clear
the output screen.
 Return is not a necessary thing in main function. Its only used if you start
your body with int main(). Then you have to write return 0; at the end. If
you use void main(), then you do not have to call return.