now lets begin our second session...

header files-

Include statements call include files (sometimes also referred to as "header files") which are text files containing

information about function declarations, constants and structures. When your program is compiled, the

information in the specified include file is 'pasted' directly into your program.

/* Examples: */

#include	math.h	incl. file with math. function info
#include	stdio.h	include file with I/O info
#include	time.h	include file with time funct. info
#include	graph.h	include file with graphics info
#include	myconst.h	see example directly below

Function Declarations -

There are two different categories of functions that you will use in your C programs: predefined

functions and functions that you will write.

Predefined functions were written by someone else and are stored in some function library on your

hard disk, ready to be used by anyone who so desires. During the course we will provide you with

predefined functions to simplify the programming needed in the lab.

These functions consist of a core of standard ANSI C functions that cover most basic programming tasks

such as input and output, file maintenance and the basic mathematical functions.

Do not panic when you look over the list of functions; of the hundred or

so functions, you really need to know only about 10 functions but you should be aware that some of the

other ones exist. Here is a table of functions that you should know:

Function Include

Name	File Description	Usage
printf( )	stdio.h	Prints formatted data to screen Display numbers and text
scanf( )	stdio.h	Reads in formatted data. To read in numbers
puts( )	stdio.h	Prints character string to screen Display text
gets( )	stdio.h	Reads in a string (termin. by carriage return) To read in text
kbhit( )	conio.h	Detects if any key on keyboard has been hit To stop a repeated process
inp( )	conio.h	Reads a byte of data from a port Computer interfacing
outp( )	conio.h	Sends a byte of data to a port Computer interfacing
malloc( )	stdlib.h	Creates a data buffer Arrays and data input
rand( )	stdlib.h	Creates a random # between 0 and 32768 Simulations, Tests
pow( )	math.h	Calculates x
sqrt( )	math.h	Calculates x

Global Variables -

Any variables declared outside of 'main' will be global, i.e. they can be "seen" by 'main' and any other

functions.

If you don't understand what local and global variables are, don't worry; they are explained in more.

main( ) -

Every C program needs a 'main' function. This is the place where the main body of your code is

placed. A successful C program executes all the statements placed in main. Functions are only executed

if they are called from within 'main'. Main is the only C function that doesn't need to be declared.

Now lets start some programing -

#include

#include

void main( )

{

printf("is innovation is better then dreaming");

}

getch();

}

if you are using turbo c++ compiler then

for compiling use alt+F9

for running the program use ctrl+F9

let see whats the output-

is innovation is better then dreaming

thats all folks..please make it revise it all the things that i delivered today..from tommorow onward we will go for real programing.