1. C
Programming
Hardik H. Maheta

2. Programming in ANSI C by E Balagurusamy Reference Books
Text Book
Programming in ANSI C by
E Balagurusamy
Reference Books
The C Programming Language by Kerninghan & Ritchie
Let us C by Yashwant Kanitkar
Hardik H. Maheta

3. Program Programming Language What do you mean by Language?
A Set of instructions which when carried out by processor for some specific input, generates specific output.
Programming Language
A specific manner of writing a program with some predefined rules, symbols & their use as a part of language.
i.e. Pascal, C, C++, VC++, JAVA, VB.
Hardik H. Maheta

4. Standardization Committee
History of C
1960
ALGOL
International Group
1967
BCPL
Martin Richards
1970 B
Ken Thompson
1972
Traditional C
Dennis Ritchie
1978
K&R C
Kernighan & Ritchie
1989
ANSI C
ANSI Committee
1990
ANSI/ISO C
ISO Committee
1999
C99
Standardization Committee
Hardik H. Maheta

5. Features of C Structured High-Level Machine-Independent & Portable
Powerful
Efficient
Compact
Close to both man & machine
Fast
Hardik H. Maheta

6. Types of Languages Lower-Level Languages (Machine Language)
-Languages near to the machines
-binary language like
Assembly Languages
Higher-Level Languages
-Languages near to programmers
-C,C++,JAVA
Hardik H. Maheta

7. Hardik H. Maheta

8. Basic Structure of C Programs
Documentation Section (Comment Lines)
Link Section (Link Functions from the System Library)
Definition Section (Defines all Symbolic Constants)
Global Declaration Section (Defining Variables used Globally + Declaration of User Defined Functions)
main ( ) Function Section {
Declaration Part
Executable Part }
Subprogram Section
Function 1
Function 2 and so on …
Hardik H. Maheta

9. Documentation Section
It is set of comment lines
(Name of program, Author details, Aim of program)
What is Comment line??
To guide a programmer. To write a note for
function, operation, logic in between a program.
It is not necessary but used to Increase the readability of program.
Non-executable statement.
i.e /* This is Comment*/
Hardik H. Maheta

10. Link Section It provides instructions to the compiler to link
function from the system library.
# include Directive
To access the functions which are stored in the
library, it is necessary to tell the compiler ,
about the file to be accessed.
Syntax:-
#include<stdio.h>
stdio.h is header file.
Hardik H. Maheta

11. Definition Section It defines all symbolic constants.
#define instruction defines value to a symbolic constant.
#define
It is a preprocessor compiler directive, not a statement.
Therefore it should not end with a semicolon.
Generally written in uppercase.
Syntax
#define PI
Hardik H. Maheta

12. Global Declaration Section
Some variables that are used in more than on function, such variables (global variables) declared in the global declaration section.
It also declares all the user-defined function.
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13. main() function section
Every ‘C’ program must have one main() function section.
It contains two parts
Declaration part
It declares all variables used in the executable part.
Executable part:
It has at least one statement.
All the statement in declaration part and Executable part ends with semicolon(;).
main() function is called by operating system and it returns information to operating system
Hardik H. Maheta

14. Different forms of main() function
Function has no arguments and return no information to operating system.
int main()
Function has no arguments and return integer information to operating system. In this last statement should be return 0;
void main()
Function has no arguments and Explicitly define return no information to operating system.
main(void)
Explicitly define Function has no arguments and return no information to operating system.
void main(void)
Explicitly define Function has no arguments and Explicitly define return no information to operating system.
int main(void)
Explicitly define Function has no arguments and return integer information to operating system. In this last statement should be return 0;
Hardik H. Maheta

15. Sample C program
/* Sample Program to print Hello World */ /* Documentation section */
#include<stdio.h> /* link section*/
void main() /* execution of program*/ {
printf(“Hello World”); /*executable statement*/ }
Hardik H. Maheta

16. Sample C program
/* Sample Program to Add two numbers */ /* Documentation section */
#include<stdio.h> /* link section*/
void main() /* execution of program*/ {
int no1=10, no2=5, sum; /*Declaration Part*/
sum = no1+no2;
Printf(“Sum = %d”, sum); /*Executable Part*/ }
Hardik H. Maheta

17. Executing a ‘C’ Program
Creating the Program
Compiling the Program
Linking the Program with functions that are needed from the C Library
Executing the Program
Hardik H. Maheta

18. Compiler Why compiler is require ?
As machine (a processor) can operate only on binary code instruction
If we use higher level language then for execution of the program we must convert it to lower level / machine level
Code.
This task of converting human readable language to machine readable language is done by the compiler.
A program that translates source code into object code is called compiler.
Hardik H. Maheta

19. Interpreter C Compiler
It analyses and executes each line of the source code, without looking at the entire program, unlike the compiler.
Advantage:
It can execute program immediately
Good for small programs
C Compiler
- checks for syntax errors if no error than coverts ‘C source code into object code form which is nearer to machine level language.
Hardik H. Maheta

20. Linker A linker combines object to form an executable program.
As many programming languages allow us to write different pieces of code, called modules which simplifies the task as a large program can be broken down into small, more manageable pieces.
It is Linker which puts all these modules together.
Hardik H. Maheta

21. Hardik H. Maheta

22. Compiling & Executing C Program
If you are using Linux, you could simply use the command gcc –o objfilename cfilename to compile your c program. And ./objfilename to run your compiled C program.
If you are using Turbo C Compiler, you could directly select the compile(Alt+f9) to compile program and run(ctrl+f9) option from the menu-bar.
Hardik H. Maheta

23. Compile Source program Link with System Library
System Ready
Program Code
Enter Program
Edit Source Program
C Compiler
Compile Source program
Yes
Syntax Error No
System Library
Link with System Library
Logic Error
Input Data
Execute Object Code
Logic & Data Error
Data Error
No Error
Output
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24. Block Diagram Represents only -> what should be the input?
-> what will be the output?
One need not to worry about how the result generated
or what will be the logic for the program?
Block Diagram for making addition of two numbers
Input
Output
PROGRAM
No1. & No2.
No1 + No2

25. Algorithm
Specifies steps of doing the things Irrespective of any programming language
Example: Addition of two numbers
Step 1: [Read two numbers]
Read(no1)
Read(no2)
Step 2:[add two numbers into sum]
summation = no1 + no2
Step 3:[Display the result]
write (summation)
Hardik H. Maheta

26. Flowchart Represents the flow of program Symbols Start-Begin/End
Input/output Rectangle
Process box/operation box
Decision Box
Connector
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27. Write Summation on monitor
Flowchart-example
Example: To add two numbers and display the result.
Start
Read No1 and No2 from user
SUMMATION = NO1 + NO2
Write Summation on monitor
End
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28. Thank You
Hardik H. Maheta