Principles Of ProgrammingusingC
Subject Code : 22POP13 CIEMarks: 50
SEEMarks: 50
Lecture Hours : 40
Credits : 03
Arun Kumar P
Dept. of ISE, JNNCE, Shivamogga
06HoursIntroductionto
C
Arun Kumar P
Dept. of ISE, JNNCE, Shivamogga
Introduction
to
computers
• History: In
1822, Charles
Babbage
begandevelopingwhatfirst mechanical computer.
• And then in 1833 he actually designed an Analytical Enginewhich
was a general-purpose computer. • It contained an ALU, some basic
flowchart principlesandtheconcept of integrated memory.
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction
to
computers
• 1st Generation
(1940 to 1955): Vacuumtubes usedforthecircuitry .
Example: ENIAC, UNIVAC-1, EDVAC. • 2nd Generation
(1957-1963): Advanced vacuumtubesortransistors used for the
circuitry . Example: IBM 1620, IBM7094, CDC1604, CDC3600
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction
to
computers
• 3rd Generation
(1964-1971): Integrated circuitsusedforthecircuitry .
Example: IBM-360 series, Honeywell-6000series, and the
IBM-370/168.
• 4th Generation (1971-1980): Microprocessors usedExample:
STAR 1000, PDP 11, CRAY-1, CRAY-X-MP,andApple II
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction
to
computers
• 5th Generation (1980 onwards): Ultra LargeScaleIntegrated
circuits used for the circuitry . Example: IBM, Pentium, Desktop,
Laptop, Notebook, Ultrabook, and so on.
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction
to
computers
• A computer as an electronic device • Accept data as
input
• Perform the required mathematical and logical operations•
Output the result
Arun Kumar P
Dept. of ISE, JNNCE, Shivamogga
Introduction
to computers
• A computer is a combination of hardware andsoftware•
Hardware are the physical components of a
computerlikeprocessor, memory, devices, monitor, keyboardetc. •
Software is the set of programs or instructions that arerequired by
the hardware to performvarious operationsasperthe requirement of
users
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction
to
computers
Basic Computer
Organization
• Computer basically
performs five major
operations1. Accepting data or
instructions (input)
2. Storing data
3. Processing data
4. Displaying results (output)
5. Controlling and coordinating all
operations inside a computer
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction
to
computers
Components of
Computer
1. Memory
2. Disks
3. Processor
4. Peripheral
Devices/Input and
Output Devices
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction
to
computers
Components of
Computer:
Memory • Memory
is an internal storage , used to store dataandprograms either
temporarily or permanently• Dived as Primary memory and
Secondary memory• Primary memory (Main Memory) holds
instructionsanddata when a program is executing • Volatile in
nature, high speed and Costly (RAMandROM)
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction
to
computers
Components of Computer: Disks • Secondary memory
(Auxiliary) holds data andprogramsthat are not currently in use and
provides long-termstorage• Non-volatile, low speed and cheaper
(HardDisks)
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction
to computers
Components of Computer: Disks
Arun
Kumar P
Dept. of ISE, JNNCE, Shivamogga
Introduction
to
computers
Components of
Computer:
Processor
• Processor consists
two main parts
ALU&control
unit(CU)• Also
Registers,
Execution unit &bus interfaceunit (BIU)
Arun Kumar P
Dept. of ISE, JNNCE, Shivamogga
Introduction
to computers
Components of Computer: Processor
Arun Kumar P
Dept. of ISE, JNNCE, Shivamogga
Introduction
to
computers
Components of
Computer:
Pheripheral /
IODevices
• To interact with
computer
pheripheral devices
required• Input
Devices are used to
feed data and instructionsintothecomputer
Arun Kumar P
Dept. of ISE, JNNCE, Shivamogga
Introduction
to
computers
Components of
Computer:
Input Devices
Arun
Kumar P
Dept. of ISE, JNNCE, Shivamogga
Introduction
to computers
Components of Computer: Input Devices
Arun Kumar P
Dept. of ISE, JNNCE, Shivamogga
Introduction
to
computers
Components
of Computer:
Output Devices
Arun Kumar P
Dept. of ISE, JNNCE, Shivamogga
Introduction
to computers
Components of Computer: Output Devices
Arun Kumar P
Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing Efficient
Programs:
ProgrammingParadigms•
Paradigm is a fundamental
style of programmingthat defineshow the sructure and basic elements
of a Computerprogramwill be built.
• The style of writing programs and the set of
capabilitiesandlimitations that a particular programming
languagehasdepends on the paradigm it supports.
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing
Efficient
Programs: ProgrammingParadigmsClassifications
1. Monolithic programming - Emphasize on findingasolution2.
Procedural programming - Lays stress on algorithms3. Structured
programming - Focuses on modules
4. Object-oriented programming - Emphasiszes
onClassesandObjects
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing
Efficient Programs:
ProgrammingParadigmsClassifications
5. Logic-oriented programming - Focuses on goals, usualyexpressed
inpredicatecalculas
6. Rule-oriented programming - Makes use of
if-then-elserulesfor computation
7. Constraint oriented programming- Utilizes invariant
relationships tosolveproblem
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing Efficient Programs:
ProgrammingParadigmsClassifications : Monolithic
Programming
ADB 10
Global Data
BDB 20
SUM DB?
MOV AX, A
ADD AX, B
Sequential Code
MOV SUM, AX
JMP STOP
….…………
STOP: EXIT
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing Efficient
Programs:
ProgrammingParadigmsClassifications : Monolithic
Programming • Only one programming module • Cosnsists Global
data and sequential code • Global data can be accessed and
modified byanypartoftheprogram
• All instructions are executed in specified sequence
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing Efficient
Programs:
ProgrammingParadigmsClassifications : Monolithic
Programming • Example: Assembly Language and
BASICLimitations: - Serious threat to its Data Integrity- Do not
support concept of subroutine
- Program size is very big and difficult todebug
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing Efficient
Programs: ProgrammingParadigmsClassifications : Procedural
Programming
Global Data
Subroutine
Program
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing Efficient Programs:
ProgrammingParadigmsClassifications : Procedural
Programming • Program divided into subroutines that access
global data• Example: FORTRAN and COBOL Advantages:
1. Easy to write compare to monolithic program
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing Efficient
Programs: ProgrammingParadigmsClassifications : Procedural
Programming Dis-advantages:
1. No concept of reusability 2. Requires more time and effort
to write programs3. Programs are difficult to maintain 4. No
data integrity
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing Efficient
Programs:
ProgrammingParadigmsClassifications : Structured
Programming Global Data
Program
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing Efficient
Programs: ProgrammingParadigmsClassifications : Structured
Programming - Modular programming, programbroken
intomodules- Suggested by Corrado Bohm and Guiseppe Jacopini
in1966- To down approach
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing Efficient
Programs: ProgrammingParadigmsClassifications : Structured
Programming Advantages
- Easy to understand
- Code can be reused
- Less time to code
- Easy to debug
- Easy to change
- Emphasis on code instead on data
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing Efficient
Programs: ProgrammingParadigmsClassifications : Structured
Programming Dis-Advantages
- Not data-centered
- Global data may inadvertently modified - Main focus is on
functions
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing
Efficient Programs:
ProgrammingParadigmsClassifications : Object
Oriented Programming
Object 1
Object 1
Object 3
Object 4
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing
Efficient
Programs:
ProgrammingParadigmsClassifications : Object
Oriented Programming- Treats data is the critical element
- Restricts free movement of data in system- Task-based
and data-based
- Task and data grouped together in entity knownobject
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing Efficient
Programs: ProgrammingParadigmsClassifications : Object
Oriented Programming: Features- Programs are data centered Programs are dived in terms of Objects - Functions that operate on
data - Data is hidden
- New data and functions can be added as and whenrequired- Bottom
up approach
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Designing Efficient
Programs : SDLC
AnalysisDesign Implementation
Requirement
S/W Deployment,
Testing
Training and
support Maintenance
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Program Design Tools: Algorithms - Step by step
procedure to solve the problem- Provides blue print to
write program
- Effective procedure for solving the
probleminafinitesteps-> Must be presise
-> Be unambiguous
-> Must not be infinite statements -> Results must
be obtained
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Program Design Tools: Flowcharts - Graphical / pictorial
representation of problemsolvingstepsNotations
(Oval / Rounded Rectangle) Start / Stop
(Parallelogram) Input / Output
(Rectangle) Processing / Computation steps
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Program Design
Tools: Flowcharts - Graphical / pictorial representation of
problemsolvingstepsNotations
(Diamond Shape) Decision statements
(Small circle) Connector
(Arrows) Control Flow direction
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Program
Design Tools: Flowcharts Advantages
- Used for program documentation - Helpful to solve
complex problems - Error free programs can be
implement - Can be used to debug the program
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Program
Design
Tools: Flowcharts Dis-advantages
- Time consuming and need more human resource- Flowchart of
complex program become clumsy- Little modification in coding
requires to redrawentireflowchart
- No well-defined standards
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Program Design
Tools: Pseudocodes -
Compact and informal high-level descriptionof analgorithmUses structural conventions of programminglanguage- Focuses
on logic of the program
- Syntax neutral
- Enhance human understandability of the solution
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Program
Design Tools: Pseudocodes Example:
1. Read the radius of circle
2. Calculate are of the circle
3. Print the area of the circle
4. End
Variables: redius of the circle, area
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Types of Errors
Types of Errors
Run-time Errors Compile-time Errors Linker Errors Logical Errors
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Types of Errors :
Run-time Errors - Occurs during the execution of the
programOccurs when some illegal operations like 1. Dividing
a number by zero 2. Opening a file that already exists 3. Lack
of free memory space
4. Finding square or logarithm of negative numbersRun-time
errors may terminate programexecution
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Types of Errors :
Compile-time Errors -
Occurs during the compilation, classified as 1. Syntax Errors:
When rules of the programminglanguageviolated
2. Semantic Errors: May comply with rules of
programminglanguage but are not
meaningful tothe
compiler
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Types of Errors :
Compile-time Errors - Occurs during the compilation, classified as
3. Logical Errors: Results unexpected and undesirableoutputWill
not be detected by compiler
May occur due to incorrect statements
4.Linker Errors: Occurs when linker is not
abletofindthefunction definition for a
givenprototype
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Testing and Debugging : Testing - An activity to verify correct
behaviour of the programImplementation Stage
1. Unit Test: Testing single unit / module 2.Integration Test:
Combined units and interfaces aretested3.System Test: Checks the
entire system
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Testing and Debugging
: Debugging - An activity that includes execution testing
andcodecorrection- Main aim is locate the errors and fix
themDiffrent Approaches are
1. Brute-Force Method: CPU registers and
Memorylocations2.Backtracking Method: Locate first and
tracingbackword3.Cause Elimination: List of all possible causes
of anerrorisdeveloped
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C :
Introduction - Developed early by 1970 by Dennis Ritchie at
Bell Laboratory- Used by UNIX OS
- Named ‘C’ because many featuers are derivedfromB
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C :
Taxonomy ALGOL BPCL B Traditonal C K & R C ANSI C
C99 C95 ANSI / ISO
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C :
Background - Derived from ALGOL (first lanuage with
blockstructure)- In 1967 Martin Richards developed
BPCL(Typeless)- In 1970 Ken Thompson developed B- In 1972 ,
Dennis Ritchi developed C, supports datatypes- C was documented
and popularized in book ‘TheCProgramming Language by Brian W.
KernighanandDennisRitchie in 1978
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C :
Background - In 1983,
ANSI started working on standard for Candapprovedin 1989 known
as ANSI C - In 1990, ISO adopted ANSI standard, became C89- In
1995 minor changes made on C89, so versionisC95- Later
significant changes made on C95 and modifiedversionC99 came
exist on 1999
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C :
C99 Features -
Extension to character types to support non-EnglishcharactersBoolean Data Types
- Extension to Integer type
- Inclusion of type definitions in for statement - Inclusion of
imaginary and complex types - Addition of // comment
statements
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction
to C : Characteristics of C- Structured programming
- Rich set of built in functions
- 32 Keywords
- Efficient
- Low level programming
- Supports pointers
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C :
Uses of C - Used for dystem programming - Used to develop
compilers, libraries and interpretersforotherlanguage
-Used as an intermediate language for
implementationofotherlanguage
- End user applications
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to
C : Structure of
a CProgramDocument Section
Link Section
#include<stdio.h>
Global Decleration
int main() {
int main() {
Local Decleration
Statement/s }
printf(“Hello C”); }
User defined functions
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C : Files used in CFiles in a C Program
Source File Header File Object File Executable File
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C
: Files used in C- Header files
Ex: stdio.h stdlib.h string.h math.h- Source code files
Ex: circle.c sample.c
- Object files
Ex: circle.o sample.o
- Binary executable file
Ex: circle.exe sample.exe
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C :
Compiling and ExecutingCProgramSource File Compiler Object Files
Linker
Executable
Files
Library Files
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C : Comments - Single line
comment statement
//This is single line comment statement
- Multi line comment statement
/* This is multi line comment statement can use for
multi lines
*/
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C : C Tokens - Tokens are basic building blocks in
Clanguage- Smallest individual unit in C - Program is constructed
using a combination of tokens- There are six types of tokens
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction
to C : C
Tokens Tokens in C
Keywords
Variables
Constants
Strings
Special Characters
Operators
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C :
Identifiers - An identifier is “name given to programelements”Which help us to identify elements of the program- Such as
Variables, Keywords, Funtions etc Example: radius area p length
int float void
main printf scanf
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C :
Identifiers Rules for
forming identifier names 1. Names may formed with
combinations of letters, digitsandunderscore
Example: total sum2 sum_of
2. Names must begin with letter or underscore Valid: marks rollno
_total
Invalid: 2marks #rollno @usn
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C :
Identifiers Rules for
forming identifier names 3. Keywords cannot be used as identifier
name Invalid: int float
4. Identifier names are ase sensitive sum Sum SUM all are
different
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C : Identifiers Rules for forming
identifier names 5. First 31 characters are significant
summation_of_two_numbers
salary_of_employee_for_december_month
6. Two successive underscores are not allowedInvalid:
balance__of
Valid: balance_of
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C : Keywords in C- Keywords are predefined
words - Keywords meaning are fixed - Keywords are reserved,
cannot be used as identifiers- Keywords must be written in
lower case / small letter
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C :
Keywords in Cauto break case char const continuedefault do
double else enumexternfloat for goto if int longregister return
short signed sizeof staticstruct switch typedef union
unsignedvoidvolatile while
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C :
Character set in C- Any
letter from English
Alphabet, digit or special
symbol- Combined to form C token 1. English Alphabet: a - z and
A - Z 2. Digits: 0 - 9
3. Special Characters: ~ # %^ &*{}<> = _ + - $/ ()
\ ; : [ ] ‘ “?.
!|,@
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C : Character set in C4. White space
characters:
White Space Characters\b
Mea
Blank Spac
\t
Horizontal T
\v
Vertical retu
\r
\f
\n
New Line
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C : Character set in C5. Escape sequence
P
Escape sequence\a
Audible sign
\b
Backspace
\t
Tab
\n
New Line
\v
Vertical Tab
\f
N
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C : Basic
Data Types in C
Data
Type Keywo
Use
Character char
Integer
int
Floating
Point
float
Double
double
Valuless
void
1
in bytes Value
-128 to 127
2
Use
To storechara
-32
32767 To storein
numbers
3.4
3.4E+38 To storeflo
point numbers
8
1.7E
1.7E+308 To sto
floatingpoint
numbers
0
No v
4
-
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C : Basic
Data Types in C
Data Typechar
Size
1
unsigned
-128 to 127
char 1
int
2
unsigned
in bytes Value range
0 to 255
-32768 to 32767
int 2
0 to 65535
short int
2
-32768 to 32767
unsigned
short int 2
0 to 65535
lon
unsigned
-2147483648 to 2147483647
long in
0 to 4294967295
Arun Kumar P
Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C : Basic
Data Types in C
Data Typefloat
Size
4
double
3.4E-38 to 3.4E+38
8
long
in bytes Value range
1.7E-308 to 1.7E+308
10
3.4E-4932 to 1.1E+4932
Arun Kumar P
Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C :
Variables - Name
given to memory
location - Using the
variable, refers to adress of the memorylocationLogical
Physical
Memory
Address
Address
Location
.
.
.
1000
radius
1002
area
.
.
.
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C : Variables Two kinds:
1. Numeric Variables: - Used to store integer or
floatingpointvalues / numbers (321.5)
- For integer variables, default values
are signed
2. Character Variables: - Used to store characters- Values are
placed insingleqoutes
Example : ‘a’ ‘A’ ‘5’ ‘@’
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C : Variables Declaring
Variables:
- Each variable must be declared before used intheprogram-To
declare the variable, appropriate data type must beused- Data types
indicates to compiler, kind of values will bestored in it
- Variable must not be declared with void type
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga
Introduction to C
Introduction to C : Variables Places to Declare
Variables:
- Variables can be declared at 3 places 1. At global scope
(Outside of all functions) 2. At loacl scope (Inside of the
function) 3. At function definition (Formal parameters)
Arun Kumar P Dept. of ISE, JNNCE, Shivamogga