CS 192

1
CS 192

• Problem Solving and Computer Programming
• Winter 2003
• Instructor
• Dr. Shafay Shamail
• TA
• Adeel Zafar
• Ibrar Javed

2
Schedule
3
Description

• This first level programming course shall cover
  the principles and practice of problem solving
  using C.
• Students shall be introduced to the basic C
  techniques such as program control statements,
  pointers, functions, structures etc.
• The students shall gain hands-on experience
  through several programming assignments.

4
Text Books

• Primary
• Herbert Schildt, C from the Ground Up, 2nd
  Edition, 1998, Osborne McGraw-Hill.
• References
• Deital Deital, C How to Program, 3rd
  Edition, 2001, Prentice Hall.
• Herbert Schildt, C The Complete Reference,
  3rd Edition, 1998, Osborne McGraw-Hill.
•  
• Some handouts may be given to supplement the text

5

• Lectures
• There shall be 30 sessionso       20 sessions of
  75 minutes eacho       Up to 8 labs of 100
  minutes each conducted by TA
• Grading
• o          15 Quizzes (quizzes may be based on
  assignments)o          10 Programming
  Assignments.o          15 Labso          25
  Midterm Examo          35 Final Exam

6
Topics
7
Topics
8
Topics
9
Scholastic Ethics

• Students are expected to maintain high
  standards of academic honesty. The Disciplinary
  Committee will deal with breaches in scholastic
  ethics such as cheating.
•     Plagiarism will be suspected if an
  assignment that calls for independent development
  and implementation of a program results in two or
  more solutions so similar that one solution can
  be converted to the other(s) by a series of
  simple commands
•     Cheating will be suspected if a student who
  completed an assignment independently cannot
  explain both the intricacies of the solution and
  the techniques used to generate that solution

10
Examples of Cheating

• Turning in someone else's work, in whole or in
  part, as your own (with or without his/her
  knowledge)
• Turning in a completely duplicated assignment is
  a flagrant offense
• Allowing another student to turn in your work as
  his/her own
• Several people writing one assignment and turning
  in multiple copies, all represented (implicitly
  or explicitly) as individual work

11
Examples of Not Cheating

• Turning in work done alone or with the help of
  the course's TAs.
• Submitting one assignment for a group of students
  if group work is explicitly permitted (or
  required)
• Getting or giving help about using the computers
• Getting or giving help about solving minor syntax
  errors Penalties for cheating can be an 'F' in
  the course or worse.

12
What is a Computer?

• Computer
• A device capable of performing computations and
  making logical decisions
• Computer programs
• Sets of instructions that control a computers
  processing of data
• Hardware
• Various devices comprising a computer
• Examples keyboard, screen, mouse, disks, memory,
  CD-ROM, and processing units
• Software
• Programs that run a computer

13
Computer Organization

• Six logical units in every computer
• Input unit
• Obtains information from input devices (keyboard,
  mouse)
• Output unit
• Outputs information (to screen, to printer, to
  control other devices)
• Memory unit
• Rapid access, low capacity, stores input
  information
• Arithmetic and logic unit (ALU)
• Performs arithmetic calculations and logic
  decisions
• Central processing unit (CPU)
• Supervises and coordinates the other sections of
  the computer
• Secondary storage unit
• Cheap, long-term, high-capacity storage, stores
  inactive programs

14
A Bit of History

• Which was the first programmable computer?
• Charles Babbages Analytical Engine (early
  1800s)
• First programmer?
• Ada Augusta, Countess of Lovelace Charless
  colleague and daughter of Lord Byron

15
The Analytical Engine has no pretensions
whatever to originate anything. It can do
whatever we know how to order it to perform. It
can follow analysis but it has no power of
anticipating any analytical relations or truths.
Its province is to assist us in making available
what we are already acquainted with. -Ada
Augusta, Countess of Lovelace
16
Evolution of Operating Systems

• Batch processing
• Do only one job or task at a time
• Operating systems
• Manage transitions between jobs
• Increased throughput
• Amount of work computers process
• Multiprogramming
• Many jobs or tasks sharing a computers resources
• Timesharing
• Perform a small portion of one users job then
  move on to service the next user

17
Personal ComputingDistributed ComputingClient/Se
rver Computing

• Personal computers
• Economical enough for individual
• Distributed computing
• Organizations computing is distributed over
  networks
• Client/server computing
• Sharing of information, across computer
  networks, between file servers and clients
  (personal computers)

18
Types of Programming Languages

• Machine languages
• Strings of numbers giving machine specific
  instructions
• Example
• 130004277414005934191200274027
• Assembly languages
• English-like abbreviations representing
  elementary computer operations (translated via
  assemblers)
• Example
• LOAD BASEPAYADD OVERPAYSTORE GROSSPAY
• High-level languages
• Similar to everyday English, use mathematical
  notations (translated via compilers)
• Example
• grossPay basePay overTimePay

19
Some High-Level Languages

• Java used to
• Create web pages with dynamic and interactive
  content
• Develop large-scale enterprise applications
• Enhance the functionality of web servers
• Provide applications for consumer devices (such
  as cell phones, pagers and personal digital
  assistants)
• FORTRAN
• Used in scientific and engineering applications
• COBOL
• Used to manipulate large amounts of data
• Pascal
• Used to teach structured programming
• C/C
• Middle-level language
• Provides facilities for both high level as well
  as low level programming

20
History of C and C

• C evolved from C
• C evolved from two other programming languages,
  BCPL and B
• ANSI C
• Established worldwide standards for C programming
• C invented by Dennis Ritchie of ATT Bell Labs in
  the 1970s
• C by Bjarne Stroustrup of the same labs in the
  early 1980s
• C spruces up C
• Provides capabilities for object-oriented
  programming
• Objects are reusable software components that
  model things in the real world
• Object-oriented programs are easy to understand,
  correct and modify
• C is a subset of C

21
Structured Programming

• Structured programming
• Disciplined approach to writing programs
• Clear, easy to test and debug, and easy to modify
• Multitasking
• Many activities to run in parallel

22
Basics of a Typical C Environment

• Phases of C Programs
• Edit
• Preprocess
• Compile
• Link
• Load
• Execute

Files .cpp, .c, .h .obj, .exe

23
Errors

• Syntax errors
• reported by the compiler
• Linker errors
• reported by the linker
• Execution/Run-time errors
• reported by the operating system
• Logic errors
• not reported

24
Introduction to C Programming

• C language
• Facilitates a structured and disciplined approach
  to computer program design
• C and C are portable languages
• Programs written in C and C can run on many
  different computers

25
Identifiers in C

• A name assigned to
• A constant
• Variable
• Function
• User defined data type

26
Identifiers in C

• Rules
• Can be from one to several characters long
• First 1024 characters are significant
• May consist of alphanumeric and underscore
  characters
• May start with any letter of alphabet, or with an
  underscore
• Are case sensitive
• No special characters are allowed
• Spaces are not allowed as part of the identifier
  name
• Keywords cannot be used as identifiers
• Any other reserved words by the language (such as
  names of library functions) shall not be used as
  identifiers

27
Identifiers in C

• Conventions
• Use identifier names that reflect the meaning or
  usage of the items being named
• THISISACONSTANT or THIS_IS_A_CONSTANT
• thisisavariable or this_is_a_variable
• thisIsAFunction
• ThisIsAUserDefinedDataType