COMP103: Computer and Programming Fundamentals II Prof' Helen Shen helenscs'ust'hk

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COMP103 Computer and Programming Fundamentals
IIProf. Helen Shen lthelens_at_cs.ust.hkgt

• Course Web
• URL www.cs.ust.hk/course/comp103/

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Why are you taking COMP103?
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Are these your motivation?

• Because many people take it
• Just a random choice, no particular reasons
• A required course
• I failed COMP103 before I failed COMP104
• I got a good grade in COMP102
• Short lecture hours
• Want to be taught by a tough instructor and TAs
• Want to be taught by a pretty/handsome TA
• More

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I believe your REAL motivation is ...
I take it because I am interested
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Course Objectives

• Covers important, fundamental topics in
  structured programming
• Introduces object-oriented programming concepts.
• After this class, if you do a decent job in
  exams, and produce reasonable work which
  represents your own effort, you should be able to
  analyze a small problem and translate it into
  working computer code in terms of classes and
  objects.
• Through this class, we hope you can
• (1) develop the right mentality to solve a
  problem
• (2) excel at the right programming tool, such as
  C.

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Concepts to be covered

• The course is divided roughly into 4 parts
• 1st Review of basic programming
• And a Quiz on the topic ?
• 2nd Memory manipulation
• Pointers and memory address space
• Dynamic memory allocation
• 3rd Introduction to object-oriented programming
• Classes and Objects in C
• Data encapsulation and information hiding
• Abstract data types
• 4th Linked List Data Structure
• We will use memory management Class/Object
  tobuild a common data structure used by
  programmers the linked list

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Course Outline
Tentative Outline

• Programming Review (3 weeks) - Ch 2 to 8
• Pointers and Dynamic Memory (3 weeks) - Ch 9
• Class Objects (2 weeks) - Ch 10,11
• ADT OO Design (2 weeks) - Ch 12
• Linked-List, Searching Sorting (3 weeks) - Ch 17

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Assessment

• Labs 10
• Assignments 30 (two programming assignments)
• Quiz 10
• Midterm 20
• Final 30

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Resources

• Text book
• Computer Science - A Structured Approach using
  C, Forouzan Gilberg, second edition, Thomson
  Learning, 2004.
• This book has lots of C examples, it is highly
  recommended that you purchase it.
• Other resources
• Please refer to the course web page

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Teaching Assistants

• Teaching Assistants and Graders
• NG, Cherrie cherrie_at_cs.ust.hk
• Wong, David csdavid_at_cs.ust.hk
• Wu, Sally sallywu_at_cs.ust.hk
• -The TAs will provide you tutorial in labs and
  help you on assignments! They are your friends ?
• -The TAs have offices on campus (see webpage)
  which you can visit them. You can also send them
  e-mail to arrange meetings.

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Five Tips to Success
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Work hard
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Try more exercises and more practice
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Do the labs and assignments by yourself
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Be patient with the machine
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If you really need that, do it quietly ...
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Remember . . .

• This course is for you!
• Without the students the university wouldnt
  exist
• If you have questions, concerns (like the TA is
  not answering your email), or any suggestions,
  please let me (the instructor) know
• You can also always ask me questions via e-mail
  at (helens_at_cs.ust.hk)

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Your background for COMP103

• In this course, we assume that you have some
  programming background (e.g. COMP102)
• The following slides are a quick programming
  review
• Programming languages are all relatively similar,
  but their syntax can be different
• Example for loops in C and in Basic
• In C In Basic
• for(i0 i lt 10 i) for i1 to 10,
  step 1
• cout ltlt i ltlt endl print i
• If you dont know the exact syntax for C that
  is OK, there is always a C book you can refer
  to
• If none of the following slides seems familiar
  then you may consider taking a more basic
  programming course like COMP102

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Quick Programming Review

• Most programming languages provide the following
• Basic data types for variables
• integer, real, boolean, 1-D array, 2-D array
• Data operations (, , -, /, , , cin, cout,
  etc.)
• Flow control (sequential, branching, iteration)
• Function support (sometimes called sub
  routines)
• parameter passing by value, by reference
• recursive function
• As a programmer, you should exhibit
• Good programming methodology style

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Basic Data Structure (cont.)

• SIMPLE DATA TYPE in C
• Category Data types by size
• Character char, signed char, unsigned char
• Signed integer short, int, long
• Unsigned integer unsigned short, unsigned,
• unsigned long
• Floating point float, double, long double
• COLLECTION OF DATA
• 1-D Arrays, multi-D Arrays, Strings

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Data Operations

• Assignment operation
• , , -, , /, , , --
• Arithmetic operations
• , -, x, /
• Relational logical operations
• , !, gt, gt, lt, lt, ,
• Input/Output operations
• cout ltlt y, cin gtgt x
• File input/output operations
• InFile gtgt ch, OutFile ltlt ch

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Flow Control

• Simple Branching
• if (value lt 0)
• cout ltlt Number is negative
• else
• cout ltlt Number is positive

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Flow Control

• More complex Branching
• switch (month)
• case 9 case 4 case 6 case 11
• days_in_month 30
• break
• case 1 case 3 case 5 case 7 case 8 case
  10 case 12
• days_in_month 31
• break
• case 2 if (leap_year)
• days_in_month 29
• else
• days_in_month 28
• break
• default cout ltlt Incorrect value for
  Month.\n

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Flow Control (cont.)

• Iteration (while, for, do-while)
• cin gtgt next_value
• while (next_value gt 0)
• sum next_value
• cin gtgt next_value
• for (int counter 1 counter lt N counter)
• cout ltlt counter ltlt
• do
• cout ltlt Do it again?
• cin gtgt response
• while ((response Y) (response y))

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Function parameter passing

• int main ( )
• double x, y, sum, mean
• cout ltlt "Enter two numbers "
• cin gtgt x gtgt y
• sum_ave (x, y, sum, mean)
• cout ltlt "The sum is " ltlt sum ltlt endl
• cout ltlt "The average is " ltlt mean ltlt
  endl
• return 0
• void sum_ave(double no1, double no2, double sum,
  double average)
• sum no1 no2
• average sum / 2

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Function recursion

• int fac( int n ) // iteration version
• int product1
• while ( ngt1 )
• product n
• n--
• return product
• int fac( int n ) // recursive version
• if ( nlt1 ) // base case
• return 1
• else
• return n fac( n-1 )

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Good Programming Methodology

• Structured programming
• Program Goal
• Print out the following diamond pattern

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Good Programming Methodology (cont)

• Break the problem into sub-problems
• print out the upper half
• print out the lower half
• Think about how to solve the sub-problems
• Print out upper half
• row 1 print 4 spaces, 1 star
• row 2 print 3 spaces, 3 stars
• row 3 print 2 spaces, 5 stars
• row 4 print 1 space, 7 stars
• row 5 print 0 spaces, 9 stars
• Print out lower half
• row 4 print 1 space, 7 stars
• row 3 print 2 spaces, 5 stars
• row 2 print 3 spaces, 3 stars
• row 1 print 4 spaces, 1 star
  

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Good Programming Methodology (cont)

• Think of the logic and algorithms needed to
  realize the solutions to the problems
• Algorithm for upper half
• row 1 print (5-row)spaces, (2row - 1) stars
• row 2 print (5-row)spaces, (2row - 1) stars
  
• row 3 print (5-row)spaces, (2row - 1) stars
  
• row 4 print (5-row)spaces, (2row - 1) stars
  
• row 5 print (5-row)spaces, (2row - 1) stars
• Algorithm for lower half
• row 4 print (5-row)spaces, (2row - 1) stars
  
• row 3 print (5-row)spaces, (2row - 1) stars
  
• row 2 print (5-row)spaces, (2row - 1) stars
  
• row 1 print (5-row)spaces, (2row - 1) stars

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Good Programming Methodology (cont)

• // Translate your logic and algorithm to working
  code!!
• int row, space, star
• for(row1 rowlt5 row) //top half
• for(space1 spacelt5-row space)
• cout ltlt " "
• for(star1 starlt2row-1 star)
• cout ltlt ""
• cout ltlt endl
• for(row4 rowgt1 row--) //bottom half
• for(space1 spacelt5-row space)
• cout ltlt " "
• for(star1 starlt2row-1 star)
• cout ltlt ""
• cout ltlt endl

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Good Programming Style

• use functions extensively
• avoid global variables
• use reference arguments properly
• use functions properly
• handle errors properly
• avoid goto
• provide good documentation

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Good Documentation Style

• As a student, you often want to ignore
  documentation
• In a real company, where hundreds of programmers
  have to work together, documentation is very very
  important!
• Good documentation style include
• An initial comment for the program that includes
• statement of purpose
• author and date
• description of the programs input and output
• description of how to use the program
• assumptions such as the type of data expected
• statement of exceptions, that is, what could go
  wrong
• description of the key variables
• Initial comments in each function that state its
  purpose, preconditions, postconditions, and
  functions called

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Good Documentation Style

• Comments in the body of each function to explain
  important features or subtle logic
• Consistent Naming convention
• Function names begin with a lowercase letter
• Variables begin with a lowercase letter
• Words in multiple-words identifiers each
  separated by an underscore
• Named constants and enumerators are entirely
  uppercase and use underscores to separate words
• user-defined data types and names of structures,
  classes begin with an uppercase letter
• consistent indentation style

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Clean Coding Style
Your code should be readable by everyone!
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This is it

• If you feel comfortable with basic programming
  and want to learn more about C and
  object-oriented programming
• Welcome to COMP103 ?