ekt150 introduction to computer programming introduction to computer and computer programming dr....
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EKT150 INTRODUCTION TO COMPUTER PROGRAMMING
Introduction to Computer and Computer Programming
Dr. Nik Adilah [email protected].
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• Contributes 3 units:– 2 hours lectures– 2 hours labs
• Main Objective:– Students can independently write, read, compile, debug
and execute computer programs to solve problems, especially engineering related problems.
COURSE INFORMATION
COURSE OUTCOME
1. Ability to define and describe programming concepts and principles.
2. Ability to apply GNU/Linux for coding, compiling, executing and debugging computer programs.
3. Ability to analyze and solve engineering related problems using computer programming techniques
4. Ability to evaluate programming techniques and tools to design computer programs.
ASSESSMENT
• 4 main components:– Theoretical Tests 20%– Lab Assignments 20%– Lab Test 10%– Final Exam 50%
• Assignments are assessed individually (in lab assignment) • Theoretical tests are written tests• Attendances are compulsory!
REFERENCES
• Deitel & Deitel, “C How to Program”, International Edition, Pearson-Prentice Hall, 2010.
• Cheng, H., “C for Engineers and Scientists”, McGraw Hill, 2010.
• Hanly, J.R. and Koffman, E.B., “C Program Design for Engineers”, 2nd Ed., Addison-Wesley, 2001.
ISBN : 0321204174
NOTES
• This course is NOT about the language per se, it is about analytical skills and to apply programming to solve problems.
• Write C program in Linux environment/GNU compiler applications
• Do early reading• Do not hesitate to ask during lecture sessions
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LECTURE OUTLINE
1. Introduction to Computer
2. Introduction to Computer Programming
3. Introduction to C Programming Language
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A Brief Look At Computer Computer
is a device that receives input, stores and processes data, and provides output in a useful format.
Computers process data according to sets of instructions called computer programs
Example: laptops, PCs, mainframes, mobile phones, washing-machines, TV sets, cars contain computers
Hardware Physical components of a computer Example: Keyboard, screen, mouse, disks, memory, CD-ROM, and
processing units
Software Programs that run on a computer Example: Operating System such as windows XP -Vista -7, Word
processing packages such as MS Word, registration program
Computer Hardware
Exercise: Distinguishing between input-process and output-storageThe scenario: “At the end of each month, a clerk enters the employee name, number of days present and absent, and the number of overtime done in the system. The system then calculates the normal salary, the amount for overtime and the total salary. The clerk then saves the information in the computer hard disk, and takes a backup on a cd. A report is produced for the clerk to be shown to the manager. “
Task: Identify the following for that particular system
1. Input2. Process(es) 3. Output4. Storage
Exercise: Distinguishing between input-process and output-storageThe scenario: “At the end of each month, a clerk enters the employee name, number of days present and absent, and the number of overtime done in the system. The system then calculates the normal salary, the amount for overtime and the total salary. The clerk then saves the information in the computer hard disk, and takes a backup on a cd. A report is produced for the clerk to be shown to the manager. “
Task: Identify the following for that particular system
1. Input: the employee name, number of days present and absent, the number of overtime
2. Process(es): calculate normal income, calculate amount for overtime, calculate total salary
3. Output: Report4. Storage: Harddisk, CD-ROM
How Computer Processes Information?
Computers are NOT intelligent Computers do what we tell them to do they don’t do anything by
themselves. We must clearly tell a computer what to do in a step by step
manner using a programming language.
Computers only understand “electronic” High voltage/low voltage – The machine language Machine language is binary (two values: high/low) 1’s and 0’s
Why We Use Computer?
• Computers produce fast, accurate and reliable results.• While computers do the boring, repetitive, ordinary tasks, we can
spend our efforts and time to work on more interesting and creative tasks.
• The use of computers in business and manufacturing decreases the cost of goods and services produced.
• It is more difficult and needs more time to find or grow up a skill-full labour in IT industry, while buying an additional computer and installing the required software on is easier and cheaper.
INTRODUCTION TO COMPUTER PROGRAMMING
Programming / Program / Programmer
• Programming in general term is planning or implementation of a task or event command. In the computing field, is instructing a computer to perform specific tasks.
• Computer programming can be defined as the process of planning a set of sequence commands to be executed by a computer.
• Program be defined as a set of sequence commands that have been determined to be executed by a computer.
• Computers are just electronic devices that have the power to perform difficult tasks but they do not ‘KNOW’ what to do therefore - programmers tell the computers what to do by writing programs
Types of Programming Languages Machine language
Strings of numbers giving machine specific instructions
Example: +1300042774, +1400593419, +1200274027
Assembly language English-like abbreviations representing
elementary computer operations (translated via assemblers)
Example: LOAD BASEPAY, ADD OVERPAY High level language
Codes similar to everyday English. Use mathematical notations (translated via compilers)
Example Code: grossPay = basePay + overTimePay
Example high level languages: C, C++, Java
Programming Problem
• Problem that can be solve using programming language.• Suppose you want to add 34 and 56, this is easy. But to add 100 numbers is
difficult for us need to use calculator or paper and pencil. Or we can write a program for computer to help us.
• Can these problems solve by computer programming?• Converting units from kilograms to grams.• Counting the number of cars on a highway.• Finding a life partner• Total rain in a week• How long we live• What we want to eat for dinner
Problem Solving using Programming
Steps of Programming1. Requirement Specification: Eliminate ambiguities, Clearly
understand the problem
2. Analyse the problem: Understand the inputs, outputs and processes used for manipulating the data, formulas and constraints
3. Design: Write the algorithm (flowchart or pseudocode) to represent the solution
4. Implement the algorithm: Write a program
5. Testing and Verification: Check the program
6. Documentation
Properties of Well Designed Programs
Well designed programs must :
Correct and accurate
Easy to understand
Easy to maintain
and update
Efficient Reliable Flexible
INTRODUCTION TO C PROGRAMMING LANGUAGE
Programming Basics
• Computer programs are a detailed set of instructions given to the computer
• Programs are constructed based on an ALGORITHM which is an outline of how your computer program will work
• Algorithms are a problem solving procedure that consist of:
1. What actions you want the computer to perform2. The order of those actions should happen in
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Creating Algorithms• To solve problem using algorithms, we have to:
–READ and understand the problem–THINK about different solutions to the
problem–DESIGN an approach that will solve the
problem– IMPLEMENT that design–TEST to see if it works
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If needed
Form of Algorithms
• The constructs used to build algorithms can be described in two different ways:1. Pseudo code2. Flowchart
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1. Pseudo Code
• When the algorithm is written out as a well-thought series of steps, it is called PSEUDO CODE• It is written in easy to understand language (i.e.
ENGLISH)• It is written very similar to the way that you would code
it into your 3rd Generation Language (i.e. C Language)
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Example 1: Pseudo Code• Create a detailed set of instructions
(pseudo-code) that will tell us:– How to eat a banana
• Make your instructions as detailed as possible, so that even someone who has never eaten a banana before can understand them
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INSTRUCTIONS OF HOW TO EAT A BANANA:
1. Using your hand, get a yellow crescent-shaped fruit called a “banana”
2. Peel the outer skin off the banana
3. Eat the bananai. Put a small section of banana in your mouthii. Bite down on the bananaiii. Chew the banana by opening and closing your mouthiv. Once the banana has been chewed, swallow the bananav. Repeat until banana is finished
4. Throw out the used banana peel27
Example 1: Pseudo Code
RESULT• Mak Minah arrives in a great
mood ready to work
RESULT• Mak Minah arrives in not too
great a mood since she’s soaking wet
WAKE UP MAK MINAH 1• Get out of bed• Take off pyjamas• Take a shower• Get dressed• Eat breakfast• Drive to school
WAKE UP MAK MINAH 2• Get out of bed• Take off pyjamas• Get dressed• Take a shower• Eat breakfast• Drive to school
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Example 2: Pseudo Code
The order of actions are very
important!
2. Flow Chart
• The algorithm can also be written as a FLOW CHART• The flow chart is a graphic organiser (a picture that
helps organize your thoughts) • It uses a collection of basic symbols that are used to
organize your algorithm• These symbols are connected by arrows that show
how the algorithm “flows”
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Visual Form of Flow Chart• Flowchart: visual-form of an algorithm Example:
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Process 2Decision
Input Data
Process 1
Begin
Output Result
End
Algorithms: Flow Chart• BASIC SYMBOLS IN FLOW CHART
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TERMINAL: Start/End of a program
PROCESSING: shows any mathematical operation (e.g. addition, substraction, etc)
INPUT/OUTPUT: – where the user of the program is asked for information (INPUT) or where the program displays a result (OUTPUT)
DECISION: represents any action where the computer is making a decision
Flow direction
Algorithms: Pseudo Code & Flow Chart
Example 1• Write an algorithm that display a message to the screen as
“Hello World!”.
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• Begin• Print Message• End
Begin
Print “Hello World!”
End
Pseudo Code Flow Chart
Example 2:Write a flowchart that calculates and prints the SUM of two integers A and B.
• Begin• Input A and B• Calculate A + B• Print result of SUM• End
Begin
Input A, B
Calculate A + B
Print SUM
End
Pseudo Code Flow Chart
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Algorithms: Pseudo Code & Flow Chart
Exercises
1) Write an algorithm (pseudo code and flow chart) to read input of 3 test marks, calculate the average and display the final marks.
2) Additional to (1), if the final marks is 60 and above, display mark and “Passed”, otherwise display mark and “Failed”.
• Begin• Input test1, test2 and test3• Calculate average• Print result of average• End
Begin
Input test1,test2 & test3
Calculate average= (test1+test2+test3)/3
Print Average
End
Pseudo Code Flow Chart
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Answer Exercise (1)
• Begin• Input test1, test2 and test3• Calculate average• If average >=60
• Display average & “Passed”• Otherwise
• Display average & “Failed”• End
Pseudo Code Flow Chart
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Answer Exercise (2)
Begin
Input test1,test2 & test3
Calculate average= (test1+test2+test3)/3
Average >= 60
Display average and “Passed”
Display average and “Failed”
End
True False
References
1) Yuksel Uckan, “Problem Solving Using C, Structured Programming Techniques”, McGraw-Hill
2) Deitel and Deitel, C: “How to Program”, McGraw-Hill
3) Cheng, H., “C for Engineers and Scientists”, McGraw Hill, 2010
4) Hanly, J.R. and Koffman, E.B., “C Program Design for Engineers”, 2nd Ed., Addison-Wesley, 2001, ISBN : 0321204174