Programming

Introduction
Topics
 Course introduction
 Problem solving and algorithm
 Program development steps
 Practice

Unit 1 - Programming / Lecture 1 - Introduction 2

Course introduction

 This unit introduces students to the core concepts of programming

with an introduction to algorithms and the characteristics of programming
paradigms
On successful completion of this unit students will be able to design and
implement a simple computer program in a chosen language (C#) within
a suitable IDE (Visual Studio .NET)

Unit 1 - Programming / Lecture 1 - Introduction 3

Learning outcomes
 LO1: Define basic algorithms to carry out an operation and outline the
process of programming an application.
 LO2: Explain the characteristics of procedural, object-orientated and
event-driven programming, conduct an analysis of a suitable Integrated
Development Environment (IDE)
 LO3: Implement basic algorithms in code using an IDE.
 LO4: Determine the debugging process and explain the importance of
a coding standard

Unit 1 - Programming / Lecture 1 - Introduction 4

Assignment for course
 Login to CMS
 Choose correct class
 Enroll by class name
CMS Folder:
o Assignment 1
o Assignment 2

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Course preparation
 Drawing tools (choose one):
o Visio
o Draw.io or Lucichart (online)
o Astah (recommendation, using student email to register full version)
 IDE
o Visual Studio Community 2017 or 2019

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COURSE READING
 Learning materials on FLM
o https://flm.greenwich.edu.vn/
 C# 6.0 and .NET Framework 4.6
o http://library.books24x7.com/toc.aspx?bookid=104367
o Registered with student email
 Mohammad Rahman, Expert C#5.0 with .NET 4.5 Framework

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Problem solving
 It’s a creative process, it is an act of
o Defining a problem
o Determining the cause of the problem
o Identifying, prioritizing, and selecting alternative for a solution
o Implementing a solution

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 Algorithm
 An algorithm is a step-by-step description of the solution to a problem.
 Characteristics of an Algorithm
o Definiteness: Each step must be precisely defined; the actions to be carried out must be rigorously
and unambiguously specified for each case
o Finiteness: The algorithm must always terminate after a finite number of steps.
o Precise and Effective: All operations to be performed must be sufficiently basic that they can be
done exactly and in finite length.
o Implementation independent: An algorithm should have step-by-step directions, which should be
independent of any programming code

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Algorithm
 Example of Algorithms in Programming
Algorithm to add two numbers entered by the user
Step 1: Start
Step 2: Declare variables num1, num2 and sum.
Step 3: Read values num1 and num2.
Step 4: Add num1 and num2 and assign the result to sum.
sum = num1+num2
Step 5: Display sum
Step 6: Stop

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Steps in Program Development

The various steps involved are

o Defining or Analyzing the problem
o Design (Algorithm)
o Coding
o Documenting the program
o Compiling and running the program
o Testing and Debugging
o Maintenance

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STEPS IN Program Development:
1. Analyzing or Defining the Problem
The problem is defined by doing a preliminary investigation
Defining a problem helps us to understand problem clearly
It is also known as Program Analysis

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Tasks in defining a problem

 Followings are the tasks in order to

define a problem
o Specifying the input requirements
o Specifying the output requirements
o Specifying the processing requirements

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Specifying the input requirements
The input specification is obtained by answering following questions
o What specific values will be provided as input to the program?
o What format will the values be?
o For each input item, what is the valid range of values that it may assume?
o What restrictions are placed on the use of these values?

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Specifying the output requirements
The output specification is obtained by answering the following questions
o What values will be produced?
o What is the format of these values?
o What specific annotation, headings, or titles are required in the report?
o What is the amount of output that will be produced?

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Specifying the processing requirements
The processing requirement is obtained by answering following questions
o What is the method (technique) required in producing the desired output?
o What are the validation checks that need to be applied to the input data?
o What calculations are needed?

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Activity: Find Factorial Number
Input?
Output?
Process?

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Activity Find Factorial Number
Input: Positive integer number
Output: Factorial of that number
Process: Solution technique which transforms input to output. Factorial of a
number can be calculated by the formula n!=1*2*3*…*n

Unit 1 - Programming / Lecture 1 - Introduction 18

Use-case diagram
Use case diagrams are used to gather the requirements of a system
So when a system is analyzed to gather its functionalities, use cases are
prepared and actors are identified.
The purposes of use case diagrams can be as follows:
o Used to gather requirements of a system
o Used to get an outside view of a system
o Identify external and internal factors influencing the system
o Show the interacting among the requirements are actors

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Main elements of use-case diagram

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Activity: Draw use-case diagram
You are hired to develop FAI’s library system with following description
- Admin who could
- Manage books, readers (staff, lecturers, and students), etc.
- Manage borrow/return books
- Users (staff, lecturers, students) who could
- View/search books
- Reserve books
- Borrow/return books
Please draw Use-case diagram for this scenario
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STEPS IN Program Development:
2. Design
A design is the path from the problem to a solution in code
The well designed program is likely to be:
o Easier to read and understand later
o Less of bugs and errors
o Easier to extend to add new features
o Easier to program in the first place

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Modular Design
Once the problem is defined clearly, several design methodologies can be
applied
An important approach is Top-Down program design
It is structured design technique
o It breaks up the problem into a set of sub-problems called Modules
o It creates a hierarchical structure of the modules

Unit 1 - Programming / Lecture 1 - Introduction 23

Flowchart
Flowchart is a diagrammatic representation of an algorithm
It uses different symbols to represent the sequence of operations, required to
solve a problem
It serves as a blueprint or a logical diagram of the solution to a problem

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Flowchart symbols (1/2)

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Flowchart symbols (2/2)

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Activity: Drawing flowchart
 Draw a flowchart for the algorithm to find factorial number in
previous activity

Unit 1 - Programming / Lecture 1 - Introduction 27

STEPS IN Program Development:
3. Coding
 An algorithm expressed in programming languages is called Program
 Writing a program is called Coding
 The logic that has been developed in the algorithm is used to write program

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STEPS IN Program Development:
4. Documenting the Program
 Document explains
o How the program works and how to use the program (user manual)
o How to maintain the program (developer manual)
 Details of particular programs, or particular pieces of programs, are easily for
gotten or confused without suitable documentation

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Forms of documentation
Documentation comes in two forms
o External documentation, which includes things such as reference manuals, algorithm
descriptions, flowcharts, and project workbooks
o Internal documentation, which is part of the source code itself (essentially, the
declarations, statements, and comments)

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STEPS IN Program Development:
5. Compiling and Executing the Program
Compilation is a process of translating a source program into machine
understandable form
The compiler is system software
o It examines each instruction for its correctness
o It does the translation
During the execution
o Program is loaded into the computer’s memory
o The program instructions are executed

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STEPS IN Program Development:
6. Testing and Debugging
Testing is the process of executing a program with the deliberate intent of
finding errors
Testing is needed to check whether the expected output matches the actual
output
Testing is done during every phase of program development
Initially, requirements can be tested for its correctness
Then, the design (algorithm, flow charts) can be tested for its exactness and
efficiency

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Test criteria
Programs are tested with several test criteria and the important ones are
given below
o Test whether each and every statement in the program is executed at least one (Basic
path testing)
o Test whether every branch in the program is traversed at least once (control flow)
o Test whether the input data flows through the program and is converted to an output
(data flow)

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Significant test cases
Significant test cases increase the possibility to discover bugs.
It is important to design test cases for abnormal input conditions
o The boundary (or extreme) cases
o The unusual cases
o The invalid cases

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STEPS IN Program Development:
6. Testing and Debugging
 Debugging is a process of correcting the errors
o Programs may have logical errors which cannot be caught during compilation
o Debugging is the process of identifying their root causes
o One of the ways is to print out the intermediate results at strategic points of
computation
o Another way is to use support from the IDE
 Testing vs Debugging
o Testing means detecting errors
o Debugging means diagnosing and correcting the root causes

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STEPS IN Program Development:
7. Maintenance
 Program maintenance
o Continuing process of maintenance and modification
o To keep pace with changing requirements and technologies
 Maintainability of the program is achieved by
o Modularizing it
o Providing proper documentation for it
o Following standards and conventions (naming conventions, using symbolic constants,
etc.)

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INTRODUCTION TO PROGRAMMING LANGUAGE

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What is a Programming Language?
It is an art of making a computer to do the required operations
o By means of issuing sequence of commands to it
It can be defined as
o A vocabulary (unique set of characters/keywords)
o A set of grammatical rules (syntax)
The term programming languages usually refers to high-level languages
o E.g., BASIC, C, C++, COBOL, FORTRAN, Ada, and Pascal

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Types of programming languages

There are two major types of programming languages

o Low level languages (LLL)
o High level languages (HLL)

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What makes a good language?
Every language has its strengths and weaknesses
FORTRAN is good for numeric data but not good to organize large program
PASCAL is good for structured and readable programs, but it is not as flexible
as C
C++ has powerful object-oriented features, but it is complex and difficult to
learn
The choice of PL depends on type of the computer used, type of program,
and the expertise of the programmer

Unit 1 - Programming / Lecture 1 - Introduction 40

Development Environments
Programming on Host Environment:
o The environment under which a program is designed, coded, tested and debugged
Operating on Target Environment
o The external environment which supports the execution of a program Target

Hello.c Hello.exe
Hello.exe
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Summary
 Draw a mind-map to summarize the content of this lecture

Unit 1 - Programming / Lecture 1 - Introduction 42

Install Visual Studio - IDE
 Install Visual Studio 2019
https://visualstudio.microsoft.com/vs/

Unit 1 - Programming / Lecture 1 - Introduction 43