Introduction to C++

1. F2037
PROGRAMMING
FUNDAMENTALS WITH C++

2. Information Systems
System
A collection of pieces working together to achieve a common
goal
An information system includes
Data, People, Procedure, Hardware/Software
System Development Life Cycle (SDLC)
An organized process (or set of steps) used to develop systems
in an orderly fashion

3. PROGRAM, PROGRAMMING & PROGRAMMER
• Program:
A set of step-by-step instructions that directs a
computer to perform a specific task and to produce the
required results.
• Programming:
Programming is a process of designing/ creating a
program.
• Programmer:
Programmer is a person who writes the program.

4. Problem Opportunity
Identification
Analysis
Design
Development &
Documentation
Testing & Installation
Maintenance & Evaluation
One step is completed before proceeding to the next
System Development Life Cycle

5. The Life Cycle of a Program
Programming is the process of translating a
task into a series of commands a computer will
use to perform that task.
Programming involves:
 Identifying the parts of a task the computer can perform.
 Describing tasks in a specific and complete manner
 Translating the tasks into a language that is understood by
the computer’s CPU.

6. Program Development Life Cycle
Step • Analyze Problem
1
Step • Design Programs
2
Step • Code Programs
3
Step • Debugging
4
Step • Formalize Solution
5
Step • Maintain Programs
6

7. Step 1 : Analyze Problem
The problem statement is:
 The starting point of programming
 A description of tasks the program is to accomplish
 How the program will execute the tasks
 Created through interaction between the developer and the
user
The program statement includes error handling
and a testing plan

8. What is involved in analyzing problem?
• Review program specifications
package
• Meet with systems analyst and users
• Identify each program’s input, output,
and processing components

9. Step 2 : Design Program
Develop an algorithm:
 A set of specific, sequential steps that describe what the
computer program must do
 Complex algorithms include decision points:
 Binary (yes/no)
 Loop (repeating actions)
 Visual tools used to track algorithm and decision points
include:
 Flowchart
 Pseudo Code
 Top Down design
 Object Oriented Analysis

10. Step 3 : Coding
Coding is translating an algorithm into a
programming language
Generations of programming languages

11. What is involved in coding programs?
Two Steps
Translating Entering
solution algorithm programming
into a programming language code into
language the computer

12. Step 4 : Debugging
Running a program to find errors is known as
debugging
Sample inputs are used to determine runtime
(logic) errors
Debugger: Tool that helps programmers locate
runtime errors

13. What is involved in testing programs?
Goal is to ensure program runs correctly and is
error free
Three types of errors
 Syntax
 Logic
 Run time

14. Syntax Errors
• Refers to an error in the syntax of a sequence of characters or
tokens that is intended to be written in a particular programming
language.
• For compiled languages syntax errors occur strictly at compile-
time. A program will not compile until all syntax errors are
corrected.
• For interpreted languages however syntax errors cannot be
detected until runtime and it is not necessarily simple to
differentiate a syntax error from a semantic error.
• A syntax error may also occur when an invalid equation is
entered into a calculator. This can be caused, for instance, by
opening brackets without closing them, or less commonly,
entering several decimal points in one number.

15. Logic Errors
• A logic error (sometimes called a semantic error) is a bug in a
program that causes it to operate incorrectly, but not to
terminate abnormally (or crash).
• A logic error produces unintended or undesired output or other
behaviour, although it may not immediately be recognized as
such.
• Logic errors occur in both compiled and interpreted languages.
• Unlike a program with a syntax error, a program with a logic
error is a valid program in the language, though it does not
behave as intended.

16. Run time Errors
• A runtime error is a computer error that appears in the form of a
message box consisting of a particular code along with its
corresponding definitions.
• Usually, a user will notice that the computer becomes
noticeably slow before a runtime error appears.
• After the runtime error message has been displayed and
closed, the software that shows this error would normally close
or freeze. In some cases, the operating system will reboot.
• A wide variety of errors cause these problems. These include:
• conflicts between the TSR (Terminate and Stay Resident Program)
• currently running applications
• software issues
• memory problems
• and harmful applications such as computer viruses

17. Step 5 : Formalize Solution
What is involved in formalizing solution?
Programmer performs two activities:
• Reviews program code
• Reviews documentation

18. Step 6 : Maintain Programs
What is involved in maintaining programs?
Identify
errors Identify
enhancements
Involves modifying existing programs
to improve their functionality

19. Programming language
Set of words, symbols, and codes that enables a programmer
to communicate a solution algorithm to the computer
Program Development Tool
User-friendly software products designed to assist in the
creation of information system solutions