1. (Course Introduction)
King Saud University
College of applied studies and community services
GC101
Computer Programming I
Lecture 1
(Course Introduction)

2. Lecture Outline What Is A Computer Program? Software? Why Program?
What Makes A Good Programmer?
An Overview of Computer Languages
History Of C
Why C?
Flow of Information During Program Execution
The Software Development Method
An Example of Meter to Yard Conversion
Algorithm
Pseudocode
Flowcharts
Course Introduction 1

3. What Is A Computer Program? Software?
Program = set of instructions that a computer will follow to
perform a specific task.
Software = collection of programs.
Two types of software:
System software: used to manage computer hardware to enable
us to execute & write application programs/software.
Ex. Operating System, Compilers, …etc.
Application Software: are meant for solving users own
problems. Ex. Word processors, database management…etc.
Course Introduction 2

4. Why Program? A tailor-made program is required.
Programmers are in high demand.
Programming is an intellectual challenge.
Course Introduction 3

5. What Makes A Good Programmer?
Two main factors:
Knowledge: data structures, algorithms, tools, when and how
to use those tools, & experience.
Maturity: patience, humility, & time management.
Only the first one can be taught.
Good programmers are more than 10 times productive as
average ones (does not mean they write 10 times as many
lines of code per day).
Course Introduction 4

6. An Overview Of Computer Languages
Machine Language Assembly Language High-Level Language
Collection of binary Symbolic form of machine Combines algebraic
numbers language (I.e. symbolic expressions & symbols taken
names are used to represent from English language
operations, registers & (ex. C, Pascal,
memory locations FORTRAN, …etc)
Ex. Ex. Ex.
MOV AX,A A = A + 4
ADD AX,4
MOV A,AX
Directly understood by a Assembler Compiler (or interpreter)
computer converts to machine converts to machine
language language
Easier to use
More powerful
Course Introduction 5

7. An Overview Of Computer Languages (Continue)
C is sometimes called a middle-level language.
This is not a reflection on its lack of programming power.
It’s a reflection on its capability to access the system’s low-level
functions.
Course Introduction 7

8. History Of C
Created by Dennis Ritchie at the Bell Telephone laboratories in
1972.
Evolved from a language called B.
Course Introduction 8

9. Why Use C?
C is a powerful and flexible language. C is used for projects as
diverse as operating systems, word processors, graphics,
spreadsheets, and even compilers for other languages.
C is a popular language preferred by professional programmers. As
a result, a wide variety of C compilers and helpful accessories are
available.
C is a portable language. Portable means that a C program written
for one computer system can be compiled and run on another
system with little or no modification (hardware independent).
Portability is enhanced by the ANSI standard for C, the set of rules
for C compilers.
Course Introduction 9

10. Why Use C?
C is a language of few words, containing only a handful of terms
called keywords, which serve as the base on which the language’s
functionality is built.
C is modular, C code should be written in routines called functions.
These functions can be reused in other applications or programs.
By passing pieces of information to the functions, you can create
useful, reusable code.
Course Introduction 10

11. The Software Development Method
1. Specify the problem requirements.
2. Analyze the problem.
3. Design the algorithm to solve the problem.
4. Implement the algorithm.
5. Test and verify the completed program.
6. Maintain and update the program.
Course Introduction 7

12. An Example of Meter to Yard Conversion
1. Specify the problem requirements
A program is required to convert square meters to square yards.
2. Analyze the problem
Problem Input:
Problem Output:
Formulas:
size in square meters (decimal)
size in square yards (decimal)
square yards = * square meters
3. Design the algorithm to solve the problem
1. Read the fabric size in square meters.
2. Convert the fabric size to square yards using the formula.
3. Display the fabric size in square yards.
Course Introduction 8

13. An Example of Meter to Yard Conversion
4. Implement the algorithm (i.e. write the program)
5. Test and verify the completed program.
6. Maintain and update the program.
Course Introduction 9

14. Algorithm
An Algorithm is a procedure for solving a problem in terms of:
1. the actions to be executed
2- the order in which these actions are executed
Course Introduction 10

15. Pseudocode
Pseudocode is an artificial and informal language that helps
programmer develop algorithms. It is similar to everyday English.
It is not a computer programming language.
Example
Get out of Bed
Take a shower
Get dressed
Eat breakfast
Drive to work
Course Introduction 11

16. Flowcharts
A flowchart is a graphical representation of an algorithm. They are
drawn using rectangles, diamonds, ovals, and small circles.
Course Introduction 12

17. Flowcharts (Continue)
Start or End
Input or Output
Process or Calculation
Decision
Course Introduction 13