Introduction to computer

1. +
Ramadan Babers
Introduction
to
Computer
LEC - 4

2. +
Algorithm
2

3. Chapter 4 Outlines
 Introduction
 Examples
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4. Introduction
Algorithm is a set of mathematical instructions or rules
that, especially if given to a computer, will help to calculate
an answer to a problem.
4

5. Example (1)
Write the algorithm and draw the flow
chart that calculate the area of a rectangle,
given the length (L) and width (w).
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Algorithm:
Step 1 : input first number
Step 2 : input second number
Step 3 : multiply two numbers and
store result in Area
Step 4 : print Area

6. Example (2)
Write the algorithm and draw the flow chart that Determine the state of a
student (failed or succeeded) depending on his/her score in the exam
(full mark is assumed to be 100).
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Algorithm:
Step 1 : input the score
Step 2 : check if the score is less
than 50 if yes go to Step 3
else go to Step 4
Step 3 : print Failed
Step 4 : print Succeeded

7. Example (3)
Write the algorithm and draw the flow chart that Print Numbers from 1
to 100
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Algorithm:
Step 1 : take an initial number i=1
Step 2 : print the i
Step 3 : add 1 to i
Step 4 : check if i is less than or
equal 100 if yes go to Step
2 else stop

8. Required
• Write the algorithm and draw the flow chart that
print odd numbers from 1 to 100
• Write the algorithm and draw the flow chart that
print a sequence of numbers and their squares,
starting from one to M where M is an input.
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9. + Programming
Language
9

10. Chapter 5 Outlines
 Evolution
 Categories of programming languages
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11. Evolution
 To write a program for a computer, we must use a
computer language.
 A computer language is a set of predefined words that
are combined into a program according to predefined
rules (syntax).
 Over the years, computer languages have evolved from
machine language to assembly languages to high-level
languages.
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12. Programming Language
Programming language: A set of rules, words, symbols, and
codes used to write computer programs
 To write a program, you need appropriate software for the
programming language you will be using
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13. Categories of programming languages
 Low-level languages: Difficult to code in; machine dependent
 Machine language: 1s and 0s
 Assembly language: Includes some names and other
symbols to replace some of the 1s and 0s in machine
language
 High-level languages: Closer to natural languages
 Machine independent
 Visual or graphical languages: Use graphical interface to
create programs
 Fourth-generation languages (4GLs): Even closer to natural
languages and easier to work with than high-level
 Declarative rather than procedural
 Includes structured query language (SQL) used with
databases
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