1. C Programming Technique – Firdaus-Harun.com Pseudocode

2. Agenda • Intro to Pseudocode • Pseudocode vs Flowchart • Technique – Write pseudocode • Examples

3. What’s Pseudocode ? • Artificial and Informal language • Helps programmers to plan an algorithm • Similar to everyday English • Not an actual programming language

4. E.g : Pseudocode Read A, B Calculate C = A*B Display C Stop

5. Technique • Do not write Start in every pseudocode • Parallelogram – Read / Get OR Display / Print • Rectangle – Specify the actions • E.g: • Calculate A = B + C OR A equals to B plus C • Average = total / count • Final price equals price of item plus sales tax • Diamond – [Next »]

6. Technique (..Cont.) • Diamond • Selection – IF , IF / ELSE and IF / ELSE IF IF A is less than B BIG = B SMALL = A ELSE BIG = A SMALL = B • Repetition – WHILE / DO/WHILE / FOR [Next example]

7. Comparative Between Flowchart vsPseudocode • Flowchart • A graphical way of writing pseudocode • Rounded rectangle – terminal • Parallelogram – input / output • Rectangle – actions • Diamonds – decision / conditional • Circles – connector

8. Start Terminal. Program start here Stop Terminal Program end here Input. Enter values for A and B Process Output E.g : Flowchart

9. Comparative Between Flowchart vsPseudocode (..Cont.) • Pseudocode • No syntax rule – Independent from any programming language • Write in an ordinary language • Uses a structure resembling computer structure • No connector between pages

10. E.g : Pseudocode Read A, B Calculate C = A*B Display C Stop

11. E.g : Pseudocode Read A, B – Input Calculate C = A*B - Action Display C - Output Stop - Terminal

12. Example 2 (Selection) Read A, B IF A is less than B BIG = B SMALL = A ELSE BIG = A SMALL = B Write / Display BIG, SMALL Stop

13. Example 2 (Selection) Read A, B - Input IF A is less than B - Selection BIG = B - Action SMALL = A - Action ELSE - Selection BIG = A - Action SMALL = B - Action Write / Display BIG, SMALL - Output Stop - Terminal

14. Example 3 (Repetition) Set count to zero Set total to zero Read number WHILE ( not end-of-data ) increment count by 1 total = total + number read number IF ( count > 0 ) then average = total / count Display average Stop

15. Advantages • Converting a pseudocode to a programming language is much more easier than converting a flowchart. • As compared to flowchart, it is easier to modify a pseudocode of a program logic when program modifications are necessary.

16. Limitations • In the cases of pseudocode, a graphic representation of program logic is not available. • There are no standard rules to follow for using a pseudocode. • Different programmers use their own style of writing pseudocode; and hence, • Communication problem occurs due to lack of standardization.

17. Class Tutorial • *Using previous Flowchart tutorial. • Write a pseudocode to calculate Area and Perimeter of a trapezoid. • Write an algorithm to set a Median for given number : ………………………..