C Programming Technique – Firdaus-Harun.com Pseudocode

Agenda Intro to Pseudocode Pseudocode vs Flowchart Technique – Write pseudocode Examples

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

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

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 »]

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]

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

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

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

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

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

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

Example 2 (Selection) Read A, B - Input BIG = B - Action 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

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

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.

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.

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 : ………………………..