Mainline and subroutines (algorithms)

Diagram

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Definition

Start complex algorithms with a clear, uncluttered mainline that calls subroutines; the details of each subroutine are in separate algorithms.

Example: BEGIN Main: GetData, Process, Display END.

Found in: syllabus, course specifications, school notes.

Where you'll use it in the test

Syllabus area: Diagrams and tools.

Question types it can appear in

Pseudocode: Use it correctly in the exam pseudocode editor.
Drawing: Draw or label it in the online drawing tool.
Short answer: Define, outline or explain it and tie it to the scenario.

Where it has appeared in the paper

The Software Engineering Project (Part B). Part letters follow each paper’s own layout.

How to use it

A model sentence

General advice, built from the definition and example above

Diagram: “Start complex algorithms with a clear, uncluttered mainline that calls subroutines; the details of each subroutine are in separate algorithms.” Then apply it: BEGIN Main: GetData, Process, Display END.

In a short answer, give the definition in your own words first, then tie it to the situation in the question. Do not copy the example above unless it fits the scenario.

Command words used with it

General advice

No linked question shows the command word for this term. Across the past pseudocode and drawing and short answer questions in this bank the words used most are: Explain, Outline, Describe, Compare, Classify, Analyse. Check the actual word in your question.

Official worked answer

Sample exam Q14 (3 marks): Algorithm design (subroutines) (3 marks): official criteria and sample answer

Criteria

3: Substantially correct pseudocode that includes at least ONE subroutine. 2: Addresses some of the requirements. 1: Some understanding of the problem.

Sample answer

BEGIN main Get num_pizzas total_cost = 0 FOR i = 1 TO num_pizzas Get pizza_size Get num_toppings cost_per_pizza = calculate_pizza_cost(pizza_size, num_toppings) DISPLAY cost_per_pizza total_cost = total_cost + cost_per_pizza NEXT i DISPLAY total_cost END main

BEGIN calculate_pizza_cost(size, num_toppings) base_price = 10 topping_price = 1.5 IF size = "Medium" THEN base_price = base_price + 2 ELSEIF size = "Large" THEN base_price = base_price + 4 ENDIF pizza_cost = base_price + num_toppings * topping_price RETURN pizza_cost END calculate_pizza_cost

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Flashcard: Mainline and subroutines (algorithms) in Diagrams and Modelling Tools (Years 11 and 12) · study that set
Memorise: Drawing rules: DFD, structure chart, storyboard, decision tree, class diagram, ERD
Full term page: every question, note and marking comment for Mainline and subroutines (algorithms)

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