Reusable Code Blocks

Part of Bubble Sort · Section 2 of 9

IntroductionUnit: 3.1 Fundamentals of AlgorithmsGCSE

This introduction covers Reusable Code Blocks within Bubble Sort for GCSE Computer Science. Revise Bubble Sort in 3.1 Fundamentals of Algorithms for GCSE Computer Science with 16 exam-style questions and 10 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 2 of 9 in this topic. Use this introduction to connect the idea to the wider topic before moving on to questions and flashcards.

Reusable Code Blocks

Imagine writing instructions for making tea. Instead of writing "boil water" every time, you could say "see 'boiling water' instructions on page 5". Subprograms (functions and procedures) work the same way - write code once, use it many times by "calling" it. Functions return a value (like a vending machine giving you a drink). Procedures just do something (like pressing a button that turns on a light).

Practice questions for Bubble Sort

Which of the following best describes bubble sort?

  • A. It selects the smallest element and moves it to the front each pass
  • B. It compares adjacent elements and swaps them if they are in the wrong order
  • C. It divides the list in half repeatedly until each half is sorted
  • D. It inserts each element into its correct position one at a time
1 markfoundation

Describe how bubble sort works. You should refer to what happens during each pass through the list. [3 marks]

3 marksstandard

Quick recall flashcards

Why is it called bubble sort?
Largest values bubble up to the end like bubbles rising in water
How does bubble sort work?
Compare adjacent pairs, swap if wrong order, repeat passes

16 questions on Bubble Sort — practise free

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