Programming · Both
Algorithms & Computational Thinking
Before writing code, break the problem down and plan the steps. Examiners reward clear algorithmic thinking.
Key ideas
• **Decomposition** – split a problem into smaller parts
• **Abstraction** – focus on important details; ignore noise
• **Algorithm** – a precise sequence of steps to solve a problem
• Represent with **flowcharts** or **pseudocode**
Pseudocode habits
Use clear keywords: INPUT, OUTPUT, IF, ELSE, WHILE, FOR
Keep steps in order; indent selections and loops.
Test your logic with sample inputs before coding.
Worked example
Pseudocode: check if a mark is a pass (≥ 50)?
Solution: INPUT mark IF mark >= 50 THEN OUTPUT "Pass" ELSE OUTPUT "Fail" ENDIF
Practice questions
1. What is decomposition?
2. Name two ways to represent an algorithm.