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Logic Points 0 / 32
Algorithmist Rank Logic Novice

Topic 2.1: Computational Thinking

Core concepts: Decomposition, Abstraction, and Algorithmic Thinking.

1 [3 Marks]
Match the term to the correct definition.
Abstraction
Decomposition
Algorithmic Thinking
✅ Mark Scheme

Abstraction: Filtering out unnecessary details (C).

Decomposition: Breaking down a complex problem (A).

Algorithmic Thinking: Logical steps to solve a problem (B).

Score:
2 [4 Marks]
Sat-nav calculating route from London to Manchester.
(a) Essential Info (2 marks)
(b) Irrelevant Info to remove (Abstraction) (2 marks)
Think: "What does the MATH need?" Distance? Speed? Yes. Colour of the car? No.

(a) Essential:

(b) Irrelevant (remove):

✅ Mark Scheme

(a) Essential: Current Location, Destination, Speed limits, Traffic, Map data.

(b) Irrelevant: Car colour, Passengers, Weather (mostly), Building shapes, Music.

Score:
3 [2 Marks]
Define Decomposition.
"De-compose" = "Take apart". Think helping a big problem become smaller problems.
✅ Mark Scheme

Breaking down a complex problem (1) into smaller, manageable parts (1).

Score:
4 [5 Marks]
Structure Diagram: SportsDaySystem.
Tasks: 1. Register, 2. Record, 3. Display.
Sub-tasks: (InputName, AssignHouse), (EnterTime, CalculatePoints), (ShowHouseWinner, PrintCertificates).
Diagram looks like a family tree. Top: System Name. Middle: 3 Main Tasks. Bottom: Sub-tasks connected to their parent.

Describe your diagram structure or list the hierarchy:

✅ Mark Scheme
  • Level 1: SportsDaySystem (Top)
  • Level 2: Register, Record, Display (connected to top)
  • Level 3 (under Register): InputName, AssignHouse
  • Level 3 (under Record): EnterTime, CalculatePoints
  • Level 3 (under Display): ShowHouseWinner, PrintCertificates
Score:
5 [3 Marks]
"Alien Attack" Game Loop Decomposition. Fill in the blanks.
1. CheckPlayerInput
2. ______________ (Moving characters)
3. ______________ (Checking death)
4. UpdateScore
✅ Mark Scheme

Branch 2: UpdatePositions / MovePlayer / MoveEnemies

Branch 3: CheckCollision / CheckGameOver / CheckLives

Score:
6 [4 Marks]
Explain two benefits of using Decomposition for large programs.
Think about: Teamwork (can you split work?) and Debugging (is it easier to find bugs in small bits?).
✅ Mark Scheme
  • Teamwork: Different people can work on different parts simultaneously (2).
  • Debugging: Easier to locate errors in smaller modules (2).
  • Reusability: Modules can be reused in future programs (2).
Score:
7 [3 Marks]
Program to calculate Area of Rectangle.
Identify Input, Process, Output.
✅ Mark Scheme

Input: Length AND Width.

Process: Area = Length * Width.

Output: Area / Result.

Score:
8 [4 Marks]
State the Flowchart Symbol Name for each:
start()
count = count + 1
if score > 10
print(total)
✅ Mark Scheme
  • start(): Terminator / Start/Stop
  • calculation: Process / Box
  • if: Decision / Diamond
  • print: Input/Output / Parallelogram
Score:
9 [4 Marks]
Pseudocode Task: Smart Thermostat.
- If temp < 18, Heating ON.
- If temp > 21, Heating OFF.
- Otherwise no change.
Logic Structure Hint:
if temp < 18 then
  ...
elseif ... then
  ...
endif
✅ Mark Scheme
if currentTemp < 18 then
  heating = "ON"
elseif currentTemp > 21 then
  heating = "OFF"
endif

1 mark for correct inputs/reading.
1 mark each for correct conditions.
1 mark for correct structure (IF/ELSEIF).

Score:
10 [3 Marks]
Why is Abstraction necessary for a Flight Simulator game?
✅ Mark Scheme
  • Computers have limited processing power (1).
  • Too much detail (e.g. cloud physics) slows it down (1).
  • Focus only on what matters (flight mechanics) for the game purpose (1).
Score: