2.2.2a Problem recognition, decomposition, divide and conquer, abstraction Quiz: OCR Computer Science, Unit 7

The 20 questions

1. What is the process of removing unnecessary details to focus on essential characteristics?

   • Encapsulation
   • Abstraction
   • Generalisation
   • Decomposition

2. What term describes breaking down a complex problem into smaller, more manageable sub-problems?

   • Pipelining
   • Abstraction
   • Decomposition
   • Backtracking

3. Which algorithmic strategy repeatedly splits a problem, solves sub-problems, and combines their solutions?

   • Greedy approach
   • Dynamic programming
   • Heuristic search
   • Divide and conquer

4. What is the initial stage of identifying a real-world issue that requires a computational solution?

   • System testing
   • Problem decomposition
   • Requirements analysis
   • Problem recognition

5. What type of model simplifies a real-world system by discarding non-essential physical features?

   • Concrete model
   • Abstract model
   • Dynamic model
   • Physical model

6. What is the typical time complexity of a standard binary search using divide and conquer?

   • O(log n)
   • O(n^2)
   • O(1)
   • O(n)

7. Which software design methodology uses decomposition to break high-level tasks into detailed sub-routines?

   • Agile development
   • Object-oriented design
   • Bottom-up design
   • Top-down design

8. What type of abstraction hides the specific implementation details of a calculation behind a function call?

   • Data abstraction
   • Representational abstraction
   • Procedural abstraction
   • Control abstraction

9. A subway map shows station connections but ignores precise geographical distances. What technique is this?

   • Decomposition
   • Simulation
   • Caching
   • Abstraction

10. A developer splits a shopping application into user login, payment processing, and inventory modules. What is this?

    • Virtualisation
    • Divide and conquer
    • Data abstraction
    • Decomposition

11. Which searching or sorting algorithm relies directly on the divide and conquer computational method?

    • Bubble sort
    • Insertion sort
    • Linear search
    • Merge sort

12. Before writing code, an analyst determines the required user inputs and expected outputs. What phase is this?

    • Problem recognition
    • Unit testing
    • Code optimisation
    • Algorithm refinement

13. Representing a physical chess board state as a two-dimensional array in memory is an example of what?

    • Problem decomposition
    • Data abstraction
    • Procedural abstraction
    • Divide and conquer

14. Why does decomposition make large software development projects easier to manage for programming teams?

    • Increases execution speed
    • Eliminates syntax errors
    • Reduces memory usage
    • Enables parallel development

15. What are the three fundamental steps involved in a divide and conquer algorithm?

    • Divide, conquer, combine
    • Analyse, design, test
    • Input, process, output
    • Fetch, decode, execute

16. Which high-level computer science concept allows a programmer to use variables without managing hardware RAM addresses?

    • Decomposition
    • Pipelining
    • Abstraction
    • Branching

17. Why do divide and conquer algorithms typically rely on recursive programming techniques?

    • Loops cannot split
    • Uses less memory
    • Sub-problems match original
    • Avoids stack frames

18. What key activity occurs during problem recognition that must happen before problem decomposition can begin?

    • Writing pseudo-code
    • Defining the problem
    • Splitting into modules
    • Coding sub-routines

19. What risk arises if an abstract model removes too many details from a real-world system?

    • Infinite recursion
    • Stack overflow error
    • Inaccurate simulation
    • Increased time complexity

20. When does divide and conquer fail to improve performance compared to a simple iterative approach?

    • Halved problem size
    • Large input size
    • Overlapping sub-problems
    • Quick base case

Related quizzes

• Programming constructs, recursion and variable scope Quiz · 2.2.1a · 20 questions
• Modularity, parameter passing, IDEs and object-oriented techniques Quiz · 2.2.1b · 20 questions
• Backtracking, data mining, heuristics, performance modelling, pipelining, visualisation Quiz · 2.2.2b · 20 questions
• Processor components: ALU, control unit, registers and buses Quiz · 1.1.1a · 20 questions
• Operating systems and memory management Quiz · 1.2.1a · 20 questions
• Compression, encryption and hashing Quiz · 1.3.1 · 20 questions
• Primitive data types and binary number representation Quiz · 1.4.1a · 20 questions
• Data Protection Act 1998 and Computer Misuse Act 1990 Quiz · 1.5.1a · 20 questions
• The nature and need for abstraction and abstract models Quiz · 2.1.1 · 20 questions
• Algorithm design, suitability, efficiency and Big O notation Quiz · 2.3.1a · 20 questions