7.2 Computational Methods (OCR A Level Computer Science): Exam Questions

48 mins12 questions
11 mark

Fig. 5 shows a graph data structure representing a small section of a parcel delivery network. Each node represents an address where deliveries need to be made. The edges show the possible routes and distances between these deliveries.

Graph with nodes labelled A to H connected by edges with weights 3, 7, and 11. Key connections: D-H (11), B-E (3), D-C (3), E-F (3).

State why performance modelling is used to test a system.

Did this page help you?

23 marks

A Nonogram is a logic puzzle where a player needs to colour in boxes. The puzzle is laid out as a grid and each square needs to be either coloured black or left white.

The numbers at the side of each row and column tells the player how many of the boxes are coloured in consecutively. Where a row has two or more numbers, there must be a white square between the coloured squares.

A 5x5 nonogram puzzle grid with black and white squares. Numbers on the right and bottom indicate sequences of contiguous black squares.

In this example:

  • the first column has 1 1, this means there must be two single coloured boxes in this column. There must be at least 1 white box between them.

  • the first row has 2, this means there must be two consecutively coloured boxes in the row.

Juan is creating a program that will store a series of Nonograms for a user to play. The game will randomly select a puzzle and display the blank grid with the numbers for each row and column to the user

The user plays the game by selecting a box to change its colour. If the box is white it will change to black and if it is black it will change to white. The user can choose to check the answer at any point, and the game will compare the grid to the answers and tell the user if they have got it correct or not.

Juan is creating a structure diagram to design the game.

Complete the structure diagram by adding another layer for New game, Play game and Check answer.

Flowchart showing "Nonogram" at the top, branching into "New game," "Play game," and "Check answer" with empty boxes below each.

Did this page help you?

32 marks

Define the term "problem decomposition" and state its purpose in computational methods.

Did this page help you?

42 marks

State what is meant by "heuristics" in problem solving, and why are they used.

Did this page help you?

12 marks

Explain why decomposing a problem can help a developer design a solution.

Did this page help you?

22 marks

Fig. 5 shows a graph data structure representing a small section of a parcel delivery network. Each node represents an address where deliveries need to be made. The edges show the possible routes and distances between these deliveries.

Graph with nodes A-H connected by edges. Edge weights: A-B 3, B-D 7, D-H 11, H-G 3, G-F 7, F-E 3, E-C 7, C-D 3, B-E 3.
Fig. 5

Describe how performance modelling can be used in the delivery system.

Did this page help you?

33 marks

A card game uses a set of 52 standard playing cards. There are four suits; hearts, diamonds, clubs and spades. Each suit has a card with a number from; 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13.

The card game randomly gives 2 players 7 cards each. The unallocated cards become known as the deck.

The players then take it in turns to turn over a card. A valid move is a card of the same suit or the same number as the last card played.

The winner is the first player to play all of their cards.

One component of the game is checking if a move is valid.

Identify three other components of the game.

Did this page help you?

42 marks

Taylor is going to use graphs to plan the movements that each character can take within a game.

Characters in the game will move and interact independently.

DancerGold is one character. The graph shown in Fig. 1 shows the possible movements that DancerGold can make.

Graph diagram with seven nodes labelled A to G, connected by weighted edges. Each node has a number indicating its value. Caption reads "Fig. 1".

DancerGold’s starting state is represented by node A.

DancerGold can take any of the paths to reach the end state represented by node G.

The number on each path represents the number of seconds each movement takes.

The number in bold below each node is the heuristic value from A.

Define the term heuristic in relation to the A* algorithm.

Did this page help you?

54 marks

Amy’s processor makes use of pipelining during the fetch-decode-execute cycle

The processor’s pipeline consists of the following stages:

  • Fetching the instruction from memory

  • Decoding the instruction

  • Executing the instruction.

Instructions A, B, C and D need to be processed.

Identify the stage(s) and instruction(s) run during each pipeline below..

Stage(s)

Instruction

Did this page help you?

19 marks

A company needs a new computer program that will create schedules for delivery drivers. It will need to identify a possible order that the drivers can deliver items and possible routes they could take.

Discuss how programmers could make use of problem recognition and problem decomposition when designing this system.

You should include the following in your answer:

  • a description of both problem recognition and decomposition

  • how each method can be used when designing the solution

  • the benefits of using each method when designing the solution.

Did this page help you?

29 marks

Taylor is creating an online multiplayer game where users can create accounts and build their own circus. Each circus will contain characters such as clowns, animals, magicians and dancers.

Users can set up a new circus in the online world, purchase new characters and visit other users’ circuses.

The game will have thousands of users. Taylor will store data about the users and their actions while playing the game in a large database.

Evaluate how Taylor can use data mining to inform future changes to improve his circus game.

Did this page help you?

39 marks

Evaluate the importance of performance modelling in software development. Use examples to discuss its benefits and limitations.

Did this page help you?