2.1 Computational thinking

Question 1

computational thinking

Answer 1

the thought processes involved in understanding problems and formulating solutions in a way that they can be carried out by computers

Question 2

decomposition

Answer 2

reduces a problem into sub-problems or components, which are easier to understand and solve

Question 3

Show how decomposition can be used to break down the problem of creating a snakes and ladders computer game

Answer 3

sub-problems:

• design of playing area
• positions of snakes and ladders
• dice throw for each player
• movement of each player on board
• movement up ladders and down snakes
• how does a player finish?

Question 4

abstraction

Answer 4

identifying essential elements/relevant information and discarding inessential ones

Question 5

Name an essential and inessential element of a snakes and ladders game

Answer 5

generating a random number between 1 and 6 for a dice throw

how far the dice is thrown

Question 6

pattern recognition

Answer 6

sometimes called generalisation

used to:
-identify where constructs such as selection and iteration can be used

• identify where sections of code can be reused (functions and procedures)
• recognise a problem that is similar to one you have solved in the past
• reuse code, functions and procedures from past programs to carry out similar functions in a new program

Question 7

algorithmic thinking

Answer 7

a subset of computational thinking that involves defining a clear set of instructions to solve a problem

once a successful solution has been found, it can be used repeatedly for the same problem

Question 8

In a computer game ‘snakes and ladders’ there is a function named ‘dice throw’ which is called whenever it is a user’s turn.

Give a reason why this function is an abstractation [1]

Answer 8

it focuses on the essential purpose of throwing a dice and generating a number between 1 and 6

it ignores non-essential aspects like the colour of the dice

Question 9

Describe what is meant by the following terms:

a) decomposition
b) algorithmic thinking [4]

Answer 9

a) decomposition involves breaking a problem down into smaller, more manageable parts, which are then easier to solve

b) algorithmic thinking is one aspect of computational thinking
it is the ability to formulate a clear set of instructions to solve a problem

Question 10

advantages of decomposition

Answer 10

• makes complicated problems easier to solve
• individual parts of a problem allow multiple people to work on it at once
• components of a program can also be used in other programs