Algorithms

Question 1

What is an algorithm?

Answer 1

A sequence of logical instructions for carrying out a task.

Question 2

What are two common methods for designing algorithms?

Answer 2

Pseudo-code and flowcharts.

Question 3

What do algorithms focus on when being designed?

Answer 3

The logic of the steps.

Question 4

What is meant by ‘language independent’ in the context of algorithms?

Answer 4

Programmers should be able to translate an algorithm into any programming language.

Question 5

Fill in the blank: An algorithm can be designed using _______ and/or flowcharts.

Answer 5

pseudo-code

Question 6

True or False: Algorithms are specific to a programming language.

Answer 6

False

Question 7

What is the purpose of using statements and expressions in algorithms?

Answer 7

To provide clear instructions for solving a problem.

Question 8

What is pseudo-code?

Answer 8

A method of writing up a set of instructions for a computer program using plain English.

Question 9

What is a flowchart?

Answer 9

A diagram that shows the step-by-step flow of an algorithm.

Question 10

What is a statement in an algorithm?

Answer 10

The smallest element of a programming language which expresses an action to be carried out.

Question 11

What is a programming language?

Answer 11

A language used by a programmer to write a piece of software.

Question 12

What is decomposition?

Answer 12

Breaking down a complex problem or system into smaller parts that are more manageable and easier to understand.

Question 13

What is abstraction?

Answer 13

The process of extracting or withdrawing something eg. The underground Map

Question 14

Psuedo-code can be broken into three sections. What are they?

Answer 14

Inputs
Processes
Outputs

Question 15

What is assignment?

Answer 15

Setting the value of a variable in a computer program.

Question 16

What is a variable?

Answer 16

A memory location within a computer program where values are stored.

Question 17

What are data?

Answer 17

Units of information. In computing there can be different data types, including integers, characters and Boolean.

Question 18

What symbols should be used for pseudo-code?
Line

Answer 18

It represents the flow from one component to the next.
An arrow.

Question 19

What symbols should be used for pseudo-code?
Process

Answer 19

An action.
A rectangle.

Question 20

What symbols should be used for pseudo-code?
Subroutine

Answer 20

Calls a subroutine,
A rectangle.

Question 21

What symbols should be used for pseudo-code?
Input / Output

Answer 21

Calls an input or an output.

A squashed rectangle.

Question 22

What symbols should be used for pseudo-code?
Decision

Answer 22

A yes/no/true/false decision.
A kite shape.

Question 23

What symbols should be used for pseudo-code?
Terminator

Answer 23

The start or end of the process,
A rounded rectangle.

Question 24

What is an input?
eg. in pseudo-code
myVar <– Input

Answer 24

Data which is inserted into a system for processing and/or storage as a variable.

Question 25

What is an output?

Answer 25

Data which is sent out of a system and shown to the user.

Question 26

How does a program communicate with the user?

Answer 26

The user must input data into the system This data must be processed The outcome is output to the user The data is stored for later use

Question 27

What does a dry run mean?

Answer 27

Dry running an algorithm means to assign the values to variables of an algorithm and to do any processing that takes place without translating it into code.

Question 28

What is a trace table?

Answer 28

Used when testing a program to record changes in variable values as code executes.

Question 29

What is a standard algorithm?

Answer 29

A commonly agreed programming solution to a specific problem.

Question 30

What does bubble sort mean?

Answer 30

A sorting algorithm that repeatedly passes through a list to be sorted, comparing and swapping items that are in the wrong order.

Question 31

What does merge sort mean?

Answer 31

A sorting algorithm that repeatedly divides a list in half until each has only one item. The individual lists are then merged.

Question 32

What does efficiency look at?

Answer 32

Efficiency looks at how much time it takes to run a particular algorithm and how much space is needed.

Question 33

What is an array?

Answer 33

A set of data values of the same type, stored in a sequence in a computer program. Also known as a list.