Computer Science GCSE Unit 2

What is an algorithm?

• A flowchart

• Step by step instructions used to solve a problem

• A decision

• A flowchart or pseudocode

What are the three algorithm constructs?

• Sequence, Selection, Iteration

• Input, Process, Output

• Input/output, decision, terminator

• Loop, input/output, process

What is the difference between a flowchart and pseudocode?

• A flowchart is diagrammatic whilst pseudocode is written in a programming language

• A flowchart is textual but pseudocode is diagrammatic

• A flowchart is a diagrammatic description of an algorithm whilst pseudocode is a textual description of an algorithm

• A flowchart and pseudocode are the same thing

In a flowchart an input or output instruction is represented by:

• A rectangle

• A rhombus

• A parallelogram

• A circle

In a flowchart a calculation (process) is represented by:

• A rectangle

• A rhombus

• A parallelogram

• A circle

An algorithm asks a user to enter their age, the age is read into the system and the system outputs a 'Thank You' message.

This is an example of which of the algorithm construct?

• Decision (Selection)

• Loop (Iteration)

• Order (Sequence)

• All of the above

An Algorithm asks the user to enter their scores for 5 different tests.

This is an example of which of the algorithm constructs?

• Decision (Selection)

• Loop (Iteration)

• Order (Sequence)

• All of the above

An Algorithm asks the user to enter their gender (M or F) and prints out a different comment depending on what they entered.

This is an example of which of the algorithm constructs?

• Decision (Selection)

• Loop (Iteration)

• Order (Sequence)

• All of the above

What is a "Variable" ?

• A value that can be changed and manipulated as an algorithm is running

• A value that cannot be changed and manipulated as an algorithm is running

Variables are assigned an identifier. The identifier should be:

• not too long

• have a sensible name

• not start with a number

• not start with a capital letter

• all of the above