8525 Unit 1

Question 1

Algorithm definition

Answer 1

An algorithm is a set of instructions for solving a problem or completing a task

Question 2

Abstraction definition

Answer 2

Involves removing unnecessary detail from a problem so that you can focus on the essential components

E.g. London Underground

Question 3

Decomposition definition

Answer 3

Involves breaking down a large problem into smaller sub-problems

Question 4

Decomposition advantages

Answer 4

Problem becomes easier to solve
Some modules may be reusable in other programs, saving development time
Can collaborate

Question 5

Computational thinking

Answer 5

The use of computers to solve problems

Question 6

Start/end flowchart symbol

Answer 6

Rounded rectangle looking thing
__________
(__________)

Question 7

Input/output flowchart symbol

Answer 7

Parallelogram

Question 8

Sub-process flowchart symbol

Answer 8

_____________
|__|_____|__|

Rectangle with two lines in the middle

Question 9

Process flowchart symbol

Answer 9

Rectangle

Question 10

Decision flowchart symbol

Answer 10

Rhombus with one arrow coming out on the right and one arrow going down
Labelled true/yes and false/no

Question 11

What is a flowchart

Answer 11

A diagram that shows the inputs, outputs and processes in an algorithm

Question 12

All programs are composed of three basic structures:

Answer 12

Sequence
Selection
Iteration

Question 13

What is a sequence

Answer 13

A series of steps which are completed one after another

Question 14

What is selection

Answer 14

Selection is the ability to choose difference paths through a program

Question 15

What is iteration

Answer 15

Means repeating a part of a program
Referred to as repetition or looping

Question 16

Data types

Answer 16

Integer—whole number—1475,0,-5

Real—number with a decimal point—56.75, 6.0, -2.5, 0.0

Character—a single alphabetic/numeric/symbol character

String—one or more characters enclosed in quote marks

Question 17

Iteration statements

Answer 17

FOR…ENDFOR

WHILE…ENDWHILE

REPEAT…UNTIL

Question 18

Write a search algorithm for numbers <- [5,1,9,8,7,6,4,10]
In linear search

Answer 18

numbers <- [5,1,9,8,7,6,4,10]
searchItem <- STRING_TO_INT(USERINPUT)
FOR i <- 0 TO LEN(numbers) - 1
IF numbers[i] = searchItem THEN
OUTPUT “searchItem found”
ENDIF
ENDFOR