T6 - Flowcharts/Pseudo-code

Question 1

Variable

Answer 1

• location in memory in which you can temporarily store a value such as a string
  or number

Question 2

Algorithm

Answer 2

• series of steps to solve a problem or carry out a task

Question 3

Sub programs

Answer 3

• used when you wish to call another procedure or function

Question 4

three programming constructs used to control the flow of a program:

Answer 4

Sequence
Selection
Iteration (repetition)

Question 5

Sequence:

Answer 5

A sequence is a series of steps which are completed one after the other

statements are executed one by one, in the order they are written

Question 6

Selection:

Answer 6

is the ability to choose different paths through a program
In flowcharts, decision symbols are used for selection

Question 7

Iteration:

Answer 7

means repeating a part of a program
- repeating or looping

Question 8

eg of iteration

Answer 8

for … next
while … endwhile
do … until (doesn’t exist in python)

Question 9

Boolean operators:

Answer 9

>

greater than =	greater than or equal to <	less than <=	less than or equal to ==	equal to !=	not equal to

Question 10

integer

Answer 10

whole number

Question 11

real

Answer 11

number with a decimal point

Question 12

boolean

Answer 12

true or false value

Question 13

character

Answer 13

single alphabetic / numeric character

Question 14

string

Answer 14

sequence of one or more characters

Question 15

Pseudocode:

Answer 15

kind of structured English for describing algorithms
allows a programmer to focus on the logic of the algorithm without being distracted by the exact syntax of the programming language

Question 16

Selection:

Answer 16

An IF statement is a type of selection statement
The next statement to be executed depends on whether the condition being tested is TRUE or FALSE

Question 17

The switch/case statement

Answer 17

• used if there are several possible options to be tested

Question 18

Do… until loop:

Answer 18

Use this when you want to keep on executing a loop until a certain condition is TRUE
The condition is tested at the end of the loop

Question 19

How to find mistakes in programmes:

Answer 19

trace tables

Question 20

Use a trace table:

Answer 20

programmer goes through the code, line by line, writing down the values of variables

Question 21

Trace tables:

Answer 21

determine the outputs from a program as it runs
enable a programmer to find errors in their programs

Question 22

Advantages of trace tables:

Answer 22

Determining the purpose of an algorithm
Finding the output of an algorithm
Finding errors in an algorithm

Question 23

Drawing trace tables:

Answer 23

make a column for each variable used, in the order in which they appear
You don’t need to fill in a value for a variable which does not change in a particular row
A row is used for each iteration

Question 24

Logical error -

Answer 24

when programmes work but gives a result that wasn’t intended by the programmer.
the logic of the program is incorrect

Question 25

Syntax error

Answer 25

• programme won’t work
  doesn’t follow the rules of the language

Question 26

Sequence in flow chart

Answer 26

In a flow diagram they are shown as process, input or output symbols shown one after the other

Question 27

Iteration in flow charts

Answer 27

In flowcharts, iteration = arrows that repeat a section of the flowchart
A decision will control whether more iterations are required