CT and Programming

Question 1

What is the shape for a

start or end of the program

in a flowchart?

Answer 1

an oval

Question 2

What is the shape for a

process

in a flowchart?

Answer 2

a rectangle

Question 3

What is the shape for a

decision

in a flowchart?

Answer 3

a diamond

Question 4

What is the shape for an

input or output

in a flowchart?

Answer 4

a parallelogram

Question 5

What is the shape for a

subprogram

in a flowchart?

Answer 5

a rectangle with two rectangles either side

Question 6

What is a

constant?

Answer 6

a memory location that holds a value that does not change when the program is run

Question 7

Define

sequencing.

Answer 7

completing instructions in order, one after another

Question 8

Define

selection.

Answer 8

choosing a path of instructions to follow based on a Boolean condition

Question 9

What is

decomposition?

Answer 9

usually the first step in the problem-solving process, where the problem is broken down into smaller, more manageable parts which are then easier to solve

Question 10

What are the positives of

decomposition?

(and subprograms in general) (3)

Answer 10

• sub-problems can be worked on by different teams at the same time
• it is easier to spot and correct errors
• code can be reused

Question 11

What is

abstraction?

Answer 11

the removal of unecessary detail in a problem

Question 12

Define

data structure.

Answer 12

an organised collection of related elements

Question 13

What does an

array do?

and give an example.

Answer 13

store data items all of the same data type

e.g.
[“Alice”, “Barry”, “Catherine”]
[75, 82, 45, 55]

Question 14

What does a

record do?

and give an example.

Answer 14

stores a set of related elements of different data types

e.g.
[384, “Collins”, “Ivy”, 2010, 15.34]

Question 15

What is a

field?

Answer 15

each element in a record

Question 16

What are the

similarities and differences of iteration and repetition?

(1 of each)

Answer 16

+iteration and repetition both repeat a section of an algorithm
-iteration repeats for every item in a data structure whereas repetition repeats either a fixed number of time, or until a condition is met

Question 17

What are some examples of

input validation?

(4)

Answer 17

• range check
• length check
• presence check
• pattern check

Question 18

What are the

three broad categories of errors?

Answer 18

• syntax errors
• run-time errors
• logic errors

Question 19

What is a

syntax error?

and what are some examples?

Answer 19

an error that breaks the rules of the grammar of the language

e.g. misspelled keywords, missing or excessive indentation

the computer cannot translate the code into machine code, and so cannot run it

Question 20

What is a

run-time error?

and what are some examples?

Answer 20

an error that causes a program to crash because it cannot execute one of the instructions in the code

e.g. divide by zero, index out of range

Question 21

What is a

logic error?

and what are some examples?

Answer 21

an error that causes incorrect or unwanted behaviours

e.g. wrong arithmetic operator or mixing up two variable names