7.3 Programming 1

Question 1

What is an algorithm?

Answer 1

A set of instructions the computer follows in sequence.

Question 2

What is a sequence?

Answer 2

The order the program runs in.

Question 3

What is a variable?

Answer 3

A location in memory that stores one piece of data. It can change as the program runs.

Question 4

What is iteration?

Answer 4

When a block of code repeats/loops.

Question 5

What are the two iteration loops used in Python?

Answer 5

A for loop is count controlled, whereas a while loop is condition controlled.

Question 6

Why is iteration used in a program?

Answer 6

To make the program more efficient, e.g. less lines of code so the program runs faster.

Question 7

What does selection mean?

Answer 7

The user has a choice and the program has different routes to follow based on the choice.

Question 8

What are the key terms you would expect to see when reading a selection statement?

Answer 8

If/elif/else.

Question 9

What is the purpose of indentation?

Answer 9

The code belongs to the specific selection statement.

Question 10

Write a print statement.

Answer 10

print(‘A print statement’)

Question 11

Write an input statement for the user entering their name.

Answer 11

name = input(‘Enter your name: ’)

Question 12

How do the four types of malware get into the computer system?

Answer 12

Virus, worm, trojan and ransomware.

Virus - attaches; Worm - duplicates; Trojan - pretends; Ransomware - locks.

Question 13

What is a list?

Answer 13

A location in memory that stores multiple elements under one name.

Question 14

What is the difference between a variable and a list?

Answer 14

A variable can only store one element whereas a list stores multiple elements.

Question 15

How is a list defined in Python?

Answer 15

listName = [] (square brackets).

Question 16

What are the numbers in the binary number line?

Answer 16

128, 64, 32, 16, 8, 4, 2, 1.

Question 17

When converted to denary, the binary number 1001 is:

Answer 17

8 + 1 = 9.

Question 18

When converted to binary, the denary number 29 is:

Answer 18

29 - 16 = 13; 13 - 8 = 5; 5 - 4 = 1; 11101.

Question 19

Describe how an insertion sort is carried out.

Answer 19

An insertion sort is where the numbers are inserted into the correct position. It is the quickest kind of sorting.

Question 20

Describe how a merge sort is carried out.

Answer 20

A merge sort is where we divide and conquer - octo (8) - quads (4) - pairs (2) then sort pairs (2) - quads (4) - octo (8).

Question 21

Describe how a bubble sort is carried out.

Answer 21

In the bubble sort, you sort the pairs: 1st pass - start at 1st item; 2nd pass - start at 2nd item; 3rd pass - start at 1st item; 4th pass - start at 2nd item etc.

Question 22

Describe how a linear search is carried out.

Answer 22

A linear search is where each item in the list is checked until the correct item is found. This can be a slow process if the list is long.

Question 23

Describe how a binary search is carried out.

Answer 23

A binary search is where the list is divided in 2 - is the item you are looking for in the top half or bottom half - get rid of the half of the list it is not in, and repeat the process until you find the item you are looking for.