2017

Question 1

Max comparisons in a binary search

Answer 1

Finding power of two greater than items in the list

Eg List size 5 2^3=8 so 3 is answer

Question 2

No of comparisons in a linear search

Answer 2

N/2 (n is number of items in the list)

Question 3

Linear Search facts

Answer 3

Simple algorithm
List may be unsorted
Number of comparisons given by n/2
Slow for large lists

Question 4

Binary Search facts

Answer 4

Complex algorithm
List must be sorted
Max comparisons given by power of two greater than items in list eg 5 items would be 2^3=8 so 3 is answer
Fast for large lists

Question 5

Why selection sort two lists is inefficient

Answer 5

Has to check every item from list every time loop executes

Requires second list with same storage space as first= problem if large list being sorted

Question 6

Comparing Binary and Linear Search

Answer 6

Binary search requires list to be sorted - more complex so more processor time
Linear search more efficient on smaller lists

Question 7

Bubble sort facts

Answer 7

No additional operation memory as swaps items between positions in a list
Faster for a partially sorted list as variable can be introduced to keep track of whether swaps have occurred or not
Unconditional version will make n passes through list and n^2 comparisons
In worst case scenario - reverse order = n^2 swaps also
Number of swaps depends on how partially sorted original list is

Question 8

Insertion Sort number of passes

Answer 8

Always n-1 where n is the number of items in the list
Outer loop goes from 1 up to number of elements
(Missing element zero)

Question 9

Quick Sort facts

Answer 9

Recursive algorithm - Suitable for parallel processing
Memory intensive
Inefficient for sorting lists which contain lots of similar terms

Question 10

Merge Sort

Answer 10

Divides into sorted sub lists and puts two sorted lists together to make one large sorted list
Useful if you have two sorted lists which have to be put together

Question 11

Divide and Rule Algorithms

Answer 11

Merge sort

Quick sort

Question 12

Explain why a class may have position variables and others do not

Answer 12

The parent class will have properties which are inherited

Question 13

Explaining encapsulation in terms of certain class

Answer 13

Object properties would be hidden and inaccessible outside the specified class or subclass

Code within classes methods may manipulate properties of an instance of that class ie the position coordinates of that instance

Question 14

Why classes may be inefficiently structured

Answer 14

Repetition of many lines of code ie methods and properties in multiple subclasses

Question 15

How classes can be made more efficient

Answer 15

Create a subclass and place all common properties/methods in here
Create two new subclasses of this subclass with only their unique property

Question 16

Explain using object-oriented terminology how you would get Mario to change to a penguin costume

Answer 16

The change_costume method of Mario is called

Question 17

Explain how a company could use goal tracking in order to evaluate development success

Answer 17

Set sales goal
Analysis of sales figures would indicate whether it had been achieved or not
Development success determined by whether goal was met or not

Question 18

How a company can protect its interests when getting rights for work

Answer 18

Ensure it owns/ has defined use of any intellectual property rights related to artists work

Question 19

Explain how tracking information could be used by a company to influence future development

Answer 19

• Cookies gather data about players’ profiles, games they play. Frequency of visit.
• Analysis of this data will show which games are popular with certain age groups.
• Business can focus on areas likely to generate income.

Question 20

Difference between GET and POST methods

Answer 20

GET is used when search criteria is displayed in browser address bar
POST is used when search criteria is not

Question 21

The value in a HTML form

Answer 21

The text displayed inside the search box eg search or enter catalogue number

Question 22

The name in a HTML form

Answer 22

Eg criteria for where you enter criteria or search box for where you enter search credentials

Question 23

Describe how testing of a customer order process is integrative

Answer 23

Customer order process requires a server side script to activate the SQL instruction
used to extract the required details from the database
Two separate technologies in use means integrative testing is required to ensure that they connect and communicate correctly

Question 24

Types of maintenance

Answer 24

Perfective - Carried out on an existing system to improve it
Corrective - Carried out to fix any errors which should not be contained within
Adaptive - Used when client requires software to run on environment different to the one it was built for

Question 25

Explain two ways analytics could be used to inform an online marketing campaign

Answer 25

Evaluating visitor stats from the company’s own sites/Social media sites
This enhances search engine rankings
Allows for most effective product placement points and links

• Using social media analytics to
  Determine the most productive links to groups
  Evaluate advertising placement success
  Assess prior success of competitions/launches

Question 26

Data required to implement a stack

Answer 26

1D Array
Stack Pointer/Integer variable which is used to store
the index/position of the current top value of the stack
and
Next available space

Question 27

Explain why an execution error can occur when adding an item to a stack using a 1D Array

Answer 27

Stack is full or stack overflow

An array is of a fixed size - An attempt to exceed this gives an out of range error

Question 28

Explain why an execution error would not occur on a linked list as it would on a stack

Answer 28

Linked lists do not have fixed size - They are a dynamic data structure
Items are not stored contiguously in memory, making it easier to add new items

Question 29

Explain why a bubble sort will make another pass through the list, even though it is sorted

Answer 29

A swap has taken place and so the Boolean variable will still be set to true
Terminating condition of having no swaps will not have been met until the end of the second pass

Question 30

State an error which may have occurred when swapping data

Answer 30

Name in the wrong position when scores are swapped because algorithm does not swap names also