Liquidated Data Structures

Question 1

Describe arrays.

Answer 1

A data structure for storing an ordered, finite set of elements of a single data type within a single identifier.
Always zero-indexed unless stated otherwise.

Question 2

What are 1D arrays considered to be?

Answer 2

Linear arrays

Question 3

2D ARRAYS
How can they be visualized?

Answer 3

As a table or spreadsheet.

Question 4

2D ARRAYS
How do you search across them?

Answer 4

When searching through them, go down the rows then across the columns to find a given position.

Question 5

3D ARRAYS
How can they be visualized?

Answer 5

3D arrays can be visualized as a multi-page spreadsheet, or as multiple 2D arrays

Question 6

3D ARRAYS
How do you search across them?

Answer 6

The three dimensions are used [z,y,x].
Z is the array number, y is the row number, x is the column number

Question 7

Describe records.

Answer 7

A data structure that stores data in a row of elements called fields, organised based on attributes.

Question 8

Describe lists.

Answer 8

A data structure that stores a sequence of data values, each with a unique index.

Question 9

How are lists different from arrays?

Answer 9

They can contain elements of more than one data type.

Question 10

Describe static and dynamic data structures

Answer 10

Static
• Structure size cannot change at runtime

Dynamic
• Structure size can change at runtime

Question 11

Describe mutable and immutable

Answer 11

Immutable
• Structure/data cannot be changed at runtime (overall cannot be modified)

Mutable
• Structure/data can be changed at runtime

Question 12

Describe stacks.

Answer 12

A Last in First out (LIFO) data structure.
Items can only be pushed (added) or popped (removed) from the top.
The top is identified with a top pointer.
It is preferably static. (easier to implement, more efficient memory use)

Question 13

Describe linear queues.

Answer 13

First in First out (FIFO) data structure
Items are added to the end (enqueue) and removed at the front (dequeue).
Has a front pointer and a rear pointer.

Question 14

Describe circular queues

Answer 14

First in First out (FIFO) data structure
Once the queue’s rear pointer is equal to the max size of the queue, it can loop back to the front of the array and store values here, provided it is empty.
Harder to implement, but uses space in an array more effectively.

Question 15

Define tuple

Answer 15

A data structure for storing an immutable, ordered set of data, which can be of different data types within a single identifier.

Question 16

What is different about the way tuples are initialized?

Answer 16

Regular brackets are used instead of square

Question 17

What is different about the way arrays and tuples are accessed?

Answer 17

Nothing. They can be accessed the same way (with the exception of changing the value).

Question 18

Define linked list.

Answer 18

Dynamic data structure used to hold an ordered sequence. Each item is called a node, and contains a data field and a pointer which points to the next item in the list.