1.4.2 Data Structures Flashcards
What is an array?
An ordered, finite set of elements of a single type.
What type of array is a linear array?
A one dimensional array
How can you visualise a two dimensional array?
You can visualise it as a spreadsheet/table
How can you visualise a three dimensional array?
A three dimensional array can be visualised as a multi-page spreadsheet
What is a record also known as?
A row in a file
What is a record made up of?
A record is made up of fields.
How can you select a field from a record using pseudocode?
recordName.fieldName
What is the definition of a list?
A data structure consisting of a number of items, where the items can occur more than once
What are the main differences between arrays and lists?
- Lists can store data non-contiguously
whereas arrays store data in order. - Lists can store data of more than one
data type
What is a tuple?
An immutable, ordered set of values of any type
What is the difference between a tuple and an array?
Tuples are initialised using regular brackets instead of square brackets
What is a stack?
A last in first out data structure, where items can only be removed from and added to the top of the list
Give an example of where stacks may be used.
- Back button in a web page
- Undo buttons
What is a queue?
A first in first out data structure, where items are added to the end of the queue and removed from the front queue.
What does the operation isEmpty() do?
Checks to see if the stack is empty
What does the operation push(value) do?
Adds a new value to the top of the stack
What does the operation peek() do?
Returns the top value of the stack without removing it
What does the operation pop() do?
Returns and removes the value at the top of the stack
What does the operation size() do?
It returns the size of the stack
What does the operation isFull() do?
Checks to see if the stack is full
What does the operation enQueue(value) do?
Adds the value to the end of the queue
What does the operation deQueue() do?
Removes the items from the end of the queue
What does the operation isEmpty() do?
It checks to see if the queue is empty
What does the operation isFull() do?
Checks to see the queue is full
