OCR Computer Science AS Level - 1.4.2 Data Structures

Vocabulary flashcards for OCR Computer Science AS Level 1.4.2 Data Structures

Array

An ordered, finite set of elements of a single type.

Linear Array

A one dimensional array.

Two Dimensional Array

You can visualise it as a spreadsheet/table.

Three Dimensional Array

A three dimensional array can be visualised as a multi-page spreadsheet.

Record

A row in a file

Record

A record is made up of fields.

Identifying a field from a record using programming

recordName.fieldName

List

A data structure consisting of a number of items, where the items can occur more than once.

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.

Tuple

An immutable, ordered set of values of any type.

Difference between a tuple and an array

Tuples are initialised using regular brackets instead of square brackets.

Stack

A last in first out data structure, where items can only be removed from and added to the top of the list

Example of where stacks may be used

• Back button in a web page - Undo buttons

Queue

A first in first out data structure, where items are added to the end of the queue and removed from the front of the queue.

isEmpty() operation (Stacks)

Checks to see if the stack is empty

push(value) operation (Stacks)

Adds a new value to the top of the stack

peek() operation (Stacks)

Returns the top value of the stack without removing it

pop() operation (Stacks)

Returns and removes the value at the top of the stack

size() operation (Stacks)

It returns the size of the stack

isFull() operation (Stacks)

Checks to see if the stack is full.

enQueue(value) operation (Queues)

Adds the value to the end of the queue

deQueue() operation (Queues)

Removes the item from the end of the queue

isEmpty() operation (Queues)

It checks to see if the queue is empty

isFull() operation (Queues)

Checks to see if the queue is full