Abstract Data Types

ABSTRACT DATA TYPES (ADT)

• Abstract Data Types are models for data types
• They store collections of data
• They are accompanied by functions that perform operations on the data
• ADTs are created for use by programmers
• Programmers manipulate the collections of data
• ADTs are used to model collections of data in real world scenarios

COMPONENTS OF AN ADT

State

• Container of items itself
• Information about the container of items
• Includes size of the container
• Includes reference to the first item in the list

Operations

• Define how data in the ADT can be manipulated
• Examples include insertion, deletion, searching, and traversal
• Specify valid actions without showing how they are carried out

Implementation

• Actual coding structures that realize the ADT
• Examples include arrays, linked lists, or pointers
• Hidden from the user who only interacts with the abstract behaviour

DATA TYPES

• Describes the kind of data a variable can store
• Defines the operations that can be performed on that data (e.g. a char cannot be added to a number or multiplied by a number)

TYPES OF DATA TYPES

Primitive Data Types

• Basic, predefined types built into the programming language
• Directly supported by hardware
• Examples include int, float, char, double, boolean

Non-Primitive Data Types

• Derived from primitive data types
• Allow storage and manipulation of multiple values
• Examples include arrays, strings, structures, classes, pointers

DATA STRUCTURES

• Define how data is organized and stored for efficient access and modification
• Classified as linear or non-linear

Linear Data Structures

• Elements arranged sequentially
• Each element connected to its previous and next element
• Examples include Stacks, Queues, Linked Lists

Non-Linear Data Structures

• Elements connected hierarchically
• Allow multiple paths and relationships
• Examples include Trees, Graphs

TYPES OF ADTs

• Stacks
• Linked Lists (singly linked lists)
• Queues
• Circular Queues