Structured and object oriented programming

 

Abstract data type

• A useful tool for specifying the logical properties of a data type is the abstract data type or ADT.

• Fundamentally, a data type is a collection of values and set of operation on those values.

• That collection and those operations form a mathematical construct that may be implemented using a particular hardware or software data structure.

• The term “Abstract Data type” refers to the basic mathematical concept that defines the data type.

• Formally, An abstract data type is a data declaration packaged together with the operations that are meaningful on the data type.

• In other words, we can encapsulate the data and the operation on data and we hide them from user.

• It is a mathematical model that contains set of values and function on thoses values without specifying the details of those functions.

Examples of ADT :

1. Linear ADTs:

Stack (last-in, first-out) ADT

Queue (first-in, first-out) ADT

a. Lists ADTs

Arrays

Linked List

Circular List

Doubly Linked List

2. Non-Linear ADTs

a. Trees

Binary Search Tree ADT

b. Heaps

c. Graphs

Undirected

Directed

d. Hash Tables

We can perform following basic operations on ADTs insert(),delete(), search(), findMin(),findMax(),findNext(), findPrevious(), enqueue(), dequeue() etc.