2: introduction to data structures

A data type consists of
? a domain (= a set of values)
? A set of operations.
Example 1: Boolean or logical data type provided by most programming languages.
? Two values: true, false.
? Many operations, including: AND, OR, NOT, etc.
Abstract Data Type (ADT):
The basic idea behind an abstract data type is the separation of the use of the data type from its implementation (i.e., what an abstract data type does can be specified separately from how it is done through its implementation)
The advantages of using the ADT approach are:
1. The implementation of ADT can change without affecting those method that use the ADT
2. The complexity of the implementation are hidden
For example, an abstract stack data structure could be defined by two operations: push, that inserts some data item into the structure, and pop, that extracts an item from it.
Advantages of data structures
The major advantages of data structures are: • It gives different level of organizing data. • It tells how data can be stored and accessed in its elementary level
Operation on Data Structures
The operations that can be performed on data structures are: Creation: This operation creates a data structure. The declaration statement causes space to be created for data upon entering at execution time.
Destroy: This operation destroys the data structure and aids in the efficient use of memory.
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Selection: This operation is used to access data within a data structure. The form of selection depends on the type of data structure being accessed.
Update: This operation changes or modifies the data in the data structure and it is an important property in selection operation.
Types of Data Structures
Linear Data Structure: Stacks, Queues, Linked Lists, etc.
Non-linear Data Structure: Trees, Graphs, etc .
As illustrated generally in the below block diagram.