Discuss various classifications of data structures with an example.

Classifications of Data Structures

Data structures are classified into two main categories:

Linear Data Structures:

• Arrays: An array is a collection of elements of the same type stored in contiguous memory locations. They are efficient for accessing and manipulating elements in a sequential manner.

• Linked Lists: A linked list is a collection of nodes, where each node contains a data item and a reference (or link) to the next node in the list. Linked lists are useful for representing data that is not stored contiguously in memory.

• Stacks: A stack is a linear data structure that follows the Last-In-First-Out (LIFO) principle. This means that the last element added to the stack is the first one to be removed. Stacks are implemented using arrays or linked lists.

• Queues: A queue is a linear data structure that follows the First-In-First-Out (FIFO) principle. This means that the first element added to the queue is the first one to be removed. Queues are implemented using arrays or linked lists.

Non-Linear Data Structures:

• Trees: A tree is a hierarchical data structure that consists of nodes connected by edges. Each node can have multiple child nodes, but only one parent node. Trees are used to represent hierarchical data, such as file systems and organizational charts.

• Graphs: A graph is a non-linear data structure that consists of vertices (or nodes) and edges. Unlike trees, graphs can have cycles, meaning that there can be a path from one vertex back to itself. Graphs are used to represent complex relationships between objects, such as social networks and transportation networks.

• Hash Tables: A hash table is a data structure that uses a hash function to map keys to values. Hash tables are efficient for searching and retrieving data based on a key, making them useful for implementing associative arrays and dictionaries.

Example:

Consider a simple inventory management system that keeps track of products and their quantities. We can use the following data structures to represent the inventory:

• Product: Each product can be represented by a record containing its name, description, price, and quantity. We can store all products in an array or a linked list.

• Inventory: The inventory can be represented by a hash table where the keys are product names and the values are product quantities. This allows us to quickly look up the quantity of a specific product.

• Shopping Cart: A shopping cart can be represented by a linked list or an array of products. This allows us to add and remove products from the cart and calculate the total price of the items.

Conclusion:

Data structures are essential for organizing and managing data in computer programs. The choice of data structure depends on the specific requirements of the application. Linear data structures are suitable for representing sequential data, while non-linear data structures are useful for representing hierarchical or complex relationships between objects.