Linked Lists

A linked list is a linear data structure used to organize and store a collection of elements. Unlike arrays, linked lists do not have a fixed size and can dynamically grow or shrink as elements are added or removed. Linked lists consist of nodes, and each node contains two components: data and a reference (or link) to the next node in the sequence.


Components of a Linked List:

  1. Elements (Data): These are the individual data items stored in the linked list.
  2. Nodes: Nodes are the building blocks of a linked list. Each node contains the data element and a reference to the next node in the sequence.

Basic Operations on Linked Lists:

  • Insertion: This operation adds a new node with data to the linked list. It can be inserted at the beginning (head), end (tail), or at a specific position within the list.
  • Deletion: This operation removes a node from the linked list. It can involve removing the first node (head), last node (tail), or a node at a specific position.
  • Traversal: This operation involves traversing or iterating through the linked list to access, display, or manipulate the data in each node.
  • Search: This operation looks for a specific data element within the linked list and returns the node containing that data if found.

Types of Linked Lists:

  • Singly Linked List: In a singly linked list, each node points to the next node in the sequence, forming a unidirectional chain.
  • Doubly Linked List: In a doubly linked list, each node has references to both the next node and the previous node in the sequence, allowing bidirectional traversal.
  • Circular Linked List: In a circular linked list, the last node points back to the first node, creating a closed loop.

Common Use Cases:

  • Dynamic Data Structures: Linked lists are suitable for creating dynamic data structures where the size of the list can change during program execution.
  • Memory Management: Operating systems and programming languages often use linked lists for memory management tasks like tracking free memory blocks.
  • Implementing Other Data Structures: Linked lists are foundational in implementing other data structures such as stacks, queues, and hash tables.
  • Undo/Redo Functionality: Some software applications use linked lists to implement undo and redo functionality, allowing users to revert or redo actions.
  • Music and Playlist Management: Music playlist applications can use linked lists to manage playlists, allowing users to add, remove, and reorder songs.