Understanding Linked Lists
Linked lists consist of:
- Nodes: Each node contains data and a pointer to the next node.
- Head: Pointer to the first node in the list.
- Tail: The last node, which points to null.
Logical vs physical representation of linked lists:
- Logical Representation: How the list is viewed conceptually (nodes and pointers).
- Physical Representation: How the list is stored in memory (addresses and data types).
This distinction is an example of abstraction, hiding complex details to focus on essential features.
- Advantages of linked lists include:
- Dynamic Size: Can grow or shrink as needed.
- Efficient Insertions/Deletions: No need to shift elements, unlike arrays.
- Disadvantages of linked lists:
- Sequential Access: Must traverse the list to access elements.
- Memory Overhead: Each node requires extra memory for pointers.
Stacks, queues, and graphs can be built using linked lists.
Types of Linked Lists
Singly linked list: Each node points to the next node.
Example
Doubly linked list: Each node points to both the next and previous nodes.
Example
Doubly linked lists are ideal for applications that require frequent bidirectional traversal, such as navigation systems.
Circular linked list: The last node points back to the first node, forming a loop.
Example
Circular linked lists are often used in operating systems for task scheduling, where each task is processed in a continuous loop.
Key Operations on Linked Lists
We can work with linked lists via:
- Insertion: Adding a new node.
