Linked Lists in Data Structures
A linked list is a linear data structure where elements are stored in nodes. Each node contains data and a pointer to the next node. Unlike arrays, linked lists allow dynamic memory allocation and efficient insertion and deletion.
What is a Linked List?
A linked list consists of nodes, where each node contains:
- Data – The actual information
- Next pointer – Points to the next node in the list
Key Characteristics:
- Dynamic size
- Non-contiguous memory allocation
- Sequential access via pointers
Types of Linked Lists
1. Singly Linked List
- Each node points to the next node
- Last node points to
NULL
2. Doubly Linked List
- Each node has two pointers: next and previous
- Supports traversal in both directions
3. Circular Linked List
- Last node points back to the first node
- Can be singly or doubly circular
Basic Operations on Linked Lists
1. Traversal
Visit each node from head to end.
2. Insertion
Add a node at:
- Beginning
- End
- Specific position
3. Deletion
Remove a node from:
- Beginning
- End
- Specific position
4. Searching
Find a node with specific data.
5. Updating
Modify the data of a node.
Advantages of Linked Lists
- Dynamic memory allocation
- Efficient insertion and deletion
- No memory wastage
- Flexible structure
Disadvantages of Linked Lists
- Sequential access only (no random access)
- Extra memory for pointers
- Complex implementation compared to arrays
Real-World Applications of Linked Lists
- Dynamic memory management
- Implementation of stacks and queues
- Music or video playlists
- Undo/Redo operations in software
- Graph and tree representations
Linked List vs Array
| Linked List | Array |
|---|---|
| Dynamic size | Fixed size |
| Non-contiguous memory | Contiguous memory |
| Easy insertion/deletion | Costly insertion/deletion |
| Extra memory for pointers | No extra memory |
Conclusion
Linked lists are a flexible and dynamic data structure used for efficient memory management and insertion/deletion operations. Mastering linked lists is crucial for understanding advanced data structures like stacks, queues, trees, and graphs.