Lecture 169:-  More About Linked List

 

Certainly! Let's dive deeper into some important concepts and operations related to linked lists.
 

1. Node Structure: A node in a linked list typically contains two parts: a data field (or payload) to store the value of the element and a reference (or pointer) to the next node in the sequence. For a doubly linked list, each node also has a reference to the previous node.

cppCopy code

struct Node {    int data;     // Data or payload of the node    Node* next;   // Pointer to the next node in the sequence    // For a doubly linked list:    // Node* prev; // Pointer to the previous node };

1. Creating a Linked List: A linked list is created by allocating memory for nodes and properly linking them together. The first node is often referred to as the "head," and the last node is the "tail."
2. Linked List Traversal: Traversing a linked list means visiting each node in the list in a specific order (e.g., from head to tail). Traversal is commonly performed using a loop or recursive function, starting from the head and moving to the next node until reaching the end (i.e., when the next pointer is NULL).
3. Insertion in Linked List: Insertion in a linked list can be performed at various positions, such as at the beginning (front), at the end (back), or in the middle. To insert a new node, you need to update the appropriate pointers to maintain the linkage between nodes.
4. Deletion in Linked List: Deleting a node in a linked list involves adjusting the pointers of neighboring nodes to bypass the node to be deleted, freeing its memory, and ensuring the continuity of the list.
5. Singly Linked List vs. Doubly Linked List: In a singly linked list, each node points to the next node, enabling traversal in one direction (forward). In contrast, a doubly linked list has nodes with references to both the next and previous nodes, allowing traversal in both directions (forward and backward). The doubly linked list provides more flexibility but requires additional memory for the prev pointer.
6. Circular Linked List: A circular linked list is a special type of linked list in which the last node's next pointer points back to the head node, forming a closed loop. This structure allows circular traversal of the list.
7. Time Complexity of Operations: The time complexity of common operations in linked lists includes:
   • Accessing an element: O(n)
   • Insertion at the beginning: O(1)
   • Insertion at the end: O(n) for singly linked, O(1) for doubly linked
   • Deletion: O(n)

Linked lists are often used in various applications, including:

• Implementing other data structures like stacks and queues.
• Dynamic memory allocation, especially for elements of varying sizes.
• Handling large datasets with the need for efficient insertions and deletions.

Overall, linked lists are valuable data structures due to their dynamic memory management, efficient insertion and deletion operations, and suitability for handling dynamic or varying data. However, their main drawback is the lack of efficient random access to elements.