Overview of Linked List

 Overview of Linked List

A linked list is a fundamental data structure in computer science that represents a linear collection of elements.

Unlike arrays, linked lists do not store elements in contiguous memory locations.

Instead, each element (node) in a linked list contains a data element and a reference (link or pointer) to the next node in the sequence.

The last node typically points to null, indicating the end of the list.

 

key concepts related to linked lists:

Basic Components of a Linked List:

 

1. Node:

   - A fundamental building block of a linked list.

   - Contains two fields: data and a reference (or link) to the next node.

 

2. Head:

   - The first node in the linked list.

   - Serves as the entry point for accessing the elements in the list.

 

3. Tail:

   - The last node in the linked list.

   - Its "next" reference is usually set to null.

 

 Types of Linked Lists:

 

1. Singly Linked List:

   - Each node points to the next node in the sequence.

   - Efficient for forward traversal.

      Head -> Node1 -> Node2 -> Node3 -> ... -> Tail -> null

  

2. Doubly Linked List:

   - Each node has references to both the next and the previous nodes.

   - Enables backward traversal.

      Head <-> Node1 <-> Node2 <-> Node3 <-> ... <-> Tail <-> null

 

3. Circular Linked List:

   - The last node points back to the first node, forming a closed loop.

   Head -> Node1 -> Node2 -> Node3 -> ... -> Tail -> Head

 

 Linked List Operations:

1. Insertion:

   - Adding a new node to the list.

   - Three scenarios:

     - Insert at the beginning: Adjust the "next" reference of the new node and update the head.

     - Insert in the middle: Adjust the "next" references of the surrounding nodes.

     - Insert at the end: Update the "next" reference of the current tail and set the new node as the new tail.

 

2. Deletion:

   - Nodes can be deleted from a linked list.

   - Deleting the first node requires updating the head.

   - Deleting the last node involves updating the reference of the second-to-last node.

   - Deleting a node in the middle requires adjusting the references of neighboring nodes.

 

3. Traversal:

   Traversing a linked list involves visiting each node in the sequence.

   - This is typically done using a loop that starts at the head and iterates through the nodes until the end is reached.

 

4. Search:

   - Finding a specific value in the linked list.

   - Requires traversing the list until the value is found or reaching the end (null).

 

5. Updation:-

   - Finding a specific value in the linked list.

   - Requires traversing the list until the value is found or reaching the end (null).

  - Replace old value to new value.

 

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