Linked List: 105 Interview Questions for DSA Success

1. Linked List Basics

• Introduction to Linked Lists
• Creating a Singly Linked List
• Traversing a Linked List
• Inserting at the Beginning
• Inserting at the End
• Inserting at a Given Position
• Deleting a Node by Value
• Deleting a Node by Position
• Deleting the First Node
• Deleting the Last Node

2. Search and Length Operations

• Searching for an Element in a Linked List
• Finding the Length of a Linked List
• Counting Occurrences of a Given Element
• Finding the Middle of a Linked List
• Finding the Nth Node from the End
• Detecting a Loop in a Linked List (Floyd’s Cycle Detection)
• Removing a Loop in a Linked List
• Finding the Start of a Loop
• Checking if a Linked List is Circular
• Checking if a Linked List is a Palindrome

3. Linked List Reversal

• Reversing a Linked List Iteratively
• Reversing a Linked List Recursively
• Reversing a Linked List in Groups of K
• Reversing Alternate K Nodes
• Reversing the First Half of the Linked List
• Reversing the Second Half of the Linked List
• Reverse Nodes Between M and N
• Reverse Every Alternate Node in a Linked List
• Reverse Pairs in a Linked List
• Reverse a Doubly Linked List

4. Linked List with Recursion

• Recursive Approach to Traversal
• Recursive Approach to Search
• Recursive Approach to Insertion
• Recursive Approach to Deletion
• Recursive Merge of Two Sorted Linked Lists
• Recursive Reversal of a Linked List
• Recursive Approach to Flatten a Multilevel Linked List
• Recursive Palindrome Check
• Recursive Segregation of Even and Odd Nodes
• Recursive Pairwise Swap of Nodes

5. Two-Pointer Techniques in Linked Lists

• Finding the Intersection of Two Linked Lists
• Detecting and Removing Loop (Two-Pointer Method)
• Finding the Middle Node (Tortoise and Hare Approach)
• Merging Two Sorted Linked Lists
• Detecting Intersection in Circular Linked Lists
• Reordering Linked List (Odd-Even Nodes)
• Sorting a Linked List Using Merge Sort (Two-Pointers)
• Quick Sort on Linked List Using Two Pointers
• Reversing Nodes in a Linked List with Two Pointers

6. Advanced Linked List Operations

• Merge K Sorted Linked Lists
• Flattening a Multilevel Linked List
• Clone a Linked List with Random Pointers
• Rotate a Linked List Left by K Positions
• Rotate a Linked List Right by K Positions
• Segregate Even and Odd Nodes in a Linked List
• Add Two Numbers Represented by Linked Lists
• Subtract Two Numbers Represented by Linked Lists
• Multiply Two Numbers Represented by Linked Lists
• Divide Two Numbers Represented by Linked Lists

7. Circular Linked Lists

• Introduction to Circular Linked Lists
• Creating a Circular Linked List
• Insertion at the Beginning of a Circular Linked List
• Insertion at the End of a Circular Linked List
• Deletion from a Circular Linked List
• Converting a Singly Linked List to a Circular Linked List
• Splitting a Circular Linked List into Two Halves
• Josephus Problem in Circular Linked List
• Detecting Loop in a Circular Linked List
• Traversing a Circular Linked List

8. Doubly Linked Lists

• Introduction to Doubly Linked Lists
• Creating a Doubly Linked List
• Insertion at the Beginning of a Doubly Linked List
• Insertion at the End of a Doubly Linked List
• Insertion After a Given Node in a Doubly Linked List
• Deletion of a Node from a Doubly Linked List
• Reversing a Doubly Linked List
• Flattening a Doubly Linked List
• Converting a Binary Tree to a Doubly Linked List
• Traversing a Doubly Linked List in Both Directions

9. Specialized Linked Lists

• Skip List Implementation
• XOR Linked List (Memory Efficient Doubly Linked List)
• Flattening a Linked List with Child Pointers
• LRU Cache Implementation Using Doubly Linked List
• Implementing Stack Using Linked List
• Implementing Queue Using Linked List
• Convert Binary Numbers in Linked List to Integer
• Clone a Multilevel Linked List
• Add 1 to a Number Represented by Linked List
• Implementing a Priority Queue Using Linked List

10. Complex Problems on Linked Lists

• Intersection Point of Y-Shaped Linked Lists
• Swapping Nodes in a Linked List Without Swapping Data
• Rotate a Linked List in Blocks of K
• Delete Nodes Which Have Greater Value on the Right Side
• Delete N Nodes After M Nodes
• Flatten a Linked List Where Each Node Has a Next and Child Pointer
• Segregate 0s, 1s, and 2s in a Linked List
• Flatten a Linked List of Linked Lists
• Convert a Sorted Linked List to a Balanced BST
• Rearrange a Linked List in Zig-Zag Fashion

11. More Essential Interview Questions:

• Implement a Function to Merge Two Sorted Linked Lists Without Using Extra Space.
• Find the Intersection Node of Two Linked Lists Using Length Difference.
• Check for Overlapping Cycles in Two Linked Lists.
• Remove Duplicates from an Unsorted Linked List.
• Find and Remove the Kth Node from the End in One Pass.
• Create a Copy of a Linked List with a Random Pointer in O(n) Time.

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