Linked List Visualizers

20

Step through every Linked List problem with animated runtime state, source highlighting, and curated test cases. Built for coding-interview prep and durable algorithmic intuition.

Add Two Numbers
Simulate digit-by-digit addition with carry over linked lists.
Math & Pointers
Adding Nodes to Linked List
Insert nodes at specific indices by traversing to index - 1.
Insertion
Deleting Nodes in Linked List
Bypass a node by pointing curr.next to curr.next.next to remove it.
Deletion
Design Linked List
Understand how to maintain head, tail and list size when designing a linked list.
Class Design
Intersection of Two Linked Lists
Find the merge point by swapping pointers to align distances.
Two Pointers Reset
Introduction to Linked List
Learn the basics of linked list traversal using a current pointer.
Traversal
Linked List Cycle
Detect cycles using Floyd's Tortoise and Hare algorithm.
Fast & Slow Pointers
Linked List Cycle II
Find the start of a cycle using phase 1 and phase 2 intersection.
Fast & Slow Pointers
LRU Cache
Design a data structure with O(1) operations that evicts the least recently used item using a Hash Map and Doubly Linked List.
Linked List
Merge Two Sorted Lists
Combine two sorted lists picking the smallest heads sequentially.
Two Pointers Merge
Middle of the Linked List
Use a slow and fast pointer to find the middle node efficiently.
Fast & Slow Pointers
Odd Even Linked List
Group odd and even indexed nodes separately, then combine them.
Two Pointers Interleave
Palindrome Linked List
Check for palindromes by reversing the second half and comparing.
Fast & Slow + Reverse
Remove Duplicates from Sorted List
Bypass duplicates since they are adjacent in a sorted list.
Single Pass Traversal
Remove Linked List Elements
Remove specific values from a list using a dummy node approach.
Dummy Node
Remove Nth Node From End of List
Maintain an n-gap between two pointers to find the node perfectly.
Two Pointers Gap
Reorder List
Reorders a Linked List by splitting it into two halves, reversing the second half, and merging them alternately.
Linked List
Reverse Linked List
Iteratively reverse a linked list using prev, curr, and next pointers.
In-Place Reversal
Rotate List
Form a circular list then break it at the correctly calculated point.
Modulo Math & Pointer
Swap Nodes in Pairs
Swap adjacent nodes iteratively by keeping track of the previous node.
Pointer Swapping