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Learn Doubly Linked List with visual DSA lessons

Learn Doubly Linked List with 2 DSA patterns and 9 visual lessons. Follow step-by-step animations and synced C#, Python, and Java code.

Each node points both forward and backward.

Basic DLL Operations

Insert, delete, reverse, and design caches with two-way links.

Implement Doubly Linked List Easy · Visible link rewiring
Insert a node in a doubly Linkedlist Easy · Visible link rewiring
Delete a node from a doubly Linkedlist Easy · Visible link rewiring
Reverse Doubly Linked List Easy · Visible link rewiring
LRU Cache Medium · Visible link rewiring
LFU Cache Hard · Visible link rewiring

Merge / Sort / Reorder

Merge, flatten, or transform a two-way node chain.

Merge Two Sorted DLLs Medium · Visible link rewiring
Flatten Multilevel DLL Medium · Visible link rewiring
Convert DLL to Binary Tree Medium · Visible link rewiring