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Overview
Basic Data Structures
Basic Algorithms
Same Direction
Opposite Direction
Sliding Window
Cycle Finding
Speedrun
DFS on Tree
Binary Search Tree
Combinatorial Search
Additional States
Aggregation and Memoization
Additional Practices
Speedrun
Vanilla BFS
Matrix as Graph
Implicit Graph
Directed Graph / Topological Sort
Weighted Graph
Minimum Spanning Tree
Introduction
Constant Transition
Grid
Dual-Sequence
Non-constant Transition
Knapsack, Weight-Only
Knapsack, Weight+Value
Topological Sort
Additional Practices
Disjoint Set Union | Union Find
Data Structure Design
Segment Tree
Monotonic Stack
Line Sweep
Tree Traversal without Recursion
Amazon OA
Microsoft OA
Google OA
Editorials
Learn how transformers work with zero ML background
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Dynamic Programming Module Expansion
Fixed various minor bugs and improved overall stability.
We're excited to announce a new course: How LLMs Work — a comprehensive guide for developers who want to understand large language models from the ground up, without needing a machine learning background. The course covers four modules:
Each module includes interactive visualizations and clear code examples, helping you build intuition for how modern AI systems actually work.
New Foundation Course
Add Complete button in lite problems page.
✨ Upgraded the interview-guides page with improved layout and content updates.
New Feature: Study Notes
We've added a powerful note-taking system to help you organize your learning! Create and save notes for any article or problem with Markdown support, real-time preview, and auto-save functionality. Your notes are automatically synced and can be accessed from your dashboard.