Lilly Tech Systems
LeetCode Top 50 for AI Engineers
The 50 most frequently asked LeetCode problems at top AI/ML companies — Google AI, Meta AI, OpenAI, DeepMind, Amazon ML, and more. Each problem includes a complete Python solution, detailed explanation, time/space complexity analysis, and ML context showing where these patterns appear in real AI systems.
Your Learning Path
Work through the problems by difficulty and category. Each lesson groups related problems so you can master the underlying patterns, not just memorize solutions.
1. How to Use This Course
Study plan, pattern recognition strategy, time targets per difficulty, and how to maximize your prep for AI/ML company interviews in 4 weeks.
2. Easy Problems (1-10)
Two Sum, Valid Parentheses, Merge Sorted Lists, Best Time to Buy/Sell, Valid Palindrome, Linked List Cycle, Climbing Stairs, Binary Tree Inorder, Maximum Subarray, Contains Duplicate.
3. Medium: Arrays & Strings (11-20)
3Sum, Container With Most Water, Longest Substring Without Repeating, Product of Array Except Self, Group Anagrams, Merge Intervals, Sort Colors, Subarray Sum K, Rotate Array, Spiral Matrix.
4. Medium: Trees & Graphs (21-30)
Level Order Traversal, Validate BST, Number of Islands, Course Schedule, Word Search, Clone Graph, Binary Tree Paths, Kth Smallest in BST, Serialize/Deserialize Tree, Lowest Common Ancestor.
5. Medium: DP & Design (31-40)
Coin Change, Word Break, House Robber, Unique Paths, Decode Ways, LRU Cache, Min Stack, Top K Frequent Elements, Meeting Rooms II, Task Scheduler.
6. Hard Problems (41-50)
Median of Two Sorted Arrays, Merge K Sorted Lists, Trapping Rain Water, Longest Palindromic Substring, Edit Distance, Word Ladder, Sliding Window Maximum, Largest Rectangle in Histogram, Regular Expression Matching, Minimum Window Substring.
7. Pattern Recognition Guide
Map every problem to its core pattern (sliding window, two pointers, BFS/DFS, DP, etc.), learn to identify patterns from problem descriptions, and build a mental decision tree.
8. Study Plan & Tips
Complete 4-week study plan with spaced repetition, daily targets, mock interview strategy, and a comprehensive FAQ for AI/ML coding interviews.
What You Will Learn
By the end of this course, you will be able to:
Solve the Top 50
Master the 50 LeetCode problems most frequently asked at AI/ML companies. Every solution includes full Python code, step-by-step walkthrough, and complexity analysis.
Recognize Patterns
Map each problem to its underlying pattern — sliding window, two pointers, BFS/DFS, dynamic programming, greedy — so you can solve new problems you have never seen before.
Connect to ML Systems
Understand where these data structures and algorithms appear in real AI/ML systems: model serving, feature stores, training pipelines, graph neural networks, and more.
Ace AI Company Interviews
Follow a proven 4-week study plan with spaced repetition and time targets. Know what to expect at Google AI, Meta AI, OpenAI, DeepMind, and other top AI companies.