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Learn algorithms by pattern,
not by memorization.
A free, open curriculum for CS students preparing for tech interviews. Master sliding windows, two pointers, graphs, dynamic programming, and more — with AI-guided feedback on every submission.
Pattern-first learning
Each problem is grouped into a recognizable pattern so you build intuition, not just solutions.
AI interviewer feedback
Submit code and get hints — never answers — from an AI persona modeled after top-company interviewers.
Conceptual MCQs
After each pattern, short quizzes test time/space complexity and edge cases before you move on.