Interview prep
Everything for a coding interview in one place. The lessons are the same ones as the rest of the site, organized here for an interview.
Study tracks
5 tracksOrdered plans that build pattern by pattern. Sign in to track your progress.
Company prep
9 companiesWhat each company's loop looks like, and the patterns and problems to drill for it.
Problems
51 problemsThe most-asked interview problems, each with its approach, complexity and the mistake to avoid.
Practice
48 lessonsPredict a lesson's next step, then write its code. Checked by running it against the model.
Review
DailySpaced repetition of the checkpoints and flashcards from your lessons. Needs an account.
Tracks
Essential StarterThe 12 problems every interview prep should begin with.Arrays & StringsHashing, two pointers, sliding window, and prefix sums.Graphs & TreesBFS, DFS, topological sort, and union-find.Dynamic ProgrammingFrom 1D recurrences to classic DP tables.Stacks, Heaps & IntervalsMonotonic stacks, priority queues, and interval sweeps.