DSA practice that grades like a real judge.
A curated problem catalog by difficulty, graded against hidden test cases in your language — plus animated visualizers that show the pattern, not just the question.
DSA PRACTICEDSA Practice Platform, built to actually help
Sample test cases pass, then the real judge fails you.
Every submission runs against real hidden test suites — pass/fail counts per language, not just the visible sample.
You solve a problem without ever seeing why the technique works.
The DSA visualizer animates patterns like two-pointer and sliding window step by step, unlocked topic by topic.
Practice fizzles out after a few days.
A day-streak, streak calendar, and difficulty-donut keep the habit — and the gaps — visible.
No way to know where you actually rank.
A live leaderboard ranks you against everyone else solving on krackit.
Get started in three steps
Pick a problem
Filter the catalog by difficulty and topic.
Solve in the editor
Write and run your solution in-browser, in the language you choose.
See real results
Hidden-test-suite grading, streak tracking, and leaderboard rank update instantly.
DSA Practice Platform, answered
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