A playful little place to learn to code.
Follow the patterns, make a few mistakes,
and leave a little better than you arrived.
No account needed to start. Practice as a guest, or create a free account to sync and join leaderboards.
Meet Tik. Big fan of your next attempt.
Start with the basics. The big ideas can wait their turn.
Variables, loops, functions and conditionals
Variables and expressions / Conditionals / Loop accumulators / State in a loop / Helper functions
Arrays and strings
Adjacent array positions / String runs / Stable array filtering / Nested array traversal / String scanning
Maps, sets, counting and sorting
Frequency maps / Set membership / Set intersection / Map grouping / Comparator sorting
All nine chapters are ready: 500 original challenges in 54 focused units.
A short primer, a clear task, and just enough direction. Pick your language and find the first thread.
Type an idea. Run a test. Follow the little clues. Hints are here when you need a nudge.
Your notes, your progress, your honest attempts. Come back later and make the pattern stick.