Curated practice
Choose a sheet, then code in one workspace.
Lists are for discovery. Every problem opens in the same local-first coding workspace with language-specific starter templates and IndexedDB-backed drafts.
Sheet67 problems
Ratta 67
67 essential easy and medium problems. Covers every core pattern — arrays, trees, graphs, DP, and more — without the hard-mode spikes.
Sheet75 problems
Blind 75
The classic interview sheet. A compact set of foundational problems across arrays, stacks, linked lists, and core patterns.