Sudoku
Generate a puzzle with exactly one solution, then help me find it.
IntermediateWeb appGame12–26hAI-buildable 3/5no setupworth shipping
Sudoku with pencil marks, validation and hints. The deep part is generation: producing a puzzle with a unique solution at a target difficulty means writing a solver first and using it to verify each clue removal.
UI
Logic
Useful
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Core features · 7
- Generated puzzles with a guaranteed unique solution
- Difficulty levels with meaningfully different clue counts
- Pencil marks for candidate numbers
- Conflicts highlight as you enter numbers
- A hint reveals one cell with its reasoning
- Undo and a full reset
- Progress persists across reloads
The interesting part
- Generating a puzzle with a provably unique solution
- Rating difficulty meaningfully rather than by clue count alone
- A hint that explains its reasoning instead of just revealing
Once it works
- Auto-update pencil marks as cells are filled
- Rate difficulty by the solving techniques required
- Add a puzzle import by photo or string
Suggested stack
reacttypescripttailwindlocalstorage