How to play
- Each clue lists the lengths of the filled blocks in that row or column, in order. “3 1” means a block of three, then at least one gap, then a block of one.
- Click or tap to fill a cell. Right-click, or switch to Mark ✕, to cross out cells you know are empty.
- Drag across cells to fill or mark several at once.
- Clues fade when their line is complete. The puzzle is solved when every clue is satisfied.
Solving techniques
- Big blocks first. In a 10-cell row, a clue of 8 must cover the middle six cells, wherever it starts.
- Add it up. For “4 5” in a row of 10, the blocks plus one gap need exactly 10 cells, so the whole row is determined.
- Use crosses. Once a row is complete, mark the remaining cells so they help the columns.
- Edges are clues. A filled cell next to the border must belong to the first block in that line.
Sizes
5×5 takes a minute or two and is perfect for learning. 10×10 is the classic size. 15×15 needs patience and careful marking.
FAQ
Is there only one solution?
Puzzles are generated randomly, so occasionally two grids fit the same clues. Any grid that matches every clue counts as solved.