Some squares hold a circled number. Shade other squares so that, for every circle, the shaded groups touching it along a side add up to exactly its number. A group is all the shaded squares joined to each other side by side, however far it reaches.
A circle of 0 touches nothing shaded. A circle of 5 might touch one group of five, or a group of two on one side and three on another.
Start with zeros and with circles that are boxed in — they can only grow in one direction.
Shade squares so every circled number equals the total size of all the shaded groups touching that circle.
The full guide, with a worked example and common mistakes: How to play Cluster Count.
No — only squares that share a side.
Yes — and its whole size counts for each circle it touches.
Yes — every puzzle here is checked to have exactly one solution.
Open the Cluster Count Solver, type the circled numbers and press Solve.