This is a Kurotto puzzle.
Rules of Kurotto:
- Shade some cells to form connected groups of shaded cells.
- Circled cells are unshaded. If they have a number in them, that number tells you the sum of the sizes of adjacent groups.
An example Kurotto puzzle (on a square grid), and its unique solution:
(In this puzzle, both squares and octagons can be shaded, and each square or octagon counts as a single cell for the number clues.)