In these puzzles, your goal is to create isolated white areas surrounded by black walls, such that each white area has only one number and the number of cells in a white area is equal to the number in it.
A few other rules must be kept in mind as you solve: Cells containing numbers cannot be blackened, and the cells that are blackened must be linked into a continuous wall, as in the example at right. Also, you cannot form a block of black cells 2×2 or larger. Best place to start? Pick a 1, and draw in black squares on all four of its sides.