Normal sudoku rules apply. Shade some cells in the grid. Shaded cells cannot share an edge with each other. The unshaded cells must form a single orthogonally-connected area. The digit contained in each circle indicates how many cells must be shaded in that 3x3 box. A contiguous line (vertical or horizontal) of unshaded cells cannot span two 3x3 region borders. The digits in a cage may not repeat and must sum to the value given in the top left of the cage. Shaded cells do not contribute to the total.