Logic Masters Deutschland e.V.

Rules:

Normal Sudoku rules apply. Shade some cells so that all areas of orthogonally connected shaded cells are rectangular and all areas of orthogonally connected unshaded cells are not rectangular. (Yes, a square is a rectangle.) A digit in a circle equals the size of its group of shaded/unshaded cells. Digits may not repeat within such a group, and a killer clue is the sum of the digits in the group. Note: a group can have zero, one, or more than one of each clue type.

Solve:

• SudokuPad