This is an example of a completed Range puzzle. The aim is to fill the grid with black and white cells
so that these conditions are met,
- Each numbered cell can 'see' that many white squares in total by looking in all four
horizontal/vertical directions, and counting itself. Black squares block the view.
- No two black squares can be next each other horizontally or vertically (diagonally is
ok).
- The white cells must form one contiguous whole, i.e. it is not allowed for one group
of white cell(s) to be separated from any other white cells by black cells.