Solution code: For each row, enter the length of the longest continuous horizontal line of unshaded cells. For each 2x2 room, the number of shaded cells (in reading order). That is, 19 digits in total.
on 19. June 2022, 23:46 by zeneszerzo
I like this one a lot!
on 31. January 2022, 19:42 by SudokuExplorer
@Vebby: Thanks! I'll consider adding thicker borders next time. As Dandelo mentioned, any shade of grey (or black but that's worse) works for answer check.
on 31. January 2022, 15:34 by Dandelo
I use grey instead of dark grey.
on 31. January 2022, 07:12 by Vebby
Very nice! Thanks S.E.!
Small suggestion for such puzzles on Penpa+: Using Edge -> Thicker for borders helps with visibility, especially after some cells are shaded dark.
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