Six Islands
(Published on 21. October 2022, 16:00 by Blobz)
Sudoku rules (sort of) apply -- No row, column, or box contains the same digit more than once.
There are six islands (orthogonally connected regions) each containing the digits 1-6 with no repeats. Each of the given digits belong to a different island from the others.
The islands are separated by a single, orthogonally connected waterway. Note that islands do not touch diagonally, and that the waterway does not contain any 2x2 area. All water cells are EMPTY (contain no digits).
Circled digits (all land cells) indicate exactly how many adjacent cells (up to 8) contain water, and ALL such cells are indicated; that is, non-circled digits will NEVER have that number of adjacent water cells.
The clues outside the grid indicate the sum of island cells along the indicated diagonals.
Have fun, leave a comment if you enjoy the puzzle!
Solution code: Row 2 followed by Row 6 followed by Row 8, entering 0 for water cells.
Comments
on 3. April 2024, 21:04 by Blobz
Rules Clarification.
on 3. April 2024, 20:58 by DiMono
This is a really good puzzle. I would propose a minor edit to the wording of paragraph 3:
"Note the islands do not TOUCH diagonally"
Since you've previously said that the islands are orthogonally connected regions, that establishes "connect" as talking about a single island, rather than two that are connecting with each other. That word change will make the rules more clear.
I would also suggest specifying that water cells are EMPTY rather than merely being worth 0, as that will be more clear for the solution path.
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Thanks for the feedback. I have incorporated your suggested modifications into the rules.
~Blobz
on 2. January 2024, 16:14 by rich_27
I really enjoyed this! It took me a long time with a lot of iterations, due to - I think - the rules being quite ambiguous.
A few things weren't clear to me:
- the islands must contain exclusively the digits 1-6 and so only have six cells each;
- 0 and 7+ cannot be used in islands (were they to have more than six cells);
- the waterway does not need digits placed (water cells are worth 0, but my initial understanding was that they would still need to be populated with digits).
It was still fun trying to solve multiple times with successively looser constraints each time, but it took quite a bit of work to rule out some of those other possibilities.
on 10. March 2023, 18:16 by Felis_Timon
Which cells are counted by the circles?
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Circle cells (all land cells) count adjacent water cells. For example, in theory r1c5 could be from 1 to 5, r3c6 could be from 1 to 8. (4th paragraph)
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So the 8 surrounding cells?
on 21. October 2022, 18:16 by efnenu
The negative constraint does some heavy lifting – thank you for this nice and enjoyable puzzle!
