Friendly Snake in the Fog
(Published on 26. September 2023, 17:14 by Scojo)
- Normal sudoku rules apply: Place the digits 1-9 once each in every row, column, and 3x3 box.
- Fog of War: Placing a correct digit in a cell will clear the fog from the surrounding cells. Guessing is not allowed!
- Double Friendly Cells: Identify 9 Double Friendly Cells in the grid such that there is one Double Friendly Cell in every row, column, and 3x3 box. A cell is Double Friendly if its digit matches exactly two of the following: its row number, column number, or box number.
- Draw a snake through the grid beginning at row 1 column 1 and ending at row 9 column 9. The snake cannot touch itself, even diagonally. All Double Friendly Cells must be visited by the snake.
- A cell with a circle is on the snake, and its digit represents the distance along the snake from the circle to the closest Double Friendly Cells in both directions.
- A cell with a square is not on the snake, and its digit represents the number of snake cells in the up to 8 cells surrounding the square.
Solve in SudokuPad
Solution code: Row 8
Comments
on 16. April 2024, 15:11 by Krokant
A snake in the fog doesn't sound very tempting at first, but it's surprisingly fun. :)
on 16. April 2024, 13:31 by carl.gershman
So, you changed starting fog, and what to do now? Without any other clues, it's unsolveable? Or I too stupid? I can't place any number, I can only find supposed places for friendly cells, but it give me nothing. Give me a hint maybe?
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The key is that Double Friendly cells can only match exactly two of its row, column, or box number. Matching all three is not allowed. -Scojo
on 12. November 2023, 02:27 by Scojo
Changed starting fog, changed solution code.
on 26. October 2023, 11:31 by Geb
Took me a few minutes to realise the trick to start but from then on it was fantastic fun.
on 22. October 2023, 09:01 by Montikulum
Very nice puzzle but ~40 solution digits? Really?
on 17. October 2023, 20:32 by Chad
smooth and approachable despite the ruleset. Very fun puzzle!
on 28. September 2023, 20:15 by mrlemmelook
Tricky start for me, but absolutely loved it!
I also experienced alot of missing digits bug :/
But i liked the snake solution code :P
on 27. September 2023, 20:27 by MartinR
Once the implications of the double friendly cells are seen, works quite nicely.
I also had the same scanning issue as Flinty, I think it was down to the word "closest" as I (incorrectly) thought "closest of two directions" - maybe "next df cell" might reduce confusion?
Also agree with comments regarding length of solution code!
on 27. September 2023, 14:52 by Flinty
I didn't initially appreciate the power of "both directions" and wrongly inferred it meant "either direction". Very nice puzzle :)
on 27. September 2023, 09:50 by Schma
Beautiful Puzzle. It took me quite a while to spot the break-in but it was a very smooth solve
on 27. September 2023, 00:58 by ordnanceordinance
given digits glitching out? Is it this puzzle or FOW in general?
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It wasn't glitchy for me, but I know the software has had some issues with fog of war in the past. Hope it didn't affect your solve too badly. - Scojo
on 26. September 2023, 21:56 by Starlight
Very fun puzzle and definitely approachable. I was intimidated by the rules but it was smooth and I always knew how to progress
on 26. September 2023, 21:01 by aerenhart
Easy snake, hard (for me) number filling. Must not be my day scanning lol.
Agree with Imdemasi, borderline criminal, that solution code!
Thank you for the puzzle :)
on 26. September 2023, 17:58 by lmdemasi
Scojo, I can't believe you made me type that many digits for the solution. :/
