Mountain view sudoku
(Eingestellt am 6. März 2023, 11:32 Uhr von Nylimb)
Normal sudoku rules apply: Fill the grid with digits from 1 to 9, so that every row, column, and 3x3 box contains each of the 9 digits exactly once.
In addition, there is a mountain visible in the grid. Its peak is at the 9 in the central box. The mountain consists of all cells which can be reached from the peak by repeatedly moving from a cell to an orthogonally adjacent cell containing a smaller digit. (See example below.)
Shaded cells are in the mountain; unshaded cells are not.
I've wondered for a while if knowing the shape of the mountain and all the digits within it could lead to a unique solution. I was very surprised to discover that just knowing the shape could be enough, as in this puzzle.
You can solve this in Penpa or in the CTC-app.
As an example of the mountain definition, in the grid below the mountain is shaded and a path is drawn in red from the peak to another mountain cell.
If you want to solve an easier puzzle of this type first, try Introduction to mountain sudoku. And if you like this puzzle, you might also like my other mountain sudokus.
Lösungscode: Row 1 and row 2.
Kommentare
am 18. März 2023, 02:38 Uhr von SimplePurpleFrog
Wow, great logical puzzle. Very interesting how deductions increase slowly in difficulty.
am 15. März 2023, 22:21 Uhr von Bankey
Fun puzzle. Thanks, @Nylimb :)
am 9. März 2023, 12:18 Uhr von Qodec
Loved it from start to finish! Beautiful!
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@Qodec: Thank you!
am 7. März 2023, 13:51 Uhr von Franjo
The mountain is a volcano! The higher we climb the hotter is the temperature. Thank you so much for sharing this lovely puzzle!
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@Franjo: Thanks! I'm surprised that so many more people have solved this one than my previous mountain puzzles.
am 7. März 2023, 05:49 Uhr von Allagem
It's amazing how this puzzle uses the same ruleset as your previous Mountain Sudokus, and yet this one has a totally unique feel because the shape of the mountain has been given. The constraint operates in reverse here! Another fantastic entry to the Mountain series :)
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@Allagem: Thanks. I've tried to use different logic in each of them so far. For now at least, I've run out of ideas for how to do that.
am 7. März 2023, 02:22 Uhr von topoi
Absolutely stellar puzzle! A joy from start to finish. Hope you get a feature on CtC or somewhere similar, if that’s the kind of thing you like.
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@topoi: Thanks. I think I'll suggest one of the mountain puzzles to CtC, but haven't decided which one yet.
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Just finished the series! Thanks for these great puzzles.
IMO, this is the best of them. It really allows the mountain logic to shine for itself. And its so cool to see how you get a unique solution from the mountain placement.
am 7. März 2023, 00:26 Uhr von farodin64
I climbed my first mountain and enjoy the great view, thanks for that!
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@farodin64: I'm glad you liked it.
