Get Your Bearings
(Published on 8. January 2026, 00:26 by EdTheAlchemist)
Sudoku: Normal Sudoku rules apply.
Compass:
- The digits 1 through 8 represent directions, starting at 1 and going clockwise around the compass. For example, if 1 were south-east, then 2 would be south, 3 south-west and so on round to 8 being east.
- You must determine which direction is represented by 1 to start the compass.
Hiking Trails:
- Each circle whose digit is 9 is a reservation and has no trail leaving it or entering it.
- Each circle whose digit is 1 to 8 starts a trail, where the number of cells on the trail, NOT counting the circle itself, is equal to the digit in the circle.
- Every step from one cell to the next along the trail, including the first step, moves in the direction indicated by the digit in which the step starts, which cannot be 9. (The last digit of a trail may be any digit, including 9.)
- Trails never cross each other, share cells with other trails or re-visit the same cells at any point; this includes starting circles.
For example, this is a possible trail if the direction 1 represented south-east:
Signposts:
- An arrow indicates that the number of digits on trails in its row or column (including circles at the start of trails, but NOT including reservations) is equal to the first digit in that row or column from the direction of the arrow.
- Negative constraint: ALL signposts are given.
Solution code: Row 6
Comments
yesterday, 17:17 by henrypijames
I think an example with two trails would be much better, because it's still not clear to me whether two trails can have different compasses, or all 1s must point to the same direction once one of them is fixed.
Also, while the rules forbid trails to "cross each other", they don't forbid a trail to cross itself. Is it actually allowed?
on 9. January 2026, 20:28 by EdTheAlchemist
Hopefully this will add a visual example of the rules!
on 9. January 2026, 15:08 by henrypijames
The ruleset is in dire need of a graphic example.
Like, if a trail goes in one direction only, how could it ever revisit a cell?
on 8. January 2026, 14:59 by EdTheAlchemist
I'm interested to know if you used the negative constraint in your solve! I agree that only one of the arrows is strictly needed, but my solve path needed the negative constraint (hence I added the other arrows).
on 8. January 2026, 11:01 by ShadyAshley
This ruleset is very original and a lot of fun, and the solve path was very elegant and pleasant. Wonderful puzzle!
on 8. January 2026, 04:20 by bansalsaab
That ruleset was really fun. I think i only used row 6 arrow though.
on 8. January 2026, 02:39 by zeniko
That‘s an interesting ruleset and a good challenge. Thanks for sharing.
What initially confused me a bit was what „starting the compass“ meant. That part of the phrasing could probably just be omitted (we simply have to determine the direction for the 1s).
