Compass Chaos Construction
(Published on 11. March 2023, 20:08 by Jay Dyer)
I actually set this one about six months ago, inspired by Magnus Josefsson's compass fillomino puzzles, then it got crowded out by other things. Figured it was about time I posted it.
Rules
- Divide the grid into nine regions of nine orthogonally connected cells each. Each row, column, and region contain the digits 1-9 once each.
- If there is an arrow in a cell, the digit in that cell equals the total number of cells belonging to the region the arrow comes from that are in the direction of the arrow. Not all arrows are necessarily given.
Solve in Penpa+ or Sudokupad (beta).
Solution code: Row 4 and column 5.
Comments
on 13. March 2023, 14:39 by DVFrank
Very nice! :^)
on 13. March 2023, 13:41 by thrutch
That was a lot of fun. Like Tilburg, I found the irregular sudoku considerably harder than the region building.
on 13. March 2023, 12:28 by Piatato
Awesome puzzle! Fun throwback to when I discovered Stephane's Compass Sudokus, which I think was my first introduction to chaos constructions. :)
on 13. March 2023, 00:03 by Elliptical
Really fun. I like this rule set even though, for some strange reason, I kept placing the digits in the wrong cells (the cell the arrow comes from instead of the cell with the arrow). Then I would have to back track and find my mistake. I lost count of how many times I did that. If only I had a brain...,
on 12. March 2023, 19:48 by udukos
Lovely puzzle! Thanks
on 12. March 2023, 16:19 by Agent
Some lovely region building logic in this puzzle!
on 12. March 2023, 15:54 by Tilberg
Wow. The compass part was actually easy compared to the irregular sudoku part. Didn't expect that! Very nice puzzle.
on 12. March 2023, 12:12 by polar
Nice puzzle thanks!
I very much second Jesper's recommendation for Stephane's compass puzzles too.
@Piatato: they can be in different regions
on 12. March 2023, 11:41 by Piatato
Ooh, I'm excited to see a new Compass sudoku! One question: must f ex r1c5 and r2c4 be in the same region, or can different regions point into the same cell?
@Piatato: Those cells do not need to be in the same region.
on 12. March 2023, 00:20 by Jesper
Very fun and smooth region construction logic!
By the way, there are actually a couple of puzzles by Stéphane Bura with pretty much exactly this ruleset (I think he called them Exploded Compass Sudoku). They were a source of inspiration for Magnus when creating the Compass Fillominos.
