Beacon Lighthouse (Chaos Construction - Phistomefel Tribute)
(Published on 12. December 2021, 21:38 by purpl)
Rules:
Each row, column, and region must contain the digits 1-9 once each.
The regions first need to be determined. Every region is a set of nine orthogonally connected cells.
A digit in a circle indicates the number of borders between regions it sees in its row and column. Note that the edge of the grid does not count toward this total.
The border between r2c3 and r3c3 is a region border and indicates that these two cells belong in different regions.
Remark: There is no negative constraint regarding the circle, i.e. there can be uncircled cells containing a digit that equals the number of edges seen in the respective row and column.
Links:
Solution code: Row 8 followed by column 9 (left to right, top to bottom, 18 digits, no spaces)
Comments
on 6. September 2023, 17:41 by friqlyman
As someone who would like to get into solving harder chaos construction puzzles I enjoyed this a lot! Felt approachable and was fun throughout! Thanks a lot!
on 21. October 2022, 06:12 by filuta
I liked the unusual way the regions were built (and how their shapes were used). No pert of the puzzle felt to me inappropriately hard (or easy). Good and fun puzzle.
on 3. September 2022, 21:07 by PrimeWeasel
Very enjoyable! I don't think the irregular part is harder than the lighthouse part (mainly cause I screwed up the lighthouse logic and sailed through the irregular part), they felt quite consistent to me.
on 13. December 2021, 20:48 by purpl
@henrypijames I definitely understand where you are coming from. Irregular sudoku can certainly give rise to a lot of difficult logic. I decided to keep the one very difficult irregular sudoku step to retain an earlier step of the lighthouse. Perhaps that was a mistake as it made the puzzle quite a bit more difficult than it needed to be. Thank you for your feedback.
on 13. December 2021, 06:24 by henrypijames
The lighthouse logic is nicely applied and indeed somewhat easier, but the resulting sudoku is still very harder - disproportionately so in my opinion.
on 12. December 2021, 23:51 by Steven R
Very nice!
