Narrow Cave Sudoku Deconstruction [4x4]
(Published on 13. November 2023, 01:23 by Christounet)
I was planning to publish this puzzle as an example for a full size 9x9 deconstruction I am preparing. I usually wouldn’t publish it as a standalone. The reason I am doing it is because I want to make sure the way of solving this doesn’t feel too awkward, as it involves a kind of double coloring (for the deconstruction, and for the cave). If it gathers enough positive feedback, I’ll keep setting the bigger one and release it later. I really enjoy the fun logic this ruleset allows, and I am confident others will ! Below the puzzle is a diagram demonstrating the rules and suggesting ways of notating the deconstruction (cages, circles, crosses) to avoid a visually painful double coloring.
The puzzle :
Rules :
- Normal sudoku deconstruction apply : Fill the grid with four non-overlapping 2x2 square regions, such that each region contains the digits 1-4 once each and no digit repeats in any row or column. Cells outside regions do not contain digits.
- Narrow Cave : the whole 5x5 grid must form a valid cave : shade some cells in the grid so that all shaded cells (the walls) are orthogonally connected to the edge of the grid, and all unshaded cells (the cave) form an orthogonally connected area. No 2x2 block may be entirely unshaded.
- Clues : numbers in the top left corner of a cell are ambiguous clues.
- If a clue is in an unshaded cell (cave), it indicates the sum of the digits that are seen in all orthogonal directions from this cell. The cell with the clue counts once in this sum. Walls obstruct the view. Within the field of vision of a clue, digits may not repeat.
- If the clue is in a shaded cell (wall), it indicates the number of cells of that area of orthogonally connected shaded cells.
Diagram of a deconstruction inside a narrow cave grid :
Solution code: Row 4 and column 4 of the grid. For each cell : if it is in a region, the value of the digit in the cell; if it is outside of a region, its shading (S for shaded, U for unshaded). For the exemple diagram, it would be : 3241S4321U
Comments
on 16. November 2023, 18:38 by LehanLehan
Very beautiful, interesting complex logic,but was hard enough;I think the large grid would be too much for me to handle,but anyway thank you very much for the puzzle.
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@LehanLehan : Nice, I am glad you enjoyed this little challenge ! I hope you'll try the bigger puzzle when it's out. Having solved this little one should help you with the basic mechanism of the logic of this ruleset.
on 14. November 2023, 07:48 by KNT
awesome warmup!
on 13. November 2023, 23:07 by lerroyy
Cool little puzzle!
on 13. November 2023, 22:24 by Myxo
Very cute puzzle! I look forward to the big one :)
on 13. November 2023, 22:02 by Jesper
Cool, looking forward to the bigger one!
on 13. November 2023, 19:22 by Agent
Neat puzzle, very cool setup!
on 13. November 2023, 16:01 by goodcity
Really good puzzle !
Nice logic used during the solve. Would love to see more puzzles of this type !
on 13. November 2023, 15:53 by h5663454
A slightly more difficult... um... warm-up puzzle?
I believe this should be in preparation for bigger puzzles, looking forward to the day it is released!
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@h5663454 : Exactly, this is meant to serve as a warm-up and a test for the particular way of solving with this ruleset. I figured it had enough nice logic to be published as a fun easy little snack. Now I can already say, based on the positive feeback, that this will definitely be followed by a more challenging full scale puzzle (i.e. 11x11 deconstruction).
on 13. November 2023, 13:58 by Piatato
Lovely!
on 13. November 2023, 11:11 by Mr_tn
Very nice logic! I'd love to see what this ruleset has to offer on a larger grid.
on 13. November 2023, 07:04 by Christounet
Fixed example image.
on 13. November 2023, 03:11 by Lavender Gooms
I never would have thought of using circles in Sudokupad to additionally indicate regions, so the example was helpful. The puzzle itself wasn't awkward at all, it was quite a nice solution path. Would enjoy seeing the potential bigger one.
