6x6 Loop-Pack: Volume 3 (Region Sums, Whisper, Extra Regions)
(Published on 28. April 2024, 20:17 by gdc)
This is the follow-up to Volume 1 and Volume 2. It should be similar to Volume 2 in difficulty. Each of these puzzles uses "loop-finding" and "sight-lines".
- Normal Sudoku rules apply.
- Draw a one-cell-wide loop of orthogonally connected cells. The loop can't touch itself, not even diagonally.
- Circles are on the loop. Squares are not on the loop.
- A digit in a circle/square counts how many cells of the same type (loop/non-loop) it sees in the row and column, including itself. The other type blocks vision.
Each puzzle contains an additional loop-constraint that is inspired by common variant-sudoku clues (such as modular lines). Click on the images to solve the puzzles on SudokuPad. If you are new to loop-puzzles or sight-lines, there are examples (with images) below. Thanks to all the testers!
Explanation: Loops
Drawing an orthogonal loop means that each cell on the loop shares an edge with exactly two other cells on the loop. Since the loop can't touch diagonally, the "interior" of the loop is also orthogonally connected (i.e. "edge-connected").
Explanation: Sight-Lines (Circles, Squares)
Circles count the number of seen loop-cells in the same row and column with non-loop cells blocking the vision. They always count themselves so a sight-line clue can never be 0. Squares do the same but they count non-loop cells. The images below show examples of valid fills for circles and squares. Colored cells are seen by those clues.
Solution code: The last three digits from row 6 of each puzzle (3 digits each, 9 digits total)
Comments
on 8. October 2024, 21:43 by ThymePass
Another lovely set of puzzles and another educational set of puzzles! Thanks for putting these together.
I agree with the other commenter; the extra regions puzzle was great :)
on 28. June 2024, 23:59 by QuiltyAsCharged
Great puzzle packs! Having the same common rules for all puzzles works out nicely. Extra Regions was my favorite one from all the packs, and perhaps surprisingly I found it the easiest of the three puzzles in this volume.
on 22. May 2024, 09:48 by SparklePuzzle
Good puzzles. For extra regions it might be useful make the rule explicit that the line must be *entirely* made up of the extra regions. I was stumped for a while thinking the line only needed to include one such extra region
on 30. April 2024, 20:10 by LehanLehan
It was hard to solve it properly without bifurcation but it was a great pleasure, waiting to see more of the pack.
on 29. April 2024, 07:39 by yttrio
These felt a bit tougher than the first couple of packs (especially the extra regions puzzle), but were still very fun and had some nice logic throughout!
