SSS (Sundoko Snake Shape) by Yuki Kawabe

SSS by Yuki Kawabe

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or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode and the linex mode where left click+drag draws lines and right click marks X’s)

Theme: Logical

Author/Opus: This is the 3rd puzzle from guest contributor Yuki Kawabe.

Rules: Combination of Sundoko, Snake, and Shape puzzle styles.

Sundoko: Shade some cells to make sunglasses, consisting of a bridge (a given line, in red) and two lenses made out of orthogonally connected cells that are symmetric with respect to the perpendicular bisector of the bridge. Two lenses may not share an edge, but can intersect at a point. Cells with the bridges are not shaded, except at the bridge ends. Numbers in the grid are unshaded, and indicate the total count of unshaded cells connected vertically and horizontally to the numbered cell, including the cell itself.
Sundoko example:

Sundoko Example

Snake: Shade some cells to create a one-cell wide snake in the grid that does not cross or touch itself, not even diagonally. The snake starts and ends at the black circles and must pass through all white circles.
Snake example:

Snake Example

Shape: Place each of the given shapes into the grid exactly once (rotations and reflections allowed). Shapes cannot touch each other, not even diagonally.
Shape example:

Shape Example

SSS: In SSS, shade some cells to make sunglasses, create a single snake, and place all of the shapes in the grid. Shaded cells of different categories (sunglasses, snake, shapes) cannot share an edge. Number clues referring to unshaded cell counts consider all three categories of objects as shaded cells in this hybrid.

Or see this example:

SSS Example

Answer String: Enter the length in cells of each of the shaded segments (sunglasses, snake, and shapes) from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 16:00, Master = 22:00, Expert = 44:00

Solution: PDF; a solution video is also available here.

  • Jack Bross says:

    Terrific puzzle. I guess I’ll rot13 my favorite moment in case it counts as a spoiler:

    Gung pna’g or evtug orpnhfr V pna’g unir gjb j cragbzvabrf … hayrff … ab jnl…

  • Chris Green says:

    Fantastic puzzle with an excellent solve. Would love to see more of this type in future.

  • Nis Jørgensen says:

    Jack Bross wrote: “Gung pna’g or evtug orpnhfr V pna’g unir gjb j cragbzvabrf … hayrff … ab jnl…


    A very nice puzzle, and a good thing that i didn’t have to learn all those rules for a one-off.

  • edderiofer says:

    The rules as stated don’t actually seem to forbid multiple copies of the same shape. I unfortunately didn’t prove that there wasn’t another solution if multiple copies of the same shape were allowed.

  • Avatar photo drsudoku says:

    I added a further clarification since you all seem to want to stretch the rules wherever you can; shapes are used exactly once, as is typical for this puzzle style.

  • Nathan McDonald says:

    So many times got stuck, then after some frustration and scouring would find the next break in that would magically open up huge amounts of the puzzle. Took a while on this but very rewarding puzzle thoroughly enjoyed!

  • SS says:

    “Dang, I borked it.”
    “Dang, I borked it again.”
    “DANG, I BORKED IT AGA…. oh wait”

    I loved this giant puzzle and the whole Japan week. It piqued my interest in the Toketa series – really wish they were offered in e-book form. (I prefer e-books, as I have a tendency to bork!)

  • RWhelan says:

    I was surprised by how much I enjoyed this. When I first saw the puzzle description I thought it looked like a bit of a mess with so much going on at once. However I found it to work well in practice with a really enjoyable flow to the solve, both for this one and for the easier one earlier in the week. I definitely wouldn’t be disappointed to see more of these at some stage.

  • rob says:

    My favourite moment was when I realized “gung’f n I, abg gur fanxr”…

    Vg nccrnef gur chmmyr vf nyfb havdhr jvgu n frg bs 11 cragbzvabrf zvahf I.

  • JohnJBulten says:

    Jack’s observation is fun considering how early that pentomino was eliminated. Rob’s is also insightful. Beautiful conclusion, troping a more typical conclusion to a pentomino puzzle.

  • LorenR says:

    I should not admit this, but *really* helps to reread the full instructions again after solving SSS puzzle 1 days before this SSS puzzle 2. I forgot the diagonal no-touch rule for both shapes and snakes!

    Really loved the solve after I indeed reread the full instructions.

  • SS says:

    FYI – all Toketa books can now be purchased as e-books with Paypal!

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