Logic Masters Deutschland e.V.

Snake Sweeper Redux

(Published on 3. August 2020, 13:26 by glum_hippo)

I have revisited the 'Snake Sweeper' idea, but with a completely new puzzle and a considerably streamlined rule set compared to puzzle 0003MZ, which was released here on June 13, 2020.

This is a combination of Snake, Minesweeper, Pentominous, and partial Killer Sudoku. Standard Snake and Sudoku Rules apply. There is a 35-cell snake in the grid which begins in the corner cell R1C1 and visits each box at least once, without ever touching itself, not even diagonally. In the snake, each linear pentomino (I, L, N, U, V, W, Z, colored yellow) is used exactly once.

The 13 blue cells already in the grid are 'Snake Sweeper' cells, and they each contain a digit between 1 and 7. No digit appears more than twice, i.e., all but one of the digits 1-7 are used twice. These digits both act as Sudoku givens and they give the total number of snake cells in their diagonally/orthogonally surrounding cells (compare the classic PC game 'Minesweeper').

The snake must leave room for exactly one each of the P, F, and Y pentominoes (colored grey). These three pentominoes must touch but not overlap the snake. They may also touch each other. Once these are correctly placed and oriented, they also contain blue cells with accurate Snake Sweeper values that act as Sudoku givens. The grey cells may or may not be correct.

No pentominoes overlap the blue cells already in the grid. Also, pentominoes may be freely rotated or reflected.

Once the 10 pentominoes are placed (T and X are not used), they act as cages, and it is a fairly straightforward partial killer Sudoku, which, during the solving process, will also disambiguate some of the pentomino positions. Cage sums are given for some of the pentominoes, and no cage may contain a repeated digit.

Example (with Tetrominos)Solution

The puzzle can be accessed on Penpa. To use the built-in answer checker, use 'Line' for the snake; dark grey 'Shading' for the P,Y, and F pentominos; and green or blue 'Number's for the Sudoku digits.

Solution code: For row 6, enter the pentomino type for all cells (or 0 [zero] for cells without pentomino), followed by all the sudoku digits. Do the same for column 3. For the example puzzle, row 2 and column 3, you would write: LLLS00 234561 0L00I0 146523

Last changed on on 20. September 2021, 18:01

Solved by stefliew, MumboJumbo, MagnusJosefsson, Queteimp, Jesper, NikolaZ, ffricke, Vebby, ildiko, SirWoezel
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Comments

on 24. August 2021, 10:50 by ffricke
Und auch dieses Rätsel ist wunderschön logisch zu lösen und verdient weitaus mehr Löser.

on 17. June 2021, 22:39 by glum_hippo
eingebauter Lösungs-Checker

on 5. August 2020, 12:07 by MagnusJosefsson
Wonderful puzzle! Definitely deserves a lot more attention. The snake/pentomino part is certainly very challenging, but I found the solution path for that part very nice and rewarding. So please, more people try this puzzle -- it's beautiful!

Last changed on 10. August 2020, 13:54

on 3. August 2020, 13:28 by glum_hippo
Vielen Dank an @stefliew fürs testen. In einer ursprünglichen Fassung wurde die Anfangsecke nicht angegeben, und ich bin weiterhin überzeugt, dass diese logisch erfaßbar ist, aber auch wenn das stimmt ist das Ausschlußverfahren einfach zu mühsam. Daher wurde der Anfang in R1S1 preisgegeben.

Difficulty:4
Rating:N/A
Solved:10 times
Observed:7 times
ID:000406

Puzzle combination Puzzle variant New Online solving tool Pentominoes

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Solution code:

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