Logic Masters Deutschland e.V.

Yin-yang Sudoku

(Published on 28. December 2022, 12:40 by Prutsbeest)

This puzzle is a Yin-Yang puzzle, but also an 8x8 Sudoku:

Yin-yang rules:

Shade some cells in the grid such that the following conditions are fulfilled:

- All shaded cells are edge-connected to each other.

- All unshaded cells are edge-connected to each other.

- No 2x2 area is fully shaded or fully unshaded.

Sudoku rules:

Fill the grid with the digits 1-8 such that:

- Each row contains the digits 1-8 exactly once

- Each column contains the digits 1-8 exactly once

- Each region contains the digits 1-8 exactly once

Two of the digits 1-8 from the Sudoku have special meaning: they represent the number of shaded cells surrounding that digit (including the shading of the cell itself). Those two digits need to be determined by the solver.

For example, if the digits 3 and 6 are the two special digits, all the 3's in the finished Sudoku have to be surrounded by exactly 3 shaded cells, and all of the 6'es in the finished Sudoku have to be surrounded by exactly 6 shaded cells.

The example below should clarify this: it shows a 2, 3, 4 and 6 which are surrounded by 2, 3, 4 and 6 shaded cells respectively.

Finally, in the overall puzzle, the total sum of the digits in the shaded cells should be lower than the total sum of the digits in the unshaded cells.

And then for the actual puzzle:

F-puzzles link: https://f-puzzles.com/?id=2kb7dhe4

Have fun solving!

Solution code: Row 5 of the Sudoku followed by column 6 of the Sudoku (16 digits, no spaces)

Last changed on on 28. December 2022, 14:41

Solved by sinchai4547, filuta
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Comments

on 1. March 2023, 14:09 by filuta
oh, I finally got it, thanks for the push in the right direction (which embarrassingly was at almost the easier step of the puzzle :o)). absolutely great take on YY but a very hard puzzle for me as well

Difficulty:4
Rating:N/A
Solved:2 times
Observed:7 times
ID:000CFZ

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