Nerodia (Aquarium + Snake)
(Published on 28. February 2022, 21:48 by Nordy)
This puzzle is the result of a collaboration with my buddy Pokitchayng. He does not have an account here (yet), but you can find him on the CTC Discord.
Assignment #1: Welcome, new recruit! You have been assigned to an enclosure with our newest semi-aquatic snake, Mr. Slithers. This particular reptile has a knack for hiding—in fact, you will have to work out exactly where he is in the habitat. We have provided you with a blank diagram of the enclosure. Please notate the current water levels and use them to track the location of Mr. Slithers.
Rules: This puzzle combines aquarium and snake rules.
Aquarium:
- Each bordered region is an aquarium, and cells must be shaded blue (water) and green (air).
- Within a region, any cells that are in the same row must be the same color.
- When a row of cells within a region is filled with water, all cells below that row in the region must also be filled with water.
- Regions may be entirely water or entirely air.
Snake:
- Place circles in cells (or use another technique) to form a single 1-cell wide snake.
- The snake cannot touch itself orthogonally or diagonally.
- The two ends of the snake are marked by black circles.
- No set of 3 consecutive snake cells may be all water or all air. For example, if the snake passes through two water cells in a row, then the next cell on the snake’s path must be air (Mr. Slithers has to breathe!)
- Every region must contain at least two snake cells.
External Clues:
- Numbers outside the grid indicate the number of water cells and/or the number of snake cells in the corresponding row or column (a number can signify the amount of water cells, snake cells, or both).
Example: An example puzzle and solution are included for your reference. We found that Penpa+ with circles and lines for the snake was the most user-friendly.
Here is the main puzzle. Good luck!
- Penpa+ (Shade air cells green and draw a green line through the snake for answer check)
- CTC
- F-Puzzles
If you get stuck, rereading the rules can be helpful!
Solution code: Starting from the top row, the number of snake cells in each row (9 digits) followed by the number of water cells in each row (another 9 digits)
Comments
on 4. April 2022, 14:53 by thefallenrat
The hardest working snake on the grid!
on 2. March 2022, 16:31 by Luigi
What a fantastic puzzle!!
Thank you very much for sharing it with us!
on 2. March 2022, 14:18 by DVFrank
Very nice! :^)
on 2. March 2022, 07:59 by Statistica
Sehr hübsch. Danke!
on 1. March 2022, 19:30 by Dandelo
The old discussion about "snakes and loops touching itself" ...
In the forum you find a long discussion (in German, but Google translator will help).
http://forum.logic-masters.de/showthread.php?tid=943
on 1. March 2022, 14:37 by SudokuExplorer
Btw, the example puzzle is not unique: https://tinyurl.com/n9z9xvsr
—Nordy: Ah, perhaps the “path” tag is confusing here? The path in this puzzle has to behave like a traditional snake (not like the loop in a castle puzzle, for example). The solution you provided is a snake that “touches itself”. I am now very intrigued about an aquarium puzzle with that type of pathing now though…
SE: I completely forgot about the snake rules, but could still make quite a few interesting deductions in the example puzzle. I'm glad my failure to understand all the rules has actually inspired you to think about another puzzle. I look forward to it! :-)
on 1. March 2022, 02:59 by Nordy
Minor formatting fix
on 28. February 2022, 22:50 by Jesper
Good fun, thanks!
