Logic Masters Deutschland e.V.

U-Bahn with Empty Clues (4)

(Published on 28. July 2023, 15:50 by KNT)

Draw a totally connected loop network through the centers of some cells, which may branch or turn, but may not have any dead ends.

A clue outside the grid indicates how many times the corresponding line shape (i.e. a cross, branch, straight line, turn, or empty cell) appears in the corresponding row or column, irrespective of the line shape's rotation.

The letters A through E replace unique numbers. A question mark can be any number as long as it is not the same as any number replaced by a letter.

SudokuPad

penpa+

Solution code: For each column besides the last, the number of lines leading right from that column

Last changed on on 24. June 2024, 00:31

Solved by wooferzfg, Jakhob, polar, Piatato, Koalagator2, ONeill, Myxo, jkuo7, Bellsita, zuzanina, Zzzyxas, lupo, chalk235, laregioncentrale, pkp, wand, Agent, Niverio, ibag, pandiani42, Jesper, Gliperal, wisty, akamchinjir, Vebby, The Book Wyrm, CJK, Nick Smirnov, Paletron, Mr_tn
Full list

Comments

on 20. March 2024, 18:02 by The Book Wyrm
Incredible puzzle.
Took me a while, especially because I broke it a couple times at the start due to overlooking options. Very hard deductions all the way through; even at the end, you have to work for very single deduction (I did, at least).
Lots of very interesting and complex logic thoughout. Extremely impressive puzzle.

The logic surrounding the ? clues, and how the were able to resolve stuff despite the only restrictions on them being a few numbers they couldn't be was very interesting. Really liked that.

Thanks for the puzzle!

on 6. November 2023, 05:12 by wisty
Holy cow, that was long. Great puzzle! Really fun and memorable first half, followed by an intricate and jaw-droppingly thorough examination of the genre in the second half. I absolutely loved it, but it was also probably the most time I've spent on a puzzle so far since picking up this hobby. There are definitely a couple spots that I suspect I over-complicated though. I'm the type of solver who really enjoys doing so anyway, since I feel I unlocked a full understanding of what the clues are doing, but I'm certain there is a very clean (albeit narrow) solve path overall. KNT, take a bow!

on 18. October 2023, 07:54 by Gliperal
Diabolical.

on 29. September 2023, 21:31 by Jesper
An epic puzzle!

I got properly stuck on my first attempt, but this time, thankfully, I spotted the deduction that evaded me last time :)

on 14. September 2023, 15:24 by ibag
Finally! I can't remember the last time it took me so long to solve one single puzzle. Great!

on 9. September 2023, 00:37 by Niverio
Absolute insanity, why would anyone even set this puzzle, do they want their solvers to die

on 2. September 2023, 02:27 by Agent
Wonderful puzzle! The solution path was utterly relentless, but equally rewarding. A beautiful proof that U-Bahn logic can be extremely rich (and also extremely hard).

on 2. September 2023, 00:46 by wand
a wild journey. stuck for nearly all of august in the middle before inspiration from other u-bahns and wooferzfg's tutorial struck. really enjoyed it!

on 23. August 2023, 23:09 by chalk235
Beautiful puzzle! I needed to read wooferzfg’s ubahn document a few times to have any chance of solving this. Doing this puzzle felt a bit ike reading Lord of the Rings for the first time - both thrilling and exhausting!

on 19. August 2023, 11:56 by lupo
Wow :-)

on 31. July 2023, 20:20 by KNT
@Luigi: No information is given in hint fields with no symbol (letter or ?). But no given ? may have any of the values you have deduced.

on 29. July 2023, 22:49 by Myxo
Awesome, really challenging puzzle!

on 29. July 2023, 19:57 by ONeill
Very nice and difficult :) A lot of the deductions were new territory for me. Thanks!

on 29. July 2023, 06:30 by Koalagator2
Brutally difficult puzzle although part of that is due to my inexperience with U-Bahn. Overall, very fun.

on 29. July 2023, 05:42 by Piatato
I greatly enjoyed the first 30 minutes, which went very smoothly for me. Then I was thoroughly schooled for the next 10 hours. In the end my brain was brutalized so horribly that I spent two hours on the relatively easy last deduction. I hope that I'll recover, so that I can use the things I have learned. Tremendous puzzle!

on 28. July 2023, 22:49 by wooferzfg
@Koalagator2 Yes to both questions: The values of the ?s cannot be any of A-E, and A-E are all different numbers (not digits, so they're allowed to be more than 9)

on 28. July 2023, 18:09 by polar
Awesome puzzle, thanks!

on 28. July 2023, 17:11 by wooferzfg
Solving this was a really challenging and very fun experience, which tested every corner of my U-Bahn knowledge.

Difficulty:5
Rating:99 %
Solved:30 times
Observed:2 times
ID:000EMR

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Solution code:

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