Rules:
U-Bahn: 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, or turn) appears in the corresponding row or column, irrespective of the line shape's rotation.
Empty Cells: Each row and column has exactly one empty cell which isn't visited by the loop network.
Puzzle Links: You can solve the puzzle in either Penpa+ or in CTC software.
Solution code: For each column from left to right except to last, the number of lines leading right from that column.
on 21. September 2024, 00:43 by zetamath
This ruleset really plays to the strengths of ubahn, that of knowing "this looks kinda like this" in a way you can't possibly notate but the deductions flow together in a good way when you don't miscount like I did on my first attempt.
on 30. June 2024, 12:44 by AnnaTh
Wow! That was pretty hard (for me). But very satisfying! Can't wait for your next U-Bahn-puzzles:-)))
on 29. June 2024, 21:48 by wooferzfg
Really nice, thanks!
on 29. June 2024, 18:05 by Agent
Great fun! Should be a smooth solve if I wasn't blind.
on 29. June 2024, 14:51 by Jesper
Very nice, thanks!
on 29. June 2024, 13:55 by Piatato
Awesome first U-Bahn! Really crisp and tasty logic all the way to the very end :D
on 28. June 2024, 22:35 by ONeill
Amazing, very satisfying to figure out, thanks!
on 28. June 2024, 21:24 by KNT
great first u-bahn :-) now we wait for the second...