Double or Nothing Roller Coaster
(Published on 16. July 2024, 16:31 by KNT)
Draw a loop that travels orthogonally between the centers of some cells in the grid. The loop may cross itself, but wherever it crosses, both ends must travel straight; a cross is never two right angles touching.
Clues to the left of rows indicate the sum of numbers on horizontal segments of the loop in that row, in the correct order. Clues above columns indicate the sum of numbers on vertical segments of the loop in that column, in the correct order. A question mark may replace any number from 0 to 9, but no clue may have a leading zero.
A number on a cross either counts as double its value, or as 0, for all sums that number contributes to. That is, a number must not simultaneously contribute double its value towards a column clue while contributing 0 towards a row clue, or vice versa.
A 1-7 example is provided:
Solution code: Row 7, Column 9
Comments
on 20. March 2025, 18:27 by wullemuus
Almost "easy" once you got used to the additional rules. The example puzzle really helped to get familiar with the logic. Such a smooth (and therefore brilliant) solving path!
on 19. July 2024, 15:32 by ibag
A true masterpiece (as so often).
on 18. July 2024, 16:35 by MaizeGator
Very challenging (5*) for me, but in a good way. The possibility of the loop crossing played with my mind, while the arithmetic of doublers or zeroes was fascinating.
on 18. July 2024, 08:22 by Jesper
Great puzzle, well crafted solution path, thanks!
on 17. July 2024, 14:45 by ONeill
Fun rollercoaster twist. Definitely need to double check your deductions in this one :)
on 17. July 2024, 14:05 by MagnusJosefsson
Fantastic! A variety of interesting and clever logic with quite consistent difficulty throughout.
on 17. July 2024, 13:30 by Piatato
Awesome puzzle, very interesting and fun throughout, thanks!
on 16. July 2024, 20:00 by Christounet
Not nearly as brutal as the deconstruction we made with those double crossers, but still...
Enjoyed the addition of the "nothing" rule here. New layer of logic and adds an interesting ambiguity to the japanese sums. Thanks :)
