Draw rectangular loops through the center of some cells. Rings may only intersect only perpendicularly at their sides; they do not overlap or share corners. All white cells must be connected to a loop and all black cells must not be. Loops cannot pass through dotted fences.
For the purpose of this puzzle, a "rectangular loop" can move from one side of the cube to another, as long as it is continuous and made of only interior right angles. Play this puzzle on Penpa+
Thank you so much everyone who tested this puzzle! And shoutouts to jovi_al for introducing me to ring-ring puzzles, and everyone else who participated in zetamath's pencil puzzle challenge :)
Solution code: the solution code is formatted A-B-C-D, where A, B, C, and D count the number of (2D) tiles taken up by any rings that are on the marked cells
on 14. March 2024, 22:33 by MicroStudy
bananaphone
on 9. October 2023, 13:46 by zzw
Super cool little puzzle, lots of fun! Makes me want to combine more puzzle types with this sort of grid...
on 15. January 2023, 02:22 by wooferzfg
Really fun, thanks!
In this puzzle, a rectangle can have 3 corners :)
on 16. November 2022, 20:17 by KNT
lovely stuff, thanks wisty :)
on 14. November 2022, 06:32 by Wessel Strijkstra
Greatly enjoyed, interesting and very fun :D
on 12. November 2022, 22:05 by dumediat
I can’t recommend this puzzle highly enough, such a joy to solve with some really surprising logic!
on 12. November 2022, 21:41 by virtual
Lovely extension of Ring-ring to a 3D surface!
on 12. November 2022, 21:39 by jovi_al
:)