Yajilin (Regional) by Murat Can Tonta
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Theme: Clue Symmetry and Logic
Author/Opus: This is the 91st puzzle from our contributing puzzlemaster Murat Can Tonta.
Rules: Variation of Yajilin. Blacken some white cells and then draw a single closed loop (without intersections or crossings) through all remaining white cells. Blackened cells cannot share an edge with each other. A number in a region indicates how many white cells must be blackened. Cells with number clues may be blackened.
Answer String: Enter the length in cells of the horizontal loop segments from left to right in the marked rows, starting at the top. If the loop only has vertical segments in the marked row, enter 0. Separate each row’s entry with a comma.
Time Standards (highlight to view): Grandmaster = 8:00, Master = 12:30, Expert = 25:00
Solution: PDF
Note: Follow this link for other variations of Yajilin and this link for classic Yajilin. If you are new to this puzzle type, here are our easiest Yajilin to get started on. More Yajilin puzzles can be found in The Art of Puzzles 2.
Loved this variant at first – then perhaps a bit less as I struggled in the second half before eventually limping to the finish. Still, I appreciate these variants, so I’ve marked it as a favourite. 🙂
Yes, this one had a very easy start, then threw in a lot of work to figure out the rest.
The solution path of this puzzle is absolutely beautiful! The level is also just-right in the way that it is not too hard enough to require guessing.
I agree with tamz29, the logic is beautiful. Amazing. For some reason I found the puzzle uncomfortable, though. As if the construction path had been very narrow, perhaps.
Some warmup puzzles might have made this one more attractive.
Thanks for the feedback everyone! I’ll readily admit that I intended this one to be difficult. I wanted a puzzle without too many small regions, which needed some tinkering to achieve. That familiarity might have caused me to think the solution path is less narrow than it actually is. I’d like to make more introductory puzzles of this variant, seems like those would be appreciated 🙂 Cheers!
I thoroughly enjoyed this puzzle. As others have suggested, I didn’t notice a point in the second half that requires a technique that’s unused in the first half, (but it’s a technique where a fairly simple observation unlocks a surprisingly large portion of the remaining puzzle).
I’m interested in seeing more examples of this variant, and may try constructing some of my own. (There’s something about puzzles that are presented with regions—like Star Battle and this variant—that appeal to me as a constructor).
+TomTom (and to a lesser extent Nanro); I feel the same way you do about how regions are a fun constraint to play with when designing puzzles.
I’m slow to the party … just seeing this puzzle about 7 months late. Unlike some solvers, I had to guess about 60% through. I saw some of the logic at that point which helped confine my guess, but still, a bit too tough for me to avoid the dreaded guess. I like the concept though. However, rather than “Yajilin (regional)”, I can’t help but think this puzzle should be called “Loopawake” … or maybe better, “Heyaloop”.
17:49.Happy to have made the expert time. .Amazing puzzle really.Solved it after seeing it in the best of the year series.I solved logically .My progress was basically by obtaining miniscule contradictions along the solve path.Truly cherishing puzzle !