Araf (Different Neighbors) by Serkan Yürekli
or solve online (using our beta test of Penpa-Edit tools with a composite mode for line/edge drawing.)
Theme: Rooms
Author/Opus: This is the 292nd puzzle from our managing editor Serkan Yürekli.
Rules: Standard Araf rules. Also, no two regions with the same size can share an edge. (Note: this is the same rule as in Fillomino puzzles where no equal size polyominoes can touch.)
Difficulty: 4.5 stars
Time Standards (highlight to view): Grandmaster = 9:15, Master = 16:00, Expert = 32:00
Solution: PDF; a solution video is also available here.
Note: Follow this link for more Araf puzzles on this website. If you are new to this puzzle type, here are our easiest Araf Puzzles to get started on. More Araf puzzles can be found in the ebook Araf by Serkan Yürekli.
Great puzzle, tough but with a very clean logical solving path. (The deduction where bar ynetr ertvba zhfg nibvq fcyvggvat gur pyhrf vagb gjb tebhcf bs bqq fvmr in particular was really sweet.) The different neighbours constraint is used very well; it keeps driving things throughout the solution. Thank you!
Very smooth solve. I’m not convinced that this is 4-and-a-half stars in difficulty, though; it felt significantly easier than the previous day’s Araf.
It’s kind of a tough thing to decide the right difficulty level for some puzzle types which attract solvers to use intuition rather than logic. You know, before sharing each puzzle with you, we are testing. First, we test uniqueness, and then share these puzzles with our authors to find the difficulty level. In the testing process, some authors might use intuition more than logic. Especially in this kind of puzzles. This may cause ambiguity about the puzzle difficulty level. Saturday puzzle mostly based on the logic way, but the Friday puzzle more suitable to be used intuition, and some authors tested it in this way. For example, my uniqueness testing times for both puzzles are nearly the same, because I needed to find the logical way to prove there is a one solution for both puzzles. However, if I’d solved these puzzles as a solver, probably my solving times would be shorter, at least for Friday puzzle. Because I would have solved it as what I saw, not what I thought. But, if you try to find the logical solving path for the Friday puzzle, you may feel like the Friday puzzle is harder than the Saturday puzzle.
It’s never been clear what these star ratings mean precisely, and unfortunately there’s nothing on the website to help clarify their meaning beyond a very vague and subjective proxy for difficulty.
If that’s the intention, then I find the star ratings mostly unhelpful, particularly as there are already time standards given if you really want a more precise idea about difficulty.
Amazing puzzle ! 30:55