SOKOBAN

@anian I got it, thanks a lot! It's very clear now

@wedge Sent you the emails.

@anian yeah for 917 I missed the deadlock part, it's so small. My email is zamsh7@gmail.com if you can send the images please

@wedge I meant to say "For 917, you cannot even push any box to any goal without deadlock". The tiny "not" makes all the difference. I wish we can delete or edit our own messages here.

@wedge For 917, you can even push any box to any goal without deadlock. So, it should be obvious that it is an unsolvable level. For 916, 918 and 4136, if you play the level in reverse mode, you cannot pull open the level. You will first need a Sokoban program that can play in reverse mode. There are a few Sokoban program out there that can do that. For example, YASC, Boxman for Android, Boxman for Windows, Sokoplayer HTML5, SokoFan. If this site allows posting images, it makes it easier to explain. Or if you provide an email, I can explain more in an email with images.

oh sorry, I overlooked a simple thing in 917. It is indeed very easy that it is impossible. Also 4136. For 916 and 918 it is not clear to me that they are impossible and it is matter of the size of the free space and the number of boxes

@anian I wrote a script, and the way it works does not take into account anonymous solutions. It was not really intentional, but I never cared much about it. I know how to export levels, just didn't know the format was called XSB. I see what you mean by reverse mode and I believe you that 916 918 are impossible but why is it "very easy" to see? For 917 I don't even see why it is not possible. Can you please elaborate? Also updated 4768 as solvable in my records

@wedge For 4768, I just submitted an unoptimized solution.

@wedge XSB format is the most popular Sokoban level format. Any good Sokoban program nowadays will support export and import of XSB format. On this site, open any level, near the bottom-right corner there is a "?" mark button. Click on that, it pops up a panel. In the code section, those text are XSB format of the same level. As for 916, 917, 918 and 4136, it is very easy to see that they are unsolvable using reverse mode. In reverse mode, you cannot pull open these levels. That just means, in normal play mode, you cannot fill all those goals. Thus unsolvable. I don't know why you would ignore anonymous (anonimous) solutions. They are also solutions submitted by someone. The only difference is that they didn't login to the site when the level is solved.

@Mr.Kem yeah I might have sent it sometime ago . For reference, this is the list of the S shaped levels, but they are harmless as Mr.Kem said: [1] 2026 8770 9550 9680 9737 9744 9794 9831 9840 9912 9915 9918 9941 10635 10648 10688 10735 10740 10778 10796 10798 10809 10811 10813 10825 11296 11306 11307 11350 11430 11449 11455 11457 11602 11676 11677 11681 11800 11858 11866 11873 11874 11885 12184 12217 12259 12276 12379 12731 12736 12784 12837 12898 12901 12902 13246 13322 13340 13501 14150 14193 14239 14241 14242 14244 14312 14406 14459 14698 15530 15635 15818 15939 15950 15983 16022 16974 16975 16984 19263 19323 19331 19341 19343 19350 19351 19352 19355 19727 19733 19742 19743 19744 19747 19753 19763 19765 19767 19802 19827 20465 20600 20601 20610 20615 20620 20626 20627 20628 20632 21457 24231 33020 33078 33112 33741 35774 35987 36479 37347 38068 38231 38249 38252 38257 38265 38268 38979 38980 38984 38987 38990 38992 39137 39640 40253 40298 40301 40319 40731 41532