I'm very grateful to LMI for providing me the opportunity to author my own PR round this year. I was very excited about the project, but unfortunately in March I contracted COVID-19, had quite severe illness, and I still have not mostly recovered from it. Unable to progress with the puzzles, I was lucky enough to get help from Prasanna to complete the round. We have put this round together (with a lot of last minute work from him), hoping you guys like it!
I am sorry for the troubles caused, and very thankful to Prasanna for making it happen finally.
All the best for the round, stay safe, and take care, you guys! Lots of love!

The Dosun-Fuwari example had 2 solutions. It should be fixed now, IB re-uploaded.

Note: Pending solution booklets (R1, R2, R4) have all been linked to in their respective discussion threads. Just thought I'd mention here since people are likely to see it. Apologies for the delay with posting them.

I think that the instructions in Dosun-Fuwari Park need some clarification. As it's written, I don't see a conflict between the solution given and the solution that would happen if the bottom-right-most black L would move 2 upwards. Every shape would have at least one ball above another iron ball.

The statement that each room contains one balloon and one iron ball is also concerning, as the solution shows 3 balls and 4 balloons per region.

Perhaps something along the lines of "groups of iron balls" and "groups of balloons" could be implemented--each room contains one group of balloons and one group of iron balls. And then something like: At least one cell of the group/shape is immediately under black cells, other balloon groups, or the upper grid border.

I understand the intent of the rules, having seen similar puzzles before, but can sense a lot of potential petitions with the instructions as written.

The first sentence of the rules describes balloons as "white circle shapes" and balls as "black circle shapes". The 'shapes' bit is underlined to show that that description of balloons and balls is different from regular Dosun-Fuwari. I am open to suggestions to make it clearer but I want to know if this addresses your concern, and if not, why it doesn't.

10 ~ 12. Myopia (Shapes)
I found better name 'Polytopia', which is appeared on Swiss WPC Qual 2017.
https://logic-masters.de/Wettbewerbe/CE/wettbewerb.php?chlang=en&id=...

or what about Polypia? (I confused Loop puzzle category...)

Edited by Joo M.Y 2021-04-28 4:10 PM

I agree with the rest of your post, concerning the overall fairly confusing language in these instructions (but overall it's just barely clear enough that I got it right and was able to confirm using the example). But regarding what happens if you move the bottom-right-most black L shape upwards by 2, then this isn't a valid solution anymore, since the other black L shape that is currently resting on it would no longer be supported -- none of its iron balls is supported if you remove the black ball in R6C5.Since we're complaining about this puzzle, I must say my main concern about confusing rules is that this one doesn't allow white and black to touch, while the basic puzzle Dosun-Fuwari allows them to touch... and my biggest concern about both types overall is that the coding of solutions by 012 seems poorly designed. - for empty, o for balloon, * for ball would be more logical / easier to remember. Or - ^ v (things that go up and things that go down). Oh well. 012 it is.

Edited by auroux 2021-04-29 9:35 PM

I was under the impression earlier that the "iron ball" identified an individual circle, instead of the entire shape. Under that, I saw that any of those entire shapes in the example puzzle could be "unsupported". As such, one of the individual circles here would be directly above another individual circle (in the same linked collection) and I didn't see how the ruleset precluded that.

It has since been made clear to me that the "iron ball" is intended to be the entirety of the linked dark circles, as the "balloon" is intended to be the entirety of the linked light circles. But that's where I was coming from with that observation.

Edited by Timjamiller 2021-04-29 11:40 PM

Re: Alternate keys, I just figured 012 are closest together on a keyboard :) For me that would be easiest but I take your point. I don't want to mess with the system changing things right now. I'll keep it in mind if I see a puzzle like this in the future.

I think there's a small ambiguity in puzzle 18.

Thank you for pointing this out. Since it doesn't affect the key we thought the fairest option is to announce it on the submission page and leave it as is. Apologies for the inconvenience (also to future solvers).

In the Dosun-Fuwari Park example in the IB, would it be a valid solution if the balloons in the solution in cells B2:E2 (Excel notation) were instead moved to B2:B5?

Sstackho:
In that case the balloon shares an edge with the ball piece in B6 which is not allowed.

Sorry, I removed part of your post because I was experimenting with the restrict-thread thing (It wasn't working properly)

I am so happy that I finally managed to finish all puzzles in a PR episode :). Much thanks to all the people who made my puzzling fun possible.

Not too difficult but very nice set of puzzles! It‘s probably the first time I finished all puzzles in time in a PR round, and that on my birthday :). Thank you!

Edited by ropeko 2021-05-01 3:08 PM

Wonderfully balanced set of puzzles. Had a lot of fun. Glad I could finish it just on time but disappointed that I wasted lots of time imagining the rotations and reflections of "5" shape.
Enjoyed thoroughly. Thanks Priyam and Prasanna, testers and LMI :)
I liked all the high-pointers.

Uh...the link at the top is contradictory at the moment. It says this goes until May 5th, but also says it ends within 24 hours right now. I think that ought to be resolved.

Ya fixed that now, thanks.

Hi All, just one "patological" note for Dosun-Fuwari Park puzzle.
Reading the rules, if I have an Iron-ball shaped as the U pentominoes, I could have, in theory, two such iron-ball linked togheter "floating" supporting each other with no other "support" below them. The same for two U-shaped baloons.

OO
OXX
OOX
XX

I guess that, in the "spirit" of the rules, it will be not allowed, but in theory it could be a valid solution with the actual rules ... :-)

Obviously, other shape could have the same effects.

By
Gabriele

Fantastic set of puzzles, better than some of the previous rounds this year. They were very approachable and had pleasant solving paths.

Favourites:
15 - Statue Park
20 - Stargazing
11 - Myopia Shapes

Thanks a lot Priyam and Prasanna!