Why?

It could be a number of things: printer differences, a difference in personal preference, maybe one of us is using a darker pen/pencil than the other (I used HB pencil). It's difficult to please everyone :) Next time I'll know to bring a pen or a darker pencil.

It's interesting you pointed that out. I'm using pen (blue), which is really well visible when I write something down. Cannot agree more that this is probably the reason why nothing is too dark for me. Pencil is something I just don't like using.
I also agree that there might be printer issues, although I haven't configured any settings there. Just printers are different.

But really it was better this time. You (organizers) already have done something for of me and I really appreciate it. I also don't want to say that I would have done 5 minutes faster if the gray was darker. No, I'm talking about some seconds here which probably didn't affect my result.

The fair thing would be to keep everything more or less similar than this time.

@TiiT @Feadoor
Thanks for your feedback regarding the shades. One thing we can probably do in the future for coded/substitution alphabets is to provide in the top left corner in black color (similar to True or Lie), this will keep the centre space empty and also make alphabets clearly visible. In regards to shading, we hope the below test will help to further improve.

@Everyone - If you don't mind, can you please print the following puzzle and share your feedback regarding which shade you feel is very light, very dark or appropriate/suitable. That would help us to further improve the choice of color.
Thanks in advance to all.
https://git.io/Jmd7K (Use "Screenshot" button at the top to download the image with default settings as is (i.e. High Quality and PNG))
You can either share your feedback here or send it to penpaplus@gmail.com, your time is very much appreciated.

Edit: Added alphabets to each shade and option for easier reference and feedback.

Edited by swaroop2011 2021-03-22 12:18 AM

For me, it would break down into the following:

Shaded
Ideal - C
Workable - B,D,K
Too dark - A,S

Thermo
Ideal - E
Workable - F,G
Too dark - H,I,J

Line
Ideal - R
Workable - L,M,Q
Too dark - N,O,P

Arrow
Ideal - U
Workable - T,V
Too dark - W,X

What seems to work best for me is as light as possible (since the shapes are large enough to be distinctive), except for lines perhaps take 1 shade darker than the very lightest since they can be easier to miss. But honestly anything within the workable range is perfectly fine for me

Edit: Standard printer settings, wrote some pencil marks and digits in each cell with a regular HB pencil. I also want to add that I think moving coding information etc to the cell corner is a great idea

Edited by bakpao 2021-03-22 6:40 AM

Sir, I did not expect that SM-3 round would be easy because generally your genius sudokus and puzzles are tough and require more time to solve but in this round all were easy. My favourites in this round were 9x9 Fortress Sudoku and 9x9 Consecutive Pairs Sudoku.

What an interesting contest. My laptop gave trouble so I got stressed out and lost my focus.in general I get a little demoralised when contests are very tough, Thus has brought back my confidence and enthusiasm in solving contests. Thanks very much Mr, Rakesh for a very enjoyable SM. I wish my score proved it.

Fantastic set. Didn't expect anything lesser.
Great example of how easy sudokus can be of high quality.

Favourites:
True or Lie 6x6
Consecutive Pairs 9x9
True or Lie 9x9

Thanks Rakesh!

As Dhruv had earlier mentioned, I too was surprised by the much easier set. I started the set remembering Rakesh's mean mini set. But found easier and so made an error in 9×9 Fortress which ate my time. Eventhough I didn't finish the set, this was my best effort in SM and a BIG thankyou for that Rakesh.

Very apt password.
My favourite was the 9×9 Fortress and the True or Lie

For me the best shading is:

Shaded - C, K
Thermo - E, F
Line - Q, R
Arrow - U, V

Shading A is not usable for me at all.

Thank you for asking this feedback.

I have to be honest. I printed it out and basically everything is workable (with only few exceptions). If you have used some of these in competitions, then there must me something else, which affects this (maybe the quality of pdf file, the pdf itself or resolution).

I first recommend to create an actual pdf and not put these different variants next to each other. Like this C feels fine only because it has darker areas on it's sides.

So:
Shaded:
C - Cannot tell for sure, it seems fine, but maybe a bit too light.
K, D - Perfect for me
B, S - workable
A - A bit too much

Thermo:
E - Would say workable, but not sure
F, G, H - totally fine
I, J - workable

Line:
L - workable in here
R, Q - Perfect for me
M, N, O - workable
P - maybe too much, but would be workable for me

Arrow:
U - seems workable
V, T - perfect
W, X - Also totally fine

numbers 1 and 2. I can see them clearly in here. They are definitely not the same as they were in coded sudoku. In here both are fine.

Great set of Sudokus, relatively on the easier side. I echo Tiit's views that the Fortress was too dark and the Coded alphabets were too large, which made the solve slightly uncomfortable. I also found the True or Lie 9x9 to be tougher than the Fortress 9x9, though it was worth lesser.

Overall, a fantastic set. Thanks Rakesh!

What a Great set of Sudokus! Loved all of them. I had some issues with reading the numbers in coded Sudokus(penpa), But didn't have much problem as they were not hard to solve. Consecutive pairs Sudoku 9x9 increased my time by a large margin.
Amazing set. Expected nothing less from you sir. Thank you

A very enjoyable set of sudokus. My favourites were consecutive pairs 9x9 , Fortress 9x9 and consecutive pairs 6x6. Classics were enjoyable as well

Enjoyable set of sudokus. I just quickly saw the variants in a hurried rush before taking the test. After finishing it at a stroll, I remembered to check who the author was, and had to do a double take after seeing it was Rakesh, never would have expected this level of difficulty from him :)
Favourites were Consecutive Pairs 1 and 2, and Classic 3. Thank you, Rakesh.

Thanks Tiit! Perhaps True or Lie was slightly undervalued in terms of points, as noted by Aashay too.

Thanks Dhruva!

I also wish the score would have been better. But we cannot control external factors. Hope to see you do better in the next round.

Thanks Rohan!

Congratulations for your best effort. I was hoping for a century too. Personally, I think rank is more important than absolute score. I hope this would be one of your better ranks too!

Glad that you noticed and mentioned it (the password).

Thanks Aashay! Agree with your points on Fortress and Coded. True or Lie may indeed have been trickier. One of the reasons it had lesser points is that it had less variant part and was almost a classic/pencilmarks sudoku.
Thanks Nityant! Consecutive pairs 9x9 was a straightforward solve (unless you unnecessarily bring the converse rules into play)

Thanks Akash! Not surprising as Consecutive Pairs is one of your favourite variants as I can see on your blog.

Thanks Pranav! You were the co-author of this round last year. So I guess these variants would be familiar to you anyway.

Thanks to the 357 participants.

Congratulations to Tantan Dai, Seungjae Kwak, Tiit Vunk, Jakub Ondrousek and Kota Morinishi for taking the top 5 spots - finishing in less than 36 minutes.

Also, Congratulations to Prasanna Seshadri, Rohan Rao and Kishore Kumar for taking the top 3 spots from India - finishing in less than 50 minutes.

A high number of finishers in this round- 125 overall, and 21 from India.

Thanks to Rakesh Rai for authoring this round!

The Solutions Booklet is now available.

Those who missed taking part in this test can still take this test unofficially.

Wonderful contest. Thanks Rakesh and testers and LMI.
Feels Good to finish an SM round.

Fun filled and well balanced set for SM. Favorites were True-Lie-2 and Fortress-2. Thanks Rakesh!

Thanks Swaroop!

Thanks Harmeet! I think this set was not that "balanced" as all sudokus were on the easier side (except maybe some classics)

I am glad this round did take place as per the schedule. Thanks everyone who took part, and everyone who posted their feedback!

I tried to keep the sudokus "not difficult" in this round. And we have a record number of finishers this time! Happy to see 21 finishers from India.

Personally I would have liked to make some of the sudokus more elegant - less clues in renban 9x9, more "true or lie" clues in True or Lie 9x9 and lesser shaded clues in fortress 9x9. Coded and Consecutive Pairs were exactly as I had planned. For Coded, I came up with the "The charm of March" initially and luckily got a neat "Home craft" from these letters. This helped to make the decoding part very easy. (Pleasantly) Surprised to see many "pure" sudoku players attempt and solve coded sudoku in this contest.

Nice to see Kartik, Shambo, Harsh, Poonam, James Peter, Dhruva, Nityant and Harmeet in the 100s! Congratulations all!
And a very impressive timing from Tantan - significantly ahead of everyone else. Congratulations!

Looking forward to the next round - Math.

My opinion on the grayscale benchmark, although I never had a real problem in a competition with this :

Shaded
Ideal - K
Workable - C,D
Too dark - B,S
Impossible to see my writing : A

Thermo
Ideal - F
Workable - E,G
Too dark - H,I
Impossible to see my writing : J

Line
Ideal - M,Q
Workable - N,O
Too light/dark - L,P,R

Arrow
Ideal - U
Workable - T,V,X
Too dark - W


I think overall, I prefer lines (and arrows) darker than shading/thermo.
Also for clues (like coded), I'd rather they were small and in a corner rather than big and center (it also gives the advantage of printing them black instead of grey).