Some puzzles for your solving pleasure

[Feadoor]

Hi everyone,

During my enforced isolation from the world, I have taken advantage of some extra spare time to produce a set of Sudoku puzzles very loosely inspired by current events. I hope you enjoy solving them, if you also find yourself with some spare time. Some of them are quite difficult.

Sam

[detuned]

Excellent to see more Latex use How are you drawing up the puzzles though Sam? At a guess they look like png files from (possibly Excel) screenshots?

[Feadoor]

Yep - they're screenshotted PNGs from my online tool for creating Sudoku puzzles (the same one used by Cracking the Cryptic). I thought about learning to use either TikZ or something like Inkscape, but I didn't have that much spare time.

[Puzzle_Maestro]

Thanks for the puzzles Sam! Just started working through them: the second has a very neat break-in.

Since school is closed for the foreseeable future, I may start producing some puzzles again...

[david mcneill]

Sam, thanks for putting these puzzles together. I haven't tried them yet but they look fantastic.

Do you think that we could all collectively think about publishing daily puzzles or weekly puzzle sets? Or monthly competitions?

Or is Cracking the Cryptic already doing enough?

[Puzzle_Maestro]

Something akin to the Japanese Heads Up puzzle league would be pretty cool, I think.

[mwhite]

Thanks so much for these. Haven't looked at them yet, but looking forward to having a go. I found both your WPC and UKPA Open rounds very challenging but fun, so more chances to try some of your sudokus is very much appreciated!

[detuned]

Something akin to the Japanese Heads Up puzzle league would be pretty cool, I think.

Could you give a brief summary of what that is and how it works? I’ve never heard of that

[Puzzle_Maestro]

Recordings of the league can be found at Ken Endo's YouTube channel: https://www.youtube.com/channel/UCVhOlV ... r_FWpt6FbA

It's essentially a competition where players go head to head against each other in matches (similar to the WSPC playoffs), and a different person creates the puzzles each time. It's probably pointless to emulate this as I don't think we'd have the resources, but we could have some sort of competition every once in a while.

[detuned]

Interesting... those puzzles are live here:

instruction https://drive.google.com/file/d/11OayiF ... sp=sharing
SetA https://drive.google.com/file/d/1EHuDeD ... sp=sharing
SetB https://drive.google.com/file/d/1bwYQq7 ... sp=sharing
SetC https://drive.google.com/file/d/1cjNg5L ... sp=sharing
SetD https://drive.google.com/file/d/1wtlQlu ... sp=sharing
SetE https://drive.google.com/file/d/10GEBaL ... sp=sharing
SetF https://drive.google.com/file/d/1qbVj4w ... sp=sharing
SetG https://drive.google.com/file/d/1Nx3YJv ... sp=sharing

[Feadoor]

I'm back with some more puzzles. These are, I think, all quite difficult. Nonetheless, they are all logically solvable. Have fun!

[Puzzle_Maestro]

Thanks for another sudoku pack Sam! Looking forward to trying out the puzzles.

[detuned]

The killer from the second popped up on cracking the cryptic, and it did seem kind of familiar. If you enjoyed that one from Sam I suspect you'll also like the killer on the 2019 UKSC

[david mcneill]

I think the larger Group Sums appeared on CtC as well. Lovely puzzles, Sam. I took my time and solved them all logically. May not have spotted all the tricks, but very good fun during lockdown.

[detuned]

Thanks for the puzzles Sam! Just started working through them: the second has a very neat break-in.

Since school is closed for the foreseeable future, I may start producing some puzzles again...

I think I might have missed this neat break-in. After a lot of staring at it, I did a short bit of trial and error to determine the extra regions area (which I'd already narrowed down to one of two possibilities). Any chance of a hint?

[Feadoor]

I think I might have missed this neat break-in. After a lot of staring at it, I did a short bit of trial and error to determine the extra regions area (which I'd already narrowed down to one of two possibilities). Any chance of a hint?

You can work it out using only the 1s.

[detuned]

That is what I did - maybe I did get it after all then! I was also looking at something for some clone interactions that might have involved the four cells at R5 C1,9 and R1,9 C5 for example.

[Puzzle_Maestro]

I’m fairly certain my breakin also involved the 1s.

[Feadoor]

That is what I did - maybe I did get it after all then! I was also looking at something for some clone interactions that might have involved the four cells at R5 C1,9 and R1,9 C5 for example.

The polished way of looking at it is (ROT13): Vs gur zvqqyr nern vf gur rkgen ertvba, fb gung gur bgure gjb ner pybarf, gura 1 va obk 2 vf yvzvgrq gb E3 naq va obk 6 vf yvzvgrq gb P7, yrnivat abjurer sbe n 1 va obk 3.

But in reality you're most likely to stumble upon that route by using trial and error, and only later be able to express the logic concisely.

[Feadoor]

I've been making some more puzzles. A whole bunch of Classic Sudoku this time. Enjoy!

[puzzlemad]

Thanks for these Sam. I'm very slowly working my way through them. As an aside, for us that are not great at solving Sudoku it would help if the grids were larger to give us more space for having to put candidates in etc. I've finished up copying them to enlarge them out, but a faff. Thanks.

[detuned]

I enjoyed these a lot Sam, thanks for posting - really top notch quality, and a satisfying level of difficulty for sure. I'm fairly certain I overthought a couple of them with suggestive patterns though

[david mcneill]

I also enjoyed these. I forced myself to solve them logically. Very slow on one puzzle where the penny didn't drop for a while. Another puzzle was a work of pure evil - right up my street.

[Feadoor]

As an aside, for us that are not great at solving Sudoku it would help if the grids were larger to give us more space for having to put candidates in etc.

Thanks Liane, I'll bear that in mind in future.

Tom/David, I'm glad you enjoyed them. They were a lot of fun to create. I am intrigued which one you think was evil, David!

[puzzlemad]

Thanks Sam. The first two lots were fine - just the 3rd set.