A Sudoku Whose ONLY Clue Is A Single Line???
Vložit
- čas přidán 15. 06. 2022
- ** TODAY'S PUZZLE **
This might be the most ridiculous sudoku we've ever featured. Simon is still shaking his head about this puzzle actually existing. The Miracle Sudoku was miraculous but this... this is SO ludicrous... welcome to Jörmungandr by Jay Dyer. Prepare to have your mind blown.
Play the puzzle at the link below:
tinyurl.com/yt5dzj2f
Rules:
Contained within the grid are nine non-overlapping 3x3 square regions, which must be located. Each region contains the digits 1-9 once each such that no digit repeats in any row or column. Cells outside regions do not contain digits. Along the line, each time the line passes through a region, the sum of the digits on that pass sum to the same value. If the line passes through a region multiple times, each pass is summed separately.
If you manage to solve this one and want more sudoku then give this puzzle from Sam Cavnar-Johnson a try:
app.crackingthecryptic.com/su...
It's a classic sudoku with a very cool trick. On Patreon we've released a solve video showing Mark's solve (not knowing the trick) and then Simon's explanation of how to go about it differently :)
For those of you interested in the puzzle Adventure by Jon Schneider (mentioned in the video) there is a video here:
• The Hardest Puzzle Eve...
** PATREON REWARDS JUST OUT **
Join us on Patreon to participate in the two new competitions! We have two amazing sudoku packs from Panthera, TheAsylum and grkles themed around Japanese Sum Sudoku (which make pictures in the grid if you solve them correctly!).
We've also got Mark's Platinum Jubilee Sudoku and a video on how it was made.
Just $2/month here:
/ crackingthecryptic
▶ Contact Us ◀
Twitter: @Cracking The Cryptic
email: crackingthecryptic@gmail.com
Our PO Box address:
Simon Anthony & Mark Goodliffe
Box 102
56 Gloucester Road
London
SW7 4UB
(Please note to use our real names rather than 'Cracking The Cryptic'.)
▶ SUDOKU PAD - Our New App ◀
It's OUT on Windows (released yesterday!) via Steam here:
store.steampowered.com/app/17...
You can now input your own classic sudoku puzzles into our software using our new App! The app also comes with 12 handmade puzzles from us and we're also releasing occasional bonus puzzles too. Already available on IOS and Android.
**************************************************************
▶ OUR ARROW SUDOKU APP IS OUT ON ALL PLATFORMS!
Here are the links:
Steam:
store.steampowered.com/app/16...
App Store:
apps.apple.com/us/app/arrow-s...
Google Play:
play.google.com/store/apps/de...
▶ OUR KILLER SUDOKU APP IS OUT ON ALL PLATFORMS◀
apps.apple.com/us/app/killer-...
store.steampowered.com/app/14...
play.google.com/store/apps/de...
▶ SIMON REACTION BOARD (!) ◀
With thanks to Andrea for creating this :)
simonreacts.avris.it/
▶ CTC FAN DISCORD SERVER◀
/ discord
NEW: Guide To Our Discord Server:
tinyurl.com/CTCDiscordGuide
▶ OUR BACK CATALOGUE - ALL CATEGORISED WITH LINKS!◀
tinyurl.com/CTCCatalogue
▶ NEW CRACKING THE CRYPTIC MERCHANDISE◀
teespring.com/en-GB/stores/cr...
▶TRY OUR CLASSIC SUDOKU APP◀
AppStore: apps.apple.com/us/app/classic...
Steam: store.steampowered.com/app/11...
Android: play.google.com/store/apps/de...
▶TRY OUR SANDWICH SUDOKU APP◀
AppStore: apps.apple.com/us/app/sandwic...
Steam: store.steampowered.com/app/11...
Android: play.google.com/store/apps/de...
▶SEND US PUZZLES TO SOLVE/CONTACT US◀
crackingthecryptic@gmail.com
▶FOLLOW US◀
Twitter: #crypticcracking
@crypticcracking
Instagram (for how to solve daily clues from The Times): crackingthe...
▶Logo Design◀
Melvyn Mainini
Thank you so much for this, that was a joy to watch! If I hadn't seen your reaction when you opened it I'd think you'd been looking at my solution document because that was an exemplary solve! You actually improved on the intended path in a few places. Also fun fact: as well as being the name of the world serpent in Norse mythology, Jörmungandr translates as "huge monster", which I only found out afterwards, and really like.
👏👏👏
Amazing construction.
Thanks for creating this beautiful monster 😉
Incredible puzzle, Jay! Simply incredible.
Again amazing, astonishing puzzle from you!! That you made Simon laugh cry at the beginning. Just mind blown that you constructed this.!
Jormungandr is the 'world serpent' of Norse mythology. A sea serpent, sometimes said to encircle the entire world
A very fitting title then
Learned that from Magicka
Related to the Worm Ouroboros, I guess?
With Hela and Fenrir, is one of the three children of Loki prophetised to bring the Ragnarök. A very small serpent at birth, the gods threw it in the sea thinking there was nothing to fear, well... they were wrong.
@@timbeaton5045 Doesn't look like it.
In modern media people have made the connection a lot, which isn't that surprising given the whole tail-biting and ties to fate, but as far as I can tell, it doesn't seem like there's actually any relation between the two.
To simplify, it seems like Ouroboros is a symbol representing the eternity of existence and Jörmungandr is an angry worm flexing his size.
If I had to hazard a guess, Jörmungandr grabbing his own tail is a coincidence stemming from an emphasis of his sheer size. His story is more about judgement (or mis-judgement) than anything to do with time or unity. Some view him as a symbol of fate, but the stories describe him more like a participant in the fate others. It kind of feels like he closer represents something like the stability and collapse of midgard, given he only lets go of his tail to go fight in ragnarok, where basically everyone dies.
Once again I am shaking my head at Simon's ability to figure out the unfigurable while missing the obvious.
Missing the forest for the trees 😁
He is indeed a master at this
I'm confused how he went and explained that you can sometimes find sets of digits in these and didn't notice that the top 3 digits of columns 4 and 7 had to be the same
yeah, i sat there for 10 minutes wondering how he didnt see that the 9 had to be in the middle in the top left so that the whole row would have a 9. but i wouldnt have been able to even start the puzzle lol.
@@Shiatanful I didn't notice either lol
Simon: "Do have a go yourself."
Me: (*sees it's a 90 minute video*) I'm good, thanks. I'll watch you be brilliant.
My thoughts exactly
I made the wrong choise. 5 hours in and not even close to done
@@meesvandenberg9468 it's been 4months, how did it go?
@@ryanmackenzie6109 I made some progress. I think I will be done early 2026 if it goes smoothly.
My goodness, what a lovely birthday greeting, Simon. I am humbled and thrilled (can I be those things at the same time?) Thank you so much! I must pause my watching of the video at around 45 minutes in order to go and eat some birthday cake with friends - no kidding. Back later to finish up.
happy birthday!!!
Happy Birthday! :-)
Happy Birthday It's my dad's 75 He doesn't do YT.
HAPPY BIRTHDAY!!!!!🎉🎉🎉🎉
It is my birthday today also. Happy Birthday!
4:56 Simon's defeated "I'm gonna read birthdays" had me cracking up
Remember the times when Simon was even more outraged to receive a puzzle with only 2 digits inside ?
Now, they aren't even giving him a grid. Eventually they are just going to hand him a blanket sheet of paper.
@@leotamer5 "here is a board with 15x15 squares, numbers from 1 to 11 and you have to figure it out what squares don't have numbers on them"
all of these puzzles are just people trying to troll him in which case we'll give this 5 minutes and then we'll never see this video
@@isaacpianos5208did this actually happen?
18:10 "Unless I'm misunderstanding my own thought process" is a phrase that I never would have imagined hearing...
Yes, that made me chuckle!
I love that the logic goes from, “at least one box needs to be filled with line” to “therefore the number is 15” to “therefore EVERY box is filled with line” to “HERE’S ALL OF THE REGIONS.” That alone is stunningly beautiful and just about miraculous. The rest of it is brilliant as well. And Simon, your solve of it was INCREDIBLE. You are a genius. I never would have even attempted this. Well done! This is a hall of famer for sure. Great setting and solving, looking forward to Jay’s next CTC feature!!
PS I will note that the coloring still ended up inconsistent in a few spots
I ended up finding the regions in a totally different manner. I did it by coloring cells which had to be part of a 3x3 region and cells that could not be part of a 3x3 region. For example r1c1 cannot be part of a 3x3 region because the only 3x3 region it could be part of has a line of length 5 and a line of length 1 and you cannot have 1 cell equal the sum of 5 cells. Repeating this logic around the edges and working in, I was able to narrow down the sum until I figured out it had to be 15 and then I easily found all of the remaining regions. I do agree, however, that the way Simon did it is cool and incredibly clever.
@kevin mcknight Nice. That makes sense. I understand watching him or hearing your way, but I personally mess up even normal sudokus and it hurts my brain. Still fun though haha
I haven't caught the second deduction. I understand, why the number in one box (the one, which is completely filled with the line) is 15. However, for another boxes one may have let's say a black cell with 3 in it, and then all the lines can safely sum up to 12. Why isn't that possible?
@@DmitryMironov_page because of the rules; "along the [whole] line, each time the line passes through a region, the sum of the digit of that pass sum to the same value".
Everytime the line goes in and out of a box, which can be the same box OR another box, the sum must be the same.
@@aladoran3303 so by that logic all of the black boxes are immediately ruled out as being in the regions and all the boxes need 3 lines in and out that cover all squares.
Hey, just wanted to mention, this is BY FAR the most difficult yet incredibly rewarding puzzle I've ever solved. It took me a grand total of 15 hours, 27 minutes and 32 seconds to solve it, yet at no point did I ever feel truly stuck, I just hadn't figured out the right thing to keep advancing yet. It's such a long time to solve the puzzle, I needed to mention it somewhere... no better place than your video I guess. Figuring out the pairs was ridiculous yet so much fun, when I stumbled upon the answer I had to triple check it, I just couldn't believe that it wasn't a mistake, the answer was indeed there.
Now, I'm finally watching the video, can't wait to see where it was you found a couple of the answers. Thanks for everything, as always
That is so cool! Congrats on sticking with it for so long!
This really was a treat! It took me 7 hours but to be fair, I accidentally spoiled myself a couple of ideas when I was following along to see if I was along the right track ... but then again, I probably wasted 2 hours thinking each area had a separate sum on the lines until I came to read the comments when I got stuck so I'll take it.
congratulations dude!
well done :D
It’s hilarious to see Simon is holding mouse cursor above an easiest cell to solve, saying “what’s next? Come on, you silly man!”, then solving that cell 2 minutes later making a big logic loop. That’s totally ok, we all do such thing from time to time. Thank you Simon, it’s like seeing myself from aside
I was more disappointed that he didnt find that cell by first logic but by big logic loop and didn't even realize it was sitting there for a long time.
I didn’t know that the sum must be equal for the entire puzzle. I thought it meant each 3x3 region had its own sum which may or may not be the same as other region’s sums.
lol same, came here to see how i'm doing after getting stuck. now I'm annoyed that I spent 2.5 hours marking the regions using Kakuro logic to figure out which combinations of lengths could be valid. I got stuck after finding 2 regions and possible locations for the others and now apparently all the regions must use the same total?? Hmph.
I know i already commented, but i will reiterate, this R E A L L Y ticked me off! I have trouble figuring things out already, and this was just a kick in the teeth and im really upset about it!
Also if you're wondering why, Simon only drew one region as an example, which reinforced the idea that it only works on the same region.
There is really no other way than the sum along the lines being 15. 45 is only divisible as 3*15 or 5*9. Therefore the only possibility is 3 lines with a sum of 15 each. you can technically have 5 lines in a few places, but that would require two one cell pass-throughs, which is impossible since you only have one 9.
@@benjaminjanzen3609 Their point was that the puzzle instructions don't make it clear that the sum needs to be the same in each region. So yes, the 15 logic holds for the one region that must necessarily be filled by the line. But a region that has a blank square could have sums of 12, 13 or 14 leaving a 9, 6 or 3 respectively in the blank slot. Once we know that one box must have sums to 15 then yes, with the rules as they are we must know that all boxes must be the same.
The problem many of us, including myself had, was that the instructions were not very clear. We assumed the rules allowed for different sums in different regions, and frankly I do think that should have been made clearer in the instructions. Ignoring that frustration, however, it was a fantastic puzzle.
@@andyl7995 Oh that is an option i somehow completely missed. Somehow i assumed, that you can't have anything outside of the line. Don't recall what my reasoning was. I was asking myself the same thing, whether the sum has to be the same for each region. But re-reading it now it is quite clear that that is the case. Since the sum is related to the line and not the region(in the sentence).
OK, I'm back ... and what a puzzle (and video) this was. I paused to have my birthday party before you had any digits, but you had by some miracle deduced where the regions are. I was fascinated by the work on where regions had to be, where they could not be, whether the original cells you marked in black that had no line had to be in the regions or could not be in the regions. Then I returned to watch you figure out all of that magic with the 6789s and coloring them and ... well, it was mind-boggling for such a mortal as myself. Thanks so much for this video and solve and demonstration of so many interesting techniques - and all explained so well. There is no way I will ever attempt this puzzle myself, but I am so glad that I got the chance to watch you do it. Another region-defining puzzle, right up your alley, your clarity and enthusiasm, and again, that wonderful birthday greeting at the beginning - thank you so much, Simon (and Mark) for all that you (both) do on this channel. It is a great place to hang out.
Happy Birthday, Emily!
@@kennetsdad thank you!
I'm a couple days late, but happy belated birthday!
@@wade_23 Thank you very much!
I think my immediate reaction to this puzzle was exactly that of Simon in this. How on earth is this possible to solve and then, secondarily, how on earth was this constructed (Jay Dyer - i think a setting video is in order). I was equally surprised with myself that i managed to solve it and in a time that is comparable to Simon (so double yay me). Quite stunning in construction and execution.
Rules: 01:41
Let's Get Cracking: 07:40
What about this video's Top Tier Simarkisms?!
You Rotten Thing: 3x (1:16:51, 1:18:03, 1:18:03)
Bobbins: 1x (48:17)
The Secret: 1x (15:22)
And how about this video's Simarkisms?!
Ah: 18x (16:10, 18:03, 25:56, 36:40, 45:48, 45:54, 49:51, 51:19, 56:10, 1:00:28, 1:01:30, 1:11:39, 1:13:10, 1:13:21, 1:17:03, 1:18:53, 1:21:44, 1:22:35)
Hang On: 10x (01:37, 02:01, 21:36, 1:01:53, 1:12:09, 1:12:16, 1:15:59, 1:15:59, 1:16:22, 1:21:44)
By Sudoku: 8x (41:55, 50:16, 1:03:44, 1:23:43, 1:27:09, 1:27:31, 1:28:19, 1:29:03)
Obviously: 8x (05:29, 11:07, 19:37, 29:57, 31:24, 43:31, 43:37, 1:25:17)
Pencil Mark/mark: 8x (51:38, 58:49, 59:22, 1:00:48, 1:03:36, 1:03:38, 1:14:51, 1:17:21)
Goodness: 6x (56:10, 57:24, 1:17:46, 1:17:53, 1:20:37, 1:22:35)
Sorry: 6x (48:46, 48:46, 48:52, 49:43, 55:31, 1:19:13)
In Fact: 5x (01:39, 13:49, 33:51, 1:01:32, 1:19:08)
Nature: 5x (28:52, 34:36, 1:04:10, 1:19:29, 1:22:54)
Good Grief: 4x (1:03:04, 1:07:46, 1:17:29, 1:28:19)
Brilliant: 3x (01:21, 05:21, 1:31:30)
Extraordinary: 3x (38:31, 1:31:56, 1:32:10)
I've Got It!: 3x (29:46, 29:46, 1:30:40)
Progress: 3x (1:13:12, 1:13:14, 1:26:56)
That's Huge: 3x (1:07:31, 1:07:33, 1:23:58)
Useless: 2x (1:09:00, 1:11:59)
The Answer is: 2x (1:05:01, 1:23:35)
Clever: 2x (32:26, 32:28)
Beautiful: 2x (37:11, 1:20:02)
Fascinating: 2x (1:31:39, 1:31:43)
Surely: 2x (1:04:38, 1:25:48)
Wow: 2x (1:12:38, 1:12:40)
What a Puzzle: 1x (1:31:58)
Bother: 1x (1:10:07)
Apologies: 1x (1:05:22)
Nonsense: 1x (53:28)
Naughty: 1x (1:17:53)
I Have no Clue: 1x (04:25)
Stuck: 1x (51:48)
Lovely: 1x (37:22)
Incredible: 1x (05:42)
Gorgeous: 1x (1:21:14)
Magnificent: 1x (00:32)
Disappointing: 1x (1:06:44)
Corollary: 1x (1:07:58)
Full stop: 1x (1:32:04)
Cake!: 1x (05:31)
Most popular number(>9), digit and colour this video:
Fifteen (47 mentions)
Three (125 mentions)
Green (55 mentions)
Antithesis Battles:
Even (7) - Odd (0)
Outside (2) - Inside (0)
Black (20) - White (1)
Column (22) - Row (12)
FAQ:
Q1: You missed something!
A1: That could very well be the case! Human speech can be hard to understand for computers like me! Point out the ones that I missed and maybe I'll learn!
Q2: Can you do this for another channel?
A2: I've been thinking about that and wrote some code to make that possible. Let me know which channel you think would be a good fit!
someone has too much time on their hands to record all this
It's a bot :)
@@Wecoc1 sure it is
"I'm tempted to pause the video and go off and cry" - and thats just reading the rules
Good bot!
Simon’s despondence as he resigns to read the birthdays is exactly the emotion I felt when I tried and failed to start this solve.
"Along the line, each time the line passes through a region, the sum of the digits on that pass sum to the same value."
This rule tripped me up. There are two possible interpretations to this:
1) The sum in each subsection of the line always adds to the same value (so for example, if the sum is 8 for each segment in one region, it must be 8 for all regions).
2) The sum of each subsection of a line within a given region is the same, but not necessarily the same for all regions (meaning that for a single 9x9 box, each subsection of the line must add to the same value, but different boxes can have different sums).
I wish a clarification or example had been provided because this ambiguity is messing with my attempt to solve this.
I decided to come back to answer this question for the benefit of others:
- The first interpretation is correct. In other words, every segment of the line, regardless of the region it's in, will add to the same value.
Hope this helps anyone who might be struggling.
I had the same doubt about the formulation of the rule.
Ohhh thank you for this. I’m not a solver just a watcher, but his 15 logic for every box had me veryyy confused until now
Ya I had a bit of rethinking about that too.
Yeah same here. I didn't understand the "15" part at all until I reread the rules
This is what makes the channel for me. The mix of cleverness and sheer enthusiasm. It was very much a "nod along" puzzle for me but I had a wonderful time watching the solve.
Same.
And finally a video you actually talk to while watching))
Interestingly, there are only two ways to fill 3 lines of length 3 in a region: 159, 267, 348, and 168, 249, 357.
For each triple you need to take one from each low/mid/high section (123/456/789) and they all need to be from a different position in that section (one is 1/4/7, the second is 2/5/8, and the third 3/6/9). If you try to add up to 15 any other way (4+5+6 or 2+5+8), the remaining digits don't play nice.
this is closely tied to the "magic square" logic (rows and columns of it)
Counting the black "empty" cells was a beautiful idea 👏
I just tested the possible positions for a 3x3 region and was able to discard a lot of them. Eventually, there remained only two valid options for the *upper-middle region* (box 2), and both were completely filled by three separate line segments, meaning that the common sum was *X = 45 / 3 = 15.*
👉 That was enough to conclude that no region could contain "empty" cells.
this. beautiful puzzle!
Watched the first five minutes. Completely befuddled, bamboozled, flabbergasted and astounded. Discombobulated. Stared at that grid for some minutes. How does this ever lead to a solvable unique solution.
Is that you, Jackie Chiles?
1:13:33 Poor 9, gets miscolored and even stays miscolored at the end when Simon fixes the colors.
Also, I'm surprised the rule mentioned early on about how in deconstructions, three 3x3s in a row/column where one is offset by 1 row/column means that the 9 offset boxes contain the 1-9 digits, isn't used more often in this puzzle. At 1:15:40 he mentions he has no way to get the top-left 3x3's 9, but by using that rule you can figure that the 9 can't be in the bottom row of that 3x3 as it already exists in the top row of the top-middle 3x3, which have to share the same 1-9 digits (and similarly, if you put the 9 in that bottom slot there, it wouldn't be possible to put a 9 in Row 3). Pretty sure it shows up a few other times, but that one stood out to me.
Not like I'd ever be able to solve the rest of the puzzle myself, though.
in addition to the miscoloured 9, I am very disappointed by the missing green border between r8c7 and r8c8
Strangely enough, I don't think this rule holds true for columns in this puzzle, only for rows.
@@abydosianchulac2 I believe the first time he mentions/explains it it's in reference to the left column of squares (but I'm not gonna go back to find out), which it still applies for. It also holds for the middle column of squares, but it doesn't hold for the right side column because that column's squars are offset too much horizontally.
@@abydosianchulac2 actually it does, at least in this example. You could look at it that way: we have two possible positions for the 9. If we were to put the 9 in the lower position, where would it go in row 3? (aka the row of the upper possible position. I have no idea how to count the rows on deconstruction puzzles, sorry :D) It can not be in either box 1, 2 or 3 but it is a complete row so it needs a 9.
I hope this was understandable, English is not my first language and I don't talk much about sudokus. Also I would have never been able to complete this puzzle, but it was fascinating to watch! The 9 just bothered me ever since he pencil marked it and I couldn't stop thinking about it
Oops, I misread your comment, but it still holds true, just for another reason. I won't delete my comment though because I spent way to much time trying to sound clever 😂
I was under the impression for a while that the number of each line pass could have been different for each 3x3 box, meaning that the theoretical 3x3 box of all line with 3 passes would be 15, but that a theoretical 3x3 box with 1 line-less square and 3 passes (3,3,2) could have all 3 of those passes be the number 12 instead. "Along the line, each time the line passes through a region, the sum of the digits on that pass sum to the same value" is a teensy bit ambiguous, I guess the phrase "Along the line" is what is affected by the phrase same value, rather than "a region."
Me too. I still think that, but have not worked out if that logic breaks the puzzle?
I wonder why the upper-right 3x3 is excluded for instance. The line goes in, catches 8 cells and leaves a blank. Those could literally be any numbers by the rules as far as I can tell. But Simon asserted blank squares cannot be included and I didn't follow any exactly.
@@michaelclarkj the rule states that each region contains 1-9 each, which implies each region cannot have a blank
@@jabermouth The boxes would still be open for numbers. Just not affecting the line sums.
Happy to see Simon using the r3c3, r3c6, etc. initial positions, I don't think he's done that in any of the previous deconstruction puzzles. Seems like the best way to start this type of puzzle.
I figured out that trick during one of Simon's previous solves, and I was pleasantly stunned to see him incorporate that logic today!
So today, when I was watching this video (and it is an amazing puzzle), the audio suddenly cut out.
Then my mother shouted from the kitchen "There's some guy in my earphones talking about Sudoku." She was talking about her Bluetooth earphones that can never decide what they're listening to.
We resolved the issue, but not before laughing about it.
I love Simon's approach, way of deduction, attitude, vocabulary and tone. I could watch him solve these puzzles all day long.
Just been sat watching this and my jaw never closed for 90 minutes, How could this puzzle exist? Well done Simon, for solving this one. Jay Dyer, thank you for creating this masterpiece. I'm off to bed as it is nearly 3am here.
It's pronounced Your-mun-gander
It's the proper name of the Midgard Serpent, which is a giant snake is Norse mythology
Wikipedia gives the pronunciation [ˈjɔ̃rmoŋˌɡɑndr], in which the first vowel can't be right, since [ɔ̃] is the nasal o in French "son". So your "Your" for the first syllable looks convincing (assuming that Norse ö is not the same as modern German ö). Wikipedia's trying to tell us the second syllable is something like "mohng", but so far you're ahead in the credibility stakes so I'm going to take that too with a pinch of salt.
@@robert-skibelo I'm giving the most rudimentary phonetics. You can get closer accuracy, but I'm just going for function
Also mon and mun are subtly different, but I'm going for the flatter vowel because it's easier to phonetically pronounce since "mon" can be unintentionally stretched to "mawn" when read while "mun" is shorter since to stretch it the person might as well write "moon" or "mewn"
As for "gander" I know that A is flatter than would be wanted, but "gunder" didn't feel right either. It's an odd vowel for the English palate
the black magic he used to solve the puzzle is the same sorcery he used to make me watch him solve it for an hour and a half. good on you for being such a captivating puzzle solver!
I like how Simon jumps for joy over finding a line that has both blue and orange in box 1... while ignoring the blue/orange pair in box 4... Why I feel sorry for those clues so much I don't know, but here I am making sure they did get noticed.
Your reaction and the decision to read the birthdays was so comedic. I cant wait for the solve!
I sure am feeling special and uppity today. It took me less than 5 minutes to figure where the squares were and Simon took 35. Of course, Simon was explaining everything as he went, which I didn't have to do. Still, I'm feeling good.
Just so you're aware, it's pronounced "Your-mun-gand-her" and it is the World Serpent from Norse Mythology. It's my favourite mythology, it's so cool to hear it in another niche I love. It is said to have circled the entire known world! Must've been a big guy
True hahaha
If I was a setter, something I would have wanted to try doing was a puzzle with a single line going through every cell. My thought would be to try and see if a Palindrome could possibly work. But this is great too. :)
that sounds awesome. hopefully it’s possible and doesn’t give a symmetric puzzle without a unique solve
I'm really hoping for an April Fool puzzle with this ruleset where the region sum *is* 45 😂
A few weeks ago (presumably while working on this puzzle), Jay asked on Discord whether anyone had a good proof of the fact that Simon starts with here (that r369c369 are always in boxes in a deconstruction). Given how much work Simon had to go through to demonstrate it, I though I'd drop the simpler proof I came up with here.
Because a box spans three consecutive rows, each box will have three cells each in a row whose number is 1 mod 3, a row that's 2 mod 3, and a row that's 0 mod 3. In the first two cases, there are four such rows; but, there are only three rows that are 0 mod 3; so, with nine boxes and only eleven cells in a row, each of rows 3, 6, and 9 will contain cells from three boxes. Similarly, the boxes that appear in one of these rows each need to take cells from a column that is 0 mod 3; but, there are only three such cells in the row (those in c369); so, all three such cells in each of these three rows must be in boxes.
An explanation without using mod for the non mathematicians (without explicitly stating it anyway):
You can't have more than 3 boxes in a row / column. So the overall pattern is a 3x3 with gaps.
If the boxes are furthest left then they occupy c123, c456 c789.
If they are furthest right they occupy c345, c678, c91011.
Therefore each of the left boxes definitely occupy c3, the middle must occupy c6, and the right must occupy c9.
The same works for the rows.
I think the shortest proof is that you can't place a box without covering one of those cells, and no box can cover two of those cells, so each box covers one cell.
@@AKQuaternion Elegant. I like it!
@@AKQuaternion Certainly true. The argument I posted is essentially a more rigorous way of showing that any box placed must cover one of those cells.
The other way to see that there must be at least one box that is covered in line is to look at boxes 5 and 6. There is only one cell with no line that either of them can contain, the one just to the left of your orange dot. So at least one of those two boxes must be entirely line.
I figured the same, and as a typically GAS level solver, I was pretty pleased with myself.
I've never seen a man more cheerfully defeated than Simon in the first 5 minutes of this video. Bonkers that this has a solution
I love the idea of the alarm guy overhearing Simon calling his puzzle naughty.
I love how Simon makes these difficult puzzles seem straightforward. His enthusiasm is so genuine!
Simon. There seem to be a fair few who follow you that do these types of sudokus quite quickly. Would there be any interest in you doing a video where yourself and a few others do a live solve (individually) so we can see a few different ways of reaching the same outcome. It might be quite interesting to see a few solves happening simultaneously, and you could each talk through it at the end. Just a thought
There are a number of solvers that have started making their own videos, occasionally doing the same puzzles that end up on CTC. It would be interesting for them to all get together and discuss their own solution paths, though I think most of that discussion already happens in the comment sections.
@@stephenbeck7222 would you have any of the channel names? I'd be interested to watch. Thanks
Happy birthday, Emily!!!!!! Totally agree with all of Simon's glowing comments about your contributions as part of the CTC family!!! Simon, I've watched @ 10 minutes of this video and if it was me, I WOULD pause and have a long cry. Still going to watch to see you figure it out! (because I know you will!!)
Thank you, longwaytotipperary!! I am "chuffed" to use a British expression. 😊😊😊😊😊
@@emilywilliams3237 Did your hubby provide lot of 🎂???? Hope you had a joy filled day!! 🍷
@@longwaytotipperary He did provide lots of cake, a massive amount of cake, enough for even Simon's instructions to be followed! I had a great day, thanks.
@@emilywilliams3237 That's wonderful, Emilly! 😊
Fifteen shall be the number thou shalt count, and the number of the counting shall be fifteen. Sixteen shalt thou not count, neither count thou Fourteen, excepting that thou then proceed to Fifteen. Forty Five is right out.
What other things do you want us to argue about the nature of, my lord?
I've rarely sat and watched 90-minute videos on CZcams. The fact that I was this glued to, and riveted by a Sudoku video for this long is amazing.
What an absolutely amazing puzzle, completely deserving of the name Jormungandr. And a brilliant solve, ontop, too.
11/10 ⭐
I simply learn so much about problem solving in general from these videos. How Simon starts off simply doing what he can, adding colours here and there, and slowly building logic and meaning into the puzzle is a marvellous thing to witness. Maybe I'll try one of these for myself one of these days 😬
Oh Simon (and Mark) what an absolutely brilliant and hilarious introduction to this video when you opened the puzzle and reacted to it! 🤣🤣🤣 Thankyou Mark for ensuring that we got to see this. 👍
There could have been a box with the line entering and exiting 5 times (the one with the red square in the middle top position) but then you would have had a 3x3 with two nines sooo still not possible... It's so cool watching you solve these crazy puzzles :)
A palindrome can't work without tweaks because only a central digit can appear on any palindrome an odd number of times. Therefore the minimum number of palindrome lines to fill a grid (they don't have to be all the same length) would be nine. But it might be interesting (as here) to leave 8 blank cells, which would then have to be all different.
Except for the endpoints of the line, the middle digit of a 3x3 box always has to be part a 3 length piece of the line or more. This puzzle only has one end point that can be in a middle.
I don't think I've ever laughed out loud upon reading the rules to a sudoku before. That is absurd.
always love the puzzles. i found a nice way of proving that those 9 squares at the beginning contain a box. If you color in row 3, 6 and 9, then any 3x3 box will intersect exactly 1 line (they're too far apart to for a box to intersect 2 lines, and too close to fit between them). each line being only 11 squares wide can only contain at most 3 boxes that intersect it. there being 3 lines and 9 boxes, they each have to contain exactly 3 boxes each. with 3 boxes on each line, its impossible for the 9 colored squares to be empty
I believe the standard pronunciation is "YOUR min gone durr," where "min" is severely abbreviated (more like 'mn' without the vowel).
I solved this in about 79 minutes, taking much less time finding the regions and more time on the digits than you did. I agree fully, it is a fabulous puzzle, one of the best I've solved.
Great puzzle, lots of nice logic - there were some possible deductions overlooked at times, but of course it's easy to say that as a spectator. Good job Simon!
I'm so terrible at sudoku and would be absolutely lost on this, but it's so interesting to see and experience the way you are thinking your way through puzzles like this one. Well done and keep it going!
I’m quite young but I really enjoy sudoku / watching you solve ridiculous sudoku puzzles, and trying to solve them before you do. but this puzzle really had my brain in knots. I just wanted you to know that overall you’ve become apart of my mounting routine to get my brain running in the beginning of that day. Thank you for the amazing content!
I wanted to point out that there is a possibility of a single line entering and exiting once. In the very top-right, the 3x3 in the corner could have a region sum of 40 with the extra cell containing a 5
But he's trying to find an example 3x3 that not only enters the 3x3 once and leaves once, it also has to visit all nine cells in the 3x3. (Listen at 22:00).
He just wants to disprove 45 is the factor, since he know the sum value is a factor of 45.
39:35 for me.
Chaos Construction puzzles are almost always my favorite kind to solve, and this was certainly no exception.
start your own channel if that was really your solve time.
Knowing he could’ve disambiguated that 9 in the top left by sudoku and then he said he couldn’t due to the deconstruction rules physically pained me. You know a 9 has to go in every box and every line so therefore the only place for it in row 3 is the middle of the first box.
This puzzle was absolutely amazing! Simon's solve path was nothing less than a work of beautiful genius. This puzzle absolutely stumped me from the very beginning so I mostly just sat back and watched. These sorts of puzzles are why I have become such a fan of Cracking the Cryptic! Thanks so much again to Simon, and the setter!
That 9 painted pink/green on the bottom right it's driving me crazy :P.
I usually start by reading the rules before they are explained in the video. And for a moment I was like - this is a funny way of describing normal Sudoku. I mean how many configurations of 3x3 squares you can put into 9x9 grid... xD
Amazing! I was trying to imagine the regions as if they were still line up but it’s literally just using the column and it made much more sense. Bravo!
Incredibly beautiful. Many thanks Jay (I can’t even begin to imagine how you created it) and Simon (one of your greatest solves and a fantastic watch). What a sudoku! :)
At 1:15:40 you can get the last 9 quite easily. Where does the 9 go in row 3? It must be there somewhere as there are 9 valid cells in that row.
I think that is the first and only time I will see something that Simon didn't, what a fantastic solve of a fantastic puzzle 🤩
Before that at 1:03:04 there was the small matter of 6 in column 7 that didn't come up, but would have placed the 9 in box 9 at 1:04:58 when it was appropriate to ask where 6 goes in column 9. Simon is notoriously resistant to sudoku, when there are more interesting things going on in the grid. :)
What an increasingly beautiful puzzle. The geometry was especially brilliant which makes me a little sad that you missed a lot of the tactics I used, but still an enjoyable experience watching you experience this masterpiece.
Your pattern recognition and outside the box thinking are simply marvelous!
What a joyous solve this one is. While I don't have as much time for sudokus at the moment, squeezing in one hour and a half (or is that 45 minutes at 2x speed?) of puzzle solving watching at about 3am is surely good for the soul in some circumstance, right? Again, brilliant to watch and what an incredible feat of setting by Jay. Congratulations all around!
This is one of the greats. Extremely rewarding solve with a really fun, outside-the-box path :)
Great puzzle, another quite hard ones. I got on with the regions well enough but when they were done it felt almost like a restart. I coloured the high digits aswell and every step felt hard and earned until at the end the puzzle unravels beautifully. Very well crafted 2in1 sudoku extravaganza. Marvelous.
"Swedish volcano" must be the funniest thing I have heard from a sudoku video. While I haven't seen many of them, to a (unprofessional) geologist volcanic activity in the Scandinavian mountain is hilarious. Great vid by the way!
this is the most brilliant thing i’ve ever seen. ONLY ONE LINE. i did not have the courage to try it but watching simon solve it had me in awe throughout the video. this was magical, thank you jay dyer :D
It's impressive to me how you approach these puzzles. You're constantly challenging your assumptions, like you are trying to write a proof for a math class. I can't say I take my puzzles that seriously; I make incorrect assumptions all the time 😂. But that's probably because I am doing that all day at my job as a programmer, and, well, this is your job :D . It really just gives me a totally different view on puzzles :)
That was incredible! I intuited that you wouldn't be able to have a single-cell line segment although it wasn't until afterwards that I was able to _post-hoc_ justify it to myself, so using the nine 'seed' cells I was able to build up the nine regions, started marking cells as high and low, and worked out all the 3- and 4-cell combos that added to 15. I realised that any region made up of three 3-cell segments would _have_ to have one segment with two high digits on ... and then it went 🍐 shaped because I saw that 1-6-8 was a valid possibility and missed that 2-6-7 was also in there ... and I had gone a long way after pencil-marked the run in "box 9" along row 11 as 1-6-8 before I realised the mistake and didn't have the energy to rewind it and go again 😱
I love watching you solve all these puzzles. The exclamations you use especially in this video are so good…my favorite one was oh botheration!
Colouring high-low helped me a lot. It made some things easier to spot, for example, and told me the nature of a bunch of cells that Simon missed for some time.
I found the geometry Simon noticed at the beginning enormously helpful throughout the puzzle. Kinda disappointed Simon never used it again.
How so?
How do you even set this? Amazing work, Jay!
After one hour there was the „blue and orange on the same three cells line“ situation.
I love the way you verbalize your thoughts. It allows me to follow all along, not feeling like a unworthy student ☺️
Probably the most mind bending sudoku I’ve ever seen. Absolutely amazing that Simon actually solved it in 90 minutes.
31:52 but I don't understand, why can't a black cell be, for example, a 3, and then every time the line comes in, it picks up 14 worth of digits?? (assuming the line enters 3 times)
The total is the same for every line of every box (not each box independently). He already proved that there must be a box that covers all 9 digits, so the total must be 15.
Totally agree
@@Tahgtahv ooooh I missunderstood the rules then
@@onlysnl i misunderstood too. I thought the amounts were different per box.
It has occurred to me that the wording of the puzzle could be interpreted to mean that although each pass of the line through any region gives the same sum, this sum is not necessarily the same for all regions.
In any case my first attack here was to consider all 81 possible 3 by 3 boxes and eliminate the ones where the line configuration was impossible. This included:
A box with no empty cells and number of segments not being a factor of 45
A box with more than one 1-cell segment
A box with a 1-cell segment and a segment 4 of more cells long. More generally a box with a 1-cell segment and k other segments using m cells where triangular_number(m) > 9k.
I marked the valid boxes by colouring their upper-right corner.
Given the knowledge that 9 cells in the grid *must* be in boxes it was possible to eventually place all the boxes. I think that in doing so I did assume that *all* the totals were the same (15) throughout the puzzle once I placed one box with 3 segments and no empty cells.
The phrasing of the rules appears, to me, to be very deliberately worded to indicate that each box is its own thing, each box's line sums apply to that single box only, and sums can/will differ between boxes. If the entire puzzle has one constant sum across all boxes, the rules really should use different language and say so. Especially if knowing that is required to solve or completely changes the solution path.
I've been attempting to draw the regions, assuming all boxes' sums are independent. I discovered and used all the logic you mentioned. Once one box was placed, I was able to use its 6789 quadruple to further restrict other boxes. I'm just not sure if it's fully possible to place all boxes without knowing all totals are the same. I've placed two boxes and strongly restricted all others to two or three possibilities, but I appear to have gotten stuck. I suppose I'll keep trying before "cheating" and using this knowledge of a single sum across the puzzle.
The rules almost never confuse me on this channel... two or three times in two years! Usually the phrasing is incredibly clear, so it really stands out when the wording is ambiguous or misleading in some important way. I have not watched the solve yet, spoils the fun of trying, but getting stuck, I did just click a bit into the video to see how Simon approached it for a hint. I don't see a way to infer that all boxes must have the same sum, and found it surprising that he very quickly assumed they do. Good comment, good observations.
I was relieved to read this comment! I took the same approach and do feel that the instructions are ambiguous.
I believe Simon made a leap in logic asserting that empty squares cannot be in allowed regions. Or if he justified it, I wasn't able to follow his reasoning. I remain annoyed.
Omg that break-in was amazing... Afterwards, I thought perhaps high low coloring was the intended path, but I liked watching better than trying for myself... Well done Simon!
I'm not even what one would call a casual sudoku player but I find these videos absolutely fascinating. I took a look at the puzzle before watching the video and was able to deduce a lot of the clues you used (the cells that must be contained in a region as per deconstruction puzzle rules, the line-less cells) and was able to locate the regions using slightly different logic. I figured the line-less cells couldn't be used in any box since that would mean each box would need one, and as you pointed out there were only eight line-less cells so that couldn't be the case. I then used geometry to force each box in place starting with the middle left forced-cell, the one that was blue in your solve. I was also able to intuit that each region must have the line pass through it the same number of times, which helped me force some regions into place.
However, beyond that I was stumped, likely because I'm not familiar with the the regular sudoku/equal sum strategies you utilized for your solve. I particularly appreciated the use of split-coloring the cells.
Good stuff!
Feel like letters to differentiate the flavors of orange and blue might have been less confusing than color-flashes...
Happy big birthday Emily!! Did you have lots of cake??? Pleasure every day to read your elegantly written comments. Hope that you have a wonderful and fabulous day!!
Thank you so much, David. I am pausing in my watching of the video so that I can go and eat some cake, in fact! More later. 😊😊
38:25, oh no! Simon omits to outline the lower green region completely. Now I can't sleep!
Have to smile when Simon is surprised once again by Svens marvels right at the end with the solve is correct button working
LOL @ "Sweedish Volcano"
It was truly an honour to see how your brain worked to solve this puzzle. Truly beautiful to see! Thank you for sharing with us
That was pure joy and madness, despite those words shouldn't be together 😂 and filled with all those "look at that digit, it's obvious!" moments, just to be railed right away by some line of thought uncovering a whole chunk of the puzzle. Congrats, to both solver and creator. 👏
I love watching him complete these puzzles because I try the puzzle before I watch his videos and then if I give up or something I just watch the rest of the video and see him complete it
This was out off this world. Simon you have done it. Super great yet unexpected solve.
This was a really pleasant puzzle to solve. I spotted the 'empty cell' entry way too quickly for my liking, and spent about 20 minutes trying to prove if I was wrong or not. After that I think it came quite logically, but not quickly. I got the 6789 importance, and even thought to colour them myself, going on later to colour 4/5 pairs to help me finish the solve.
I must say, this puzzle shows the effect this channel has had on me at least. No way in a million years would I have been able to solve this before finding this channel, but now, after watching Simon and Mark solve countless puzzles, I feel like I have a whole arsenal of sudoku tricks up my sleeve and am not really scared to try any of the puzzles I see, even when the video is over 90 minutes long.
Thanks to both Simon and Mark for the exposure. Thanks to Sven for creating the amazing tool. Thanks to the fantastic setters for coming up with more and more beautiful puzzles.
LOL , WOW. OMG, THAT WAS THE CRAZIEST PUZZLE IVE EVER SEEN. AND YOU CRACKED IT, THAT IS JUST ASTONISHING.
It took me three hours to solve the puzzle, but each hour more exciting than the last. Thank you.
What a joy to solve. Needed a *small* hint in the middle of the puzzle, but I did alright. I love watching you deduce things within 30 minutes that took me well over 2 hours to deduce LOL
This was a pleasure to watch you solve
1:40:52 for me. I spent a LONG time testing lots of possible boxes to remove the single cell = sum of 4 cell boxes before I stumbled on the empty cell theorem and even after getting the boxes I found it hugely challenging to disambiguate my high and low numbers.
I solved this before playing the video and was amazed at the way you highlighted the "middle" cells in the beginning, which would have greatly sped up my building of the boxes, so thanks so much! I also didn't appreciate that the "offset" lines such as the top of box 2 acted as the "remainder" of line 4 and stuff like that, although you managed to forget that yourself at 1:15:41 when you could have placed the final 9 immediately either by saying that row 3 has 9 digits and so there MUST be a 9 on it somewhere, or by observing that r4c2 "sees" the 9 at the top of box 2.
Even at this late stage it took me ages to get any digits because I didn't see this stuff either, but when you gave out your secret techniques and then later passionately lamented the pains of working with the silly deconstruction rule, I did think it was amusing that I wouldn't have realised it was solvable from that point unless you gave me the necessarily tools earlier in the video!
Also - 1:23:11 - where the heck did this come from? As soon as you explained it this was obvious, but you plucked that bit of logic up from nowhere it seems! Love how observant you can be while looking at something completely different in the puzzle haha!
Brilliant puzzle and brilliant solve. Thanks Simon!!!
I didn’t realize the black, empty cells were not in a region until after I had figured out the regions! I did it by coloring all possibilities for each square, then removing them as I disproved each 3x3 option. It quickly became apparent that at least one region would have to 3 passes of 15, so with knowledge, the rest of the regions fell easily into place. The 2nd part of the puzzle was much more difficult! Great Job!
that one took me 164 minutes, I was a bit faster with finding out the 78 pairs (I wrote down different possibilities for number sequences), but had two tiles coloured wrong and it took me ages to find my mistake.
Great job on this one, truly genius, especially seeing how you are able to find the solutions without having possible line combinations mapped out!
Beyond the beautiful logic, the puzzle itself is a work of art. I'd love to have it on my wall!
Took me three hours, 41 minutes, and 35 seconds but I solved it. Most puzzles you feature, I just get bored/stuck, laziness wins, and I just end up watching your video instead; this one had me captivated until about 2:30 AM solving it. Word of warning to anyone else: it appears a website update broke the checker for this puzzle, as I had the same solution as Simon but the check button decided to try and give me a heart attack instead.