Time To Test Your Sudoku Skills!

[@persephonetsebelis8948]

Honestly, the birthday shoutout made my whole life!! Thank you so much

[@pouletbelette]

Happy birthday!

[@shangaiguarisnaque9277]

Happy birthday!

[@LiquorStoreJon]

Happy Birthday! How was the cake??

[@persephonetsebelis8948]

@@LiquorStoreJon thank you! cake is happening today at a picnic 😊 so I’ll let let you know later

[@greystar321]

Yay happy birthday :)

[@inspiringsand123]

Rules: 02:48 Let's Get Cracking: 05:18 Simon's time: 1h13m48s Puzzle Solved: 1:19:06 What about this video's Top Tier Simarkisms?! Bobbins: 3x (09:40, 58:20, 1:12:20) Maverick: 3x (05:21, 05:25, 05:25) The Secret: 3x (06:39, 06:40, 06:47) Schrödinger Cell: 2x (50:37, 53:58) Knowledge Bomb: 1x (27:31) And how about this video's Simarkisms?! Ah: 18x (04:37, 08:02, 10:03, 10:03, 12:19, 19:49, 25:50, 25:50, 32:57, 33:01, 33:03, 35:08, 35:39, 54:14, 55:23, 1:03:38, 1:07:31, 1:15:12) By Sudoku: 14x (22:57, 26:00, 26:03, 30:44, 33:15, 33:18, 46:58, 59:16, 1:00:06, 1:10:34, 1:12:53, 1:14:49, 1:14:53, 1:15:12) Wow: 14x (10:11, 10:11, 10:11, 21:33, 21:36, 35:21, 53:11, 55:27, 55:27, 59:07, 59:07, 59:07, 1:16:42, 1:16:44) Hang On: 12x (04:26, 09:52, 09:55, 09:55, 23:54, 38:37, 45:25, 59:56, 1:02:43, 1:07:34, 1:13:30, 1:18:48) Beautiful: 9x (20:59, 26:29, 29:54, 29:57, 33:04, 53:41, 59:07, 1:15:14, 1:15:17) Sorry: 6x (11:09, 22:39, 31:51, 50:58, 1:06:06, 1:14:45) The Answer is: 6x (10:42, 22:48, 33:08, 38:34, 1:01:24, 1:01:50) In Fact: 6x (19:55, 23:54, 53:33, 55:44, 1:18:21) Good Grief: 4x (25:46, 59:00, 1:06:16, 1:14:43) Lovely: 4x (12:19, 23:26, 23:29, 1:16:08) What Does This Mean?: 4x (03:41, 19:46, 27:13, 1:05:50) What on Earth: 2x (55:21, 59:49) Stuck: 2x (28:27, 35:21) Going Mad: 2x (04:37, 12:30) Have a Think: 2x (16:35, 1:09:28) Pencil Mark/mark: 2x (22:50, 57:57) Goodness: 1x (1:12:47) Clever: 1x (1:18:37) Horrible Feeling: 1x (37:51) Brilliant: 1x (01:15) Break the Puzzle: 1x (58:29) Fascinating: 1x (19:19) Incredible: 1x (11:38) Ridiculous: 1x (1:12:50) First Digit: 1x (21:33) Gorgeous: 1x (1:10:03) Shouting: 1x (00:59) Magnificent: 1x (02:05) Surely: 1x (13:08) Baffling: 1x (00:32) That's Huge: 1x (25:50) Cake!: 1x (01:23) Most popular number(>9), digit and colour this video: Seventeen, Twenty One (6 mentions) Two (152 mentions) Yellow (59 mentions) Antithesis Battles: Even (5) - Odd (0) Row (36) - Column (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!

[@andrewnanninga1966]

44:35 -I know I don’t speak for everyone but I think most of us are totally fine if you need to take time and just be quiet and think! IMO there’s no such thing as a bad cracking the cryptic video, just keep on doing what you do!!

[@cae13yt]

... and in addition, Simon, if you need to think a little and be quiet, we don't need to pause the video to get our thoughts together to keep up with your speed. 👍

[@DoongXiouHua]

38:50 Actually you can't make 7 join the 3-cell arrow and the 9 and keep enough room on the right side at the same time. 47:50 A more easy way to find out r6c5 is in blue region, is looking at r7c6, which is either yellow or 8, never going to be in blue.

[@biegeldog]

47:50 - My thought exactly. There is no way I could solve this myself but I’m always super excited when something he said 20 minutes ago comes up and I’m like “Yellow or 8 and an 8 can’t go on an arrow with a total of 8 so that can’t be blue!” Woot!

[@solfeinberg437]

38:50 - yeah, he gave it 10 spaces and said it was okay.

[@ca-ke9493]

@@biegeldog yes! It was so close he was looking exactly at that part and just missed the last step of logic for that 8 8 shenanigans.

[@olivier2553]

47:50 I saw that too, and that had been available for quite a while. 38:50 I think I also cam to that conclusion & would barely join to the 3 cells arrow if going the straightest route, but it also needs to wiggle a bit to leave enough cells for the 9.

[@tallcat]

Very glad to see this puzzle here! I made the mistake of starting it the first time late in the evening and my brain wasn't up to the task. Once i tackled it with a more alert mind, it was a joy!

[@djiboutidan]

48:00 I love the few times when I am able to see something Simon doesn't (very few times) that he then independently proves with much more complicated logic. 15 minutes earlier, you determined that between r7c6 and r7c8, one of them had to be an 8 and the other one had to be a yellow. So how could r7c6 ever be blue? It can't be blue if it's yellow and it can't be blue if it's 8 because blue already has an 8 pencil marked in row 9. Therefore, blue can't take r7c6 and needs to take r6c5.

[@cookieshop_4668]

yeah, ive been seeing the logic since hes pencil marked it, and him even accidentally coloring the right cell blue. The same thing with the nines/arrow above the yellow, as all regions have to have a 9 in them and no full region can be formed if the orange 9 is part of the arrow next to it. However, I love the roundabout big brain knowledge Simon uses to come to the points, ways i couldnt even imagine

[@jwolfe01234]

It was remarkable how horrendously complicated his proof of that was.

[@dannstarrjp]

Literally just wanted to write the exact same thing 😅

[@iain_nakada]

Same here. Was hoping he'd eventually realise, but damn that roundabout big brain.

[@ElaHuguet]

I was shouting that at him for a while!

[@SmartHobbies]

I love that you give out birthday wishes. It’s a really nice thing to do for your viewers.

[@goldenknight578]

I just come for the cake. lol

[@crystalgehrt8861]

Both my kiddos (5 and 7) are huge Simon fans, and we have watched his birthday shout-outs to them probably 100 times each!

[@Jablicek]

Currently tackling this as a group solve with 6 or 7 of us. There's been a lot of discussion already and we don't have a region defined yet, let along a number in! Looking forward to seeing, again, how much more efficient the individual is over the group :) Edit: We finished Mark's puzzle first. I'm not strictly sure we're going to finish this one at all given that it's now midnight.

[@YourFavouriteDraugr]

It's a 40-something minute Sudoku at best...

[@Jablicek]

@@YourFavouriteDraugr Maybe for you, I think it took us about five hours in the end, all up. We do tend to waffle on though.

[@istvanmagi473]

It is absolutely amazing how Simon's brain refuses to do sudoku even when he consciously decides to do sudoku. At 1:15:32 he finds a 1-8 pair in a column. Does he say "Look, a 1-8 pair! Let's see what it does in the column and in the region"? No, of course not. Instead he says "I want to join these up together" and stops doing sudoku and starts thinking about region shapes instead.

[@acballer4232]

I saw that too. And the crazy thing is that 2-8 square was the last one to be solved

[@matteopascoli]

I swear he left r5c7 for last on purpose 🤣

[@MatthewBouyack]

Yes, this drove me crazy until he finally filled it in at the very end!

[@richnewt]

@@matteopascoli I was yelling at 1:12:56 when he says "its a 128 and its not a 1....." just waiting for the "...or an 8" which never came.

[@BookofAeons]

47:30 The simpler way to see this is to note that r7c6 is either yellow, or it's an 8. Blue already has an 8, so that cell can never be blue.

[@tyfunk8614]

5:05 "I will think about something I've just thought about in a moment". I say this to myself all the time!

[@mattinm]

39:30 The 7 can’t reach the arrow and collect the 9 and leave room for the orange 9 region at the same time without grabbing 10 cells.

[@flobiish]

I'm at 47:40 and I have to point this out. Getting that last blue cell could be a lot easier. The yellow cell in row 7 is either under the blue 9, or the cell under the blue 9 is an 8, which already appears in blue.

[@G.Aaron.Fisher]

Note to the author: I would have included the rule that regions contain exactly one arrow. The logic around proving that fact is not nearly as elegant as the rest of the puzzle. It's at least worth considering constraints that aren't technically required for a solve, when they can make the puzzle more concise.

[@Brazz27]

But theres 9 arrows, 9 circles and 9 regions in a sudoku, so its kinda implied, unless Im missing something?

[@martinepstein9826]

@@Brazz27 All that means is if one region has two arrows then another region has no arrows.

[@achad1607]

@@martinepstein9826 You can immediately eliminate all pairs of 3-cell arrows [21 minimum for two numbers.] The two-cell/3-cell possible pairs could not include a four or a five 2-cell arrow. A 2-cell/3-cell 7-9 pairing is the only one to consider.

[@maxgreve7856]

Amazing, amazing puzzle! Fantastic solve by Simon, as usual. These really are my favorite kinds of puzzles! The length of these sorts of videos doesn't bother me at all, it's very entertaining from beginning to end. More, please!

[@LaytonBehelit]

The logic around 17:00 is not quite complete: you could avoid taking the corner arrow with the 8 by going through 9 and take the 3- and 2-cells arrows in columns 6,7,8. But that would leave the corner arrow without a suitable circle.

[@ericpraline1302]

Unbelievable. At first glance doesn't look as if there's enough information to start, but I actually got off to a good start, placed all the 9s, before grinding to a halt for some time in the middle. Then I managed to get my eye back in via an insight on row 7 and I struck the bullseye. Brilliant puzzle.

[@K_Bachi]

I’m extremely impressed with myself today. I somehow managed to almost breeze through this one in 53:33. I’ve done about 4 puzzles from this channel so far today, and I’ve managed to beat Simon/Mark’s times on each one, which is usually a pretty rare occurrence for me! Thank you Mark and Simon for showcasing these spectacular puzzles, as well as creating/providing more through the CTC apps! These videos and apps have helped sharpen my sudoku (and mental math) skills so dramatically I still can’t believe it. I try to solve just about every sudoku you guys showcase, especially the hard ones, because I love those “aha!” moments, and those flow states when everything just seems to click. I remember when I would take a minimum of double the video runtime to complete a solve. Now I’m pretty consistently taking no more than about 110-120% of the runtime, though sometimes as low as 65-70%! I’m finally starting to feel like I can keep up with the experts, and it’s an amazing feeling.

[@tangrybird04]

I decided to attempt this one because I was spotting a lot of things before you called them out, and I managed to get all the 9s placed, finished 4 regions and and started on 2 more regions that remain incomplete before I gave up. It took me like 30 min to spot where 8 could go in row 6, and I was kinda getting frustrated. But I somehow managed to take up a whole hour working on this puzzle…what a great sign of a beautiful puzzle

[@solfeinberg437]

38:55, when Simon says the seven arrow bulb can connect to the three cell arrow at the bottom and leave room for the 9, he doesn't count - he's giving the 7 bulb 10 spaces. The 7 can't connect to that arrow, it is orange and connects with the nine to its right.

[@Arcessitor]

I never thought I'd hear Simon say "This is sick", but he spitting mad facts.

[@th.nd.r]

No need to apologize for the length of the video here - the quality of this setting and solving more than justified it! Incredible! So many intricacies and deductions bouncing back and forth between each other, loved it. P.S. You missed the 3 in the corner again!

[@YourFavouriteDraugr]

The quality of the solving was atrocious.

[@th.nd.r]

@@YourFavouriteDraugr oh screw off with that toxic crap. If you have constructive criticism or lighthearted banter to offer than offer it, but this is a place for love and positivity, and there is no room in the sudoku community or anywhere in the planet really for just putting people down to put people down.

[@christophstahl8169]

Loved this. Whenever we can do shading / colouring / draw lines i am happy. I don't think this is that hard a puzzle really. I loved the flow and i found quite a few digits simply by looking at rows or columns, like where can 6 go in row 7. Also I found pencil-marking to be a friend with this puzzle.

[@pii-chan8804]

Don't stress Simon, we love your vids cause YOU make them, keep up the awesomeness!

[@manfredwitzany2233]

Hello Simon! your beautifdul logic at time 48 could be avoided by a simple question: Can r7c6 be blue? If it was, r7 c8 must be yellow, as this is the only possibility to take the last cell. But we know that one of said cells must be 8. This cell can't join to neither blue nor yellow having their 8s in r8 and r9. Therefore r7c6 can't be blue but r6c7 must be blue.

[@nicholasparrilla5741]

I like how Simon apologizes for the length of the video when meanwhile I pray the daily upload is a 2 hour adventure. Love the content!

[@longwaytotipperary]

Fantastic!

[@JohnRandomness105]

I disambiguated a location or two of regions by fixing 9s in the grid. Then a region has to contain an arrow, a circle, and a 9. (The possibility that two arrows and two circles could be in a region didn't occur to me. I'm treating it as an oversight of the rules statement.) Allowing the arrow in column 9 to have a 1 gave me buttloads of trouble, by forcing a 1 in R9C8. The arrow has to be 234, and find a circled 9 to match. (It's not orange.) I also managed to make progress by labeling the digits in the two 8-sum arrows other than 1, ABCD. A + B = C + D = 7. 47:55 As others commented, that cell already had to be blue, because the other candidate blue cell would contain an 8. 1:19:20 Nice to see my final solution matching the video's.

[@brianmcadam443]

For anyone that wants a cleaner way to get past Simon's extensive hypothetical at around 55 minutes, first consider row 9, specifically where 6 and 7 must live: in blue. Then consider where 6 and 7 must live in row 7. They are not in blue. By arrow sums and the existing pencil marks, 7 *must* reside in the one green square in row 7. And then 6, by elimination, must be forced into red, where it will force the arrow sum and the repeated digit.

[@CrypticCL]

Brian, do you mind explaining why there can only be one repeated digit, and not two (at that stage of the puzzle)? Simon didn't specifically explain it - other than mentioning Schrodinger, as though there would be one cell having to contain two numbers simultaneously..... but I don't see why? (e.g. 1,2,6 = 9 total in the first three cells of Row 7, and then 5,1,2 = 8 in Row 8 beneath it). It seems to me that (at that stage of the puzzle) two digits (1 and 2 in my example) could have been repeated without clashing.

[@brianmcadam443]

@@CrypticCL It basically comes down to the law of leftovers for Irregular Sudoku, and the extent of the drawn regions. Yellow in the bottom right is confined to rows 789, even though the last cell hasn't been chosen. So any digit that is on both the red arrow and the green arrow, where does it live in yellow? In row 9. Then where does it live in blue? *Above row 7* because you've already allocated that digit for rows 789. Well, given how many cells blue already occupies, there is a maximum of one empty blue cell above row 7, the one immediately to the left of the 9, which would complete the blue region. So for the 125/126 example you posited, both 1 and 2 would be in row 9 in yellow, and either doubled up in R6C5 (nope) or left out of blue entirely (nope). So you can't repeat two digits. (this is not exactly the proof that Simon uses I think, but it's the same concept of comparing groups of rows to groups of regions)

[@CrypticCL]

@@brianmcadam443 Thankyou Brian. That makes sense, and I appreciate your detailed explanation.

[@crystalgehrt8861]

Just a beautiful puzzle. Lots of gorgeous logic. I did find some nice pieces of logic Simon seems to have missed which made my solve a bit easier. Mr. Menace is menacing, but I was proud to be able to solve one of his puzzles!

[@B0110-x3d]

at the 47 minute mark when deciding the final blue cell an easier way of seeing it is with the yellows. The combination of needing a yellow and an 8 (r7c6 and r7c8) in row 7 means blue could never take r7c6, as it obviously isnt yellow and it already has an 8 pencil marked within the region. This forces the blue into r6c5.

[@emilywilliams3237]

Incredible. You were nearly at an hour before it seemed that you were confident that you would complete the puzzle. Of course we knew there was a happy ending since we are seeing the video, but it did seem as if the logic of figuring out how to proceed after getting the 6 of & 7 in row 8 was very difficult - maybe the hardest logic that I have discerned you working with on this channel. But you did it, and really, it was like a card trick: you pulled out my card from behind my own ear and I watched you do it, but I have no idea how. "I am so slow. Honestly, it's ridiculous." you said. Simon, you are brilliant about so many things, but judging when you are so slow is not one of your brilliancies. You are not slow, not in this puzzle, at least not at the end. (There may have been a few slow moments at around minute 10 ... but that was it, truly.) I will again say, incredible. What a solve. I am so happy to have had the chance to watch this video. A triumph. Thank you so much. (And I think it is so cute that you want to do the perimeter outlined in green using the wonderful line tool. I chuckled.)

[@guitartailor]

If only he had finished counting out the region that would allow the 7 to join the 3 arrow! It doesn't work!

[@kaymennens9956]

Thanks for your solve, Simon! Clean solve, but some time stuck at the major difficult deduction (as many solvers). But you persevered and managed to solve it! Thanks again! Mr.Menace

[@joelstevens5670]

Hi Mr Menace, thanks for another incredible sudoku. I hope you don’t mind but I just wanted to pass on a little feedback. I believe this puzzle is perhaps a case of having one rule too few, namely ‘no region containing multiple bulbs or arrows’. To explain, I really enjoyed solving the sudoku given a one-to-one correspondence of the arrows and bulbs, with each pair being assigned to its own region, only to find out that the rules read differently when watching Simon’s solve. As a budding puzzle setter, the truth is that not everyone understands rulesets so easily! I am quite a deep thinking and logical person and yet I would almost never have taken the rules to mean anything else but that each arrow and bulb were connected within their region (it actually took me a while to work out what Simon meant). Not knowing this does seem to take away from the solve path (which is by no means simple even with the alternate reading of the rules). I can of course see the appeal of creating puzzles to solve impressively but the beauty of sudoku can also be in the simplicity. Having said that, I have full respect at the fact that you can create puzzles such as this in the first place, it’s another beautiful idea and that deduction in row 7 was simply amazing! :)

[@kaymennens9956]

Hello Joel, Many thanks for the feedback and this suggestion. When I started setting the puzzle, I was not even certain I would use 9 arrows, so I wanted to leave the possibility open. I take your point that the addition of this little rule would not ruin the puzzle too much, but I thought it was a nice thing to discover as a solver. NB: aside from one deadly pattern, the puzzle solves without the 5 clue and it’s corresponding arrow :D.

[@joelstevens5670]

@@kaymennens9956 I see, it makes sense now in that context (so the rule to clarify would be something like ‘a region may contain more than one bulb or arrow’). I imagine that may cause a few extra headaches with solving! ;) Interesting about the 5 clue, I can’t imagine how long it took you to think of that to resolve the deadly pattern (the moment every setter loves most)! Thanks again.

[@grahamrskelly6042]

I loved the logic of getting the nine in the bottom row.

[@markp7262]

1:08:37 finish. I got stuck for a bit, until I caught the logic with the two 3-cell arrow in the bottom left. Simon did some convoluted logic to determine the arrow in red, but it could definitely be sorted out more easily. Start with r7c6 and r7c8. One of them is an 8, the other is a yellow 2-3-4-5. Since neither can be in blue, the blue 1 must be in column 5 (r6/7). Now look at r9c6. It is the other 2-3-4-5 that is not on the yellow arrow. Where does it go in blue? It is not r8c5 (that is on the yellow arrow), so it must be in r6c5 or r7c5, pairing up with the 1. Now look at row 7. The only place for a 7 is in green. The 6 can't go in r7c6 or r7c8 (see above), or r7c7 (a 6 in yellow below it). Therefore it must be in red, on the arrow. As for why the arrow matches up with the 9 in orange, it also has a simple explanation. Each region needs a 9 in it. The only possible way is for the 5 and 7 circles to take the 9s next to them (anything else would be too large a region). Since the 7-9 go in the same region, they would have to drop straight down from the 9 in order to pick up the whole arrow below. This wouldn't leave the 9 in column 9 with enough cells. The only other circle that can pick up the orange arrow is the 9 next to it.

[@RichSmith77]

He so very nearly found the problem with attempting to connect the arrow to the 7 at 38:50. He noticed a straight connection down from the 9 to the arrow didn't leave sufficient space for a region to its right. So he redrew it with a kink at 38:53. He just didn't give himself enough time to realise that kink would require 10 cells. I shouted, but to no avail. Probably because I'm four days late. 😂.

[@MyriamTT]

54:00 There you go, Simon. By Sudoku you could easily place a 7 in row 7.

[@_-_-Sipita-_-_]

When simon got stuck at around 43 mins, what he could do to advance was to realize that the green arrow digits were different than the yellow arrow digits, 1 of them would go on R9C6 and the other with the 8 on R7. Using geometry: the digits R9C(6,8,9) would be on R(6,7,8)C5 (blue cannot take R7C6 cause 8 is orange and 2345 is yellow) and so R7C5 is 12345. Looking at row 7: 7 never goes on 3 cell arrows (also no repeats) so its on R7C4, and 6 can only go on the red arrow digits, making it a 126, plus it looks at the remaining cells making green arrow cells 134.

[@Clocksmith-s9w]

My first thought when I read the title was simply, "Raise the pendulum's bob. A shorter pendulum speeds up the clock."

[@wariolandgoldpiramid]

9:39 no, Simon, that's not possible! Because this configuration, by arrow rules, would have 8 cells summing to 34, and you'd have to put 11 in the empty cell, which you can't do!

[@piarittersporn]

Every time Simon apologizes for being slow, I get an inferiority complex. Without his excellent jump-start and without checking his progress from time to time, I would probably continue to enter and delete my digits alternately for the next three days. A great puzzle.

[@chessburns]

I cant believe how Simon keeps us engaged and at the same time solves puzzle after puzzle. Btw, for those of u who r interested in Top Gun. Watch the 1986 video b4 the new 1. That said, Top Gun Maverickwas an absolute knockout of a movie. I wont spoil anything since ik some ppl will wanna watch it without spoilers. I literally watched Top Gun last night. Then today i watched Maverick. Ill say this, it pays tribute to the 1st 1. Also, theres some actors who reprised their roles like Ice. Nuff said! Off u go watching Maverick.

[@mister-8658]

7 hours and 5 minutes this was a monster of a puzzle. Genius but insanely hard

[@mikesparks3398]

Lol, another awesome solve. At one point you reminded me of Barney fife reciting the preamble when he started messing up his hair because he couldn’t figure it out, ha

[@Gonzalo_Garcia_]

51:37 for me. What an extraordinary puzzle!! That was fantastic!

[@grahamrskelly6042]

51:04 Simon is grabbing his hair! to try and stretch his brain around this puzzle. good job Simon.

[@emo6577]

The way this puzzle worked reminds me of the game Flow Free!

[@martinepstein9826]

38:52 Now the black region has 10 cells!

[@JohnHazl]

39:02 you're counting r7c8 for both regions. There's no way to get the 7 to the arrow *and* pick up the 9 *and* leave room for the orange region to get 9 cells. I think taking 20 seconds longer to look at that would have saved you 20 minutes of solving time haha

[@RichSmith77]

Yes. When he put the kink into the proposed black region, seen at 38:55, in order to give the orange region enough space, that increased the black region to 10 cells. Shame he didn't notice.

[@Coyotek4]

Another marathoner for me; took me just over 90 minutes (1:30:55) to make it to the end, and some of my logic was stretched a bit (though I'd like to think I stopped short of actual bifurcation), but dangit, I made it! Incredible puzzle!

[@GregJonesLivesHere]

This puzzle was really not so complicated 😶 So much time spent on complex (and Impressive!) but unnecessary logic when there were trivial deductions available that would make the complex part unnecessary. I still of course watched and enjoyed it all 👏👏

[@Cairful]

I loved this puzzle from start to finish and I'm really glad to see it here! I wonder how soon that 7 in row 7 could have been filled in 😉

[@alfredeinstein115]

Beautiful solve. Chaos constructions are one of my favorite variants :)

[@srwapo]

@47:50, heh, that was a long work. r7c6 couldn't be blue because that would make r7c8 yellow and both blue and yellow have 8's penciled in, so you wouldn't have an 8 in Row 7.

[@DontMockMySmock]

The logic around the 48 minute mark for completing the blue region is really complicated; you could've just seen that the other possible cell could only be 8 or yellow, and blue already had an 8 in it, so that one couldn't be blue.

[@_-_-Sipita-_-_]

39:57 for me. this sudoku was easier than i expected for an average 80 min vid sudoku.

[@stevesebzda570]

Unless I'm miscounting, that "7" CAN'T JOIN there [on those 3 arrows @38:56]. Am I mistaken? [I don't think Simon's counting the tenth one is has to use] I could be wrong though, [Simon's not seeing it, lol] 🤔😂😎☕☕

[@OlafDoschke]

Two logical tidbits up to minute 49, where you were stuck in rows 6-9. 1. Finding out whether the last cell of the blue region is in row 6 or 7: Well, the one cell in row 7 that is NOT an 8 has to be in the lower right yellow region. The other cell IS an 8 and the blue region already has an 8 in row 9. Or shorter: Cell r7c6 cannot be blue in either case: Either it is NOT 8 and therefore yellow, or it IS 8 and therefore not blue. 2. Thinking about the 6 cells of two arrows in row 7 and 8, just extend this with the 2 cell arrow in row 9 and you'll see there are 8 cells with maximum digit 7. So one double digit is enforced. Can there be just 1 double digit? The arrow circles (bulbs) sum to 8+9+9=26, which is 2 short of the triangular number of 7, which is 28. So all digits 1 to7 and one double digit, even if it is only 1 is already 29. There have to be 2 double digits: 1 and 2. That's 4 of the 8 digits, summing to 2x(1+2)=6 and the other 4 must contribute 20 and be from 3 to 7. 3 to 7 sum to 25, so the 5 is skipped to have 20. 3+4+6+7=20 and with two 1s and two 2s you have 26 in 8 digits. That will spread out as 1+2+6=9, 1+3+4=8 and 2+7=9. 2 and 7 would be in the blue region in row 9, the cell of this blue region in row 6 would be the 1, as it's already in row 9 on the right side, in row 8 and 7 on the arrows. The double 2 finds its home in r8c8 in yellow and blue has its 5 in r8c5.

[@erik....]

I laughed when you were attacked by a fly. :D

[@illilillilifernhaven5277]

Before 56: the blue region can't pick up the yellow-or-eight cell because it already has an 8. And then, where does the 7 go in row 7. Can't go in the blue region, because the 67 go in the bottom row in the blue region because the bottom row of the yellow region goes into the neck of the blue region. Much simpler.

[@RichSmith77]

I wasn't quick finding it, but this was my eventual way through this stage. Far simpler, once you've seen it.

[@shahinulkhan7879]

What a lovely solve and puzzle. Very sadly that poor grey 3 did not get a song.

[@adipy8912]

1:06:07 I was like: Don't look at the clock, don't look at the clock! And of course you did it. Luckily you didn't start apologize upon apologize right after like you usually do.

[@MyriamTT]

1:01:01 The 1, Simon. And the 7 in row 6.

[@shaunbrowne9870]

40:00 The 7 only looks possible until you realize that every path to it that leaves room for nine cells in orange interferes with another arrow.

[@MyriamTT]

1:08:43 Yes, Simon. You have to do Sudoku now...

[@nyandmu]

Brand new sentence: "One of these is yellow, and one of these is eight"

[@groovinhooves]

Something about this puzzle (entirely to its creator's credit: do not mistake me) caused me to more than momentarily doubt just how committed to suduko I am (or wish to be) ^^;

[@Cloleman]

Is there anyone on Twitch or KZbin that shows themselves *CREATING* these puzzles? I'm simply baffled on how these are constructed so cleanly with logical solutions. I'd love to watch someone make some.

[@stephenbeck7222]

Zetamath and a couple other solvers will occasionally post videos of their setting. One of the featured setters here this week, Mark’s puzzle on Thursday maybe?, said they live-streamed the setting and got some help from their viewers.

[@Cloleman]

@@stephenbeck7222 will have to try and find them!

[@tessabrisac7423]

You can find a series of setting videos on CtC, all pretty interesting, one of which is an extraordinary “master class” by Clover.

[@tessabrisac7423]

The list is called “How to set a sudoku”, and already has 13 videos.

[@Cloleman]

@@tessabrisac7423 oh wow, very cool thank you. guess I hadn't gone far enough back in CTC yet!

[@striatedpardalote]

I don't know whether it has already been pointed out but from 33.00, r7c6 is either not blue because it is yellow or it is not blue because it is an 8 and blue already has 8.

[@oddbarnett]

"I'm being attacked by a fly and thats not reasonable" - New CTC merch?

[@LazerWulf]

"How To Make Time Pass More Quickly" - Set Playback speed to 2x, watch 1h20m video in 40m

[@giz-gizo]

I always watch simons videos at 2x speed and i am loving it😊

[@LazerWulf]

@@giz-gizo Even their shorter videos (with the exception of Wordle in a Minute) I have to watch in 2x because otherwise it just feels so slow now.

[@giz-gizo]

@@LazerWulf i know right! But its good thing we have double time to watch all their videos :)

[@TomHickey]

Moment of silence for the song-less 3 in the corner ;)

[@jonkess2768]

10:50 You literally said a minute ago that by having an 9 an 8 and their corrosponding arrows in the same region the rest of the region has to add up to 11. So you can immediatly say that does not work because the single remaining cell had to add up to 11.

[@jonkess2768]

So the only way to link up two arrows as you correctly said would be: With 2 2 cell arrows either 2 or 3 "rest squares" which have to add up to a minimum of 11. With 1 3 cell arrow and a 2 cell arrow exactly 2 "rest squares" which add up to a minimum of 11.

[@wossaaaat]

Woo, movie. Love it.

[@MyriamTT]

1:03:00 The 8, Simon, it's orange, cannot be yellow.

[@peterprade5587]

I got a different (non)solution: in the gray area, instead of 91862 i found 96812 and below that, the numbers in the yellow area are swapped: instead of 61/8 in my solution there are numbers 18/6. So it seems there are at least 2 solutions, which is kind of sad. edit: sad that i didn't see my mistake - absolutely lovely puzzle!

[@RichSmith77]

If I've followed your changes correctly (and I think you must have meant 96182 in grey, otherwise you have two 8s in c7), then you must also have swapped 8 and 6 in c4 (otherwise 8s and 6s repeat in rows 3 and 4). But the problem with this is that you end up with two 6s in the top blue region and two 8s in the purple region. The check function doesn't check the created irregular regions, so it still says "Yey! Looks good to me". There is only one correct solution, the one Simon found.

[@peterprade5587]

@@RichSmith77 you're absolutely right, I didn't think about the check function not testing all conditions. So i stand corrected!

[@tangrybird04]

So he said during the birthday shout out that Persephonie(probably spelled wrong) was one of his favorite names…wonder if that’s the name of his daughter🤔

[@Skamba]

Persephone

[@BigAsciiHappyStar]

Do the rules imply each region must contain exactly one arrow or is that do be deduced by the solver?

[@RichSmith77]

It appears it should be deduced. I mistakenly assumed there would be one arrow per region. I got completely stuck after half an hour. Watched Simon's solve for a hint, only for Simon to immediately consider the possibility of two arrows in a region, which I'd ignored. So I restarted without this assumption. 15 minutes later I reached just about the same position as before, and was still stuck. 😂.

[@icestormfr]

I didn't get, why there couldn't be two repeated digits. E.g. 126 + 125 in the red/green arrows, puting a blue one beside the 9, a blue 2 in the bottom row, a yellow 1&3 in the bottom right and a yellow 4 in R8C8, a blue 3 in R8, etc

[@RichSmith77]

You would have nowhere to put a 2 in yellow. Any digit repeated on the red/green arrows could only go in row 9 in yellow. That rules it out of rows 789 in blue. There's only one blue cell available above those three rows. Hence can only be one repeated digit, as only one place any such digit could go in blue.

[@silverghini2629]

Is there a chance to see how a setter builds a sudoku please?

[@donaldsnyder1543]

Poor 3 , no song for you today 😭

[@six_5000]

The attacking fly was the manifestation of my repeated shouting. The 6,7 in yellow have to be row 9 blue, which gets you a 6 on the red arrow But then again when does simon ever take the easy road

[@markbennet9058]

Logic @47 mins stunning

[@YourFavouriteDraugr]

He could've gotten that 1 by Sudoku if he knew how to count to nine. It was completely idiotic and unnecessary.

[@bruceh8043]

Finish in 1:00:20.

[@Raven-Creations]

When trying to see if a circle can reach an arrow, you do realise you can stop counting as soon as you reach 9 don't you? Continuing to count up to 12 gives you no additional insight. In many cases, you don't even need to count - most of us can easily identify up to 5 things without counting them. In a puzzle like this, you're generally trying to join the closest of any existing cells in a region to the furthest arrow cell. You know how many cells are already in the region, and you just need the taxicab distance to the furthest arrow cell, and the horizontal and vertical components are usually easy to enumerate without counting. As with every chaos puzzle I've watched you solve, you spent an inordinate amount of time considering arrangements that were clearly impossible, whether because they would require much too many cells, they'd require a cell that contains only options which are already in the region, or they would isolate cells. It seems to be because you're incapable of considering more than one rule at a time, unless you consciously decide to look for constraints imposed by multiple rules. I've noticed this trait in many multi-rule puzzles (e.g. the recent equal-sum/renban puzzle). I suspect it also explains why you place so many inappropriate pencil-marks. You consider a column and put in the column options, even though digits in the rows and/or boxes already resolve them. If you really are incapable, might I suggest that you develop techniques that avoid the problem? For instance, instead of highlighting the last three cells in a column and filling them with 368, highlight the cells, then deselect any which see a 3 by considering each of the rules in turn. Only after doing this do you press 3. Repeat for 6 and 8, and you've avoided the problem. Sure, it takes a few seconds longer, but it can save you several minutes in the long run, because you're not looking at a grid full of impossible options, which is frequently the cause of you getting stuck.

[@Ray-iu7hg]

The 9 in row 1 has to be in the 7 group, so the 7 group can't make it down to the arrow begining r7c6..

[@ryaneakins7269]

You're telling me there's a 9 arrow born in the purple?

[@thePatriotau]

Where does 6&7 go in row 9??? I was a little perplexed about that missing logic Simon.

[@MyriamTT]

Ignoring Sudoku Simon makes the video much longer than it could be.

[@CrazyIvanTR]

Hey Simon, in the videos as of late you've been missing a lot of stuff (not to complain really, since you can amazingly solve the puzzles without those). I just wanted to say that it might be time for a vacation from sudoku. I know you're enjoying solving them but ultimately too much of a good thing can become a bad thing 😅 If you're worried about leaving the channel without any content, I suggest pre-recording some videos. Though, I think everyone would be understanding if you took break for a week or two. I seriously hope you see this message and take it into consideration. I love watching your content and I wish all the best for you 😊

[@btestware]

Yes we worry about Simon too.

[@YourFavouriteDraugr]

You just wasted half an hour of everyone's life because you can't count to 9, and resorted to bifurcating what is otherwise easily deducible by logic. Horrendous solve.

[@4evafcn]

1h 19 min is quck?

[@pedrobluis]

@Simon did you know that: "In mathematics, the four color theorem, or the four color map theorem, states that no more than four colors are required to color the regions of any map so that no two adjacent regions have the same color. " en.m.wikipedia.org/wiki/Four_color_theorem

[@CaptianKatsura]

This only works if you know the borders in advance, though. To make use of this in a solve would require constantly changing colors, which would be annoying.

[@pedrobluis]

@@CaptianKatsura well, we see Simon often change the colors so no big deal there