A New Type Of Sudoku Line!

[@lake1525]

Hey Simon! Thanks for another excellent feature and solve :) - I had a lot of fun setting this one, it was actually initially made for ThePedallingPianist, and I'm very grateful he recommended this! A slightly cheeky thing I did with this one - I made the lines different colours, and my intended solve path required looking at the lines in the same order as the colours of the rainbow, and you followed it perfectly! Really made my evening with that, thank you

[@longwaytotipperary]

What a delightful puzzle!!

[@SilvrSavior]

I guess the sequel puzzle could be Sum Differences with Region Sum Lines (RSLs) and Region Difference Lines (RDLs). Then a finisher could be Adding Differences, and I don't know how it could be constructed, but you could have grey lines that the solver needs to figure out if it is a RSL or a RDL.

[@davidrattner9]

Fabulous from you!!! Loved everything about it!!

[@davidrattner9]

​@longwaytotipperary very delightful indeed. 💜🩵

[@MedusaMrigesh]

Phenomenal puzzle, enjoyed it tremendously! Took me a while but it went smoothly (except for once towards the end where I had to check with the video because I missed the sudoku around 8 in column 3)

[@ubk-qm4rz]

When I saw "sum of adjacent segments" I was thinking that somehow I would be adding two adjacent segments together. Did others find the rules unclear?

[@aleksandarmahdik377]

Oh, yes.

[@Jack-sy6di]

Yes - I'm back here to watch the video and get some clarification! No idea what this rule means

[@mikebell9759]

Yes, it is grammatically confusing

[@Jack-sy6di]

After watching the video - a better phrasing would be: "For each line, the difference between the sums of any two adjacent segments is the same". A big problem with the original phrasing is that the word "sum" is singular

[@mikebell9759]

And i feel like the fact that numbers can/cannot reverse direction (i dont know yet if they can or not) is unclear because id say the difference would be positive or negative

[@martysears]

Loved this puzzle when it first came out - was a pleasure to help test it ! Really enjoyed Stu's prompt to set a puzzle with a regular line type but with the rule applying to region sums rather than individual cells. Of all the puzzles made for this prompt, this was by far my favourite (maybe I am biased though because it contains same differences 😉) Thoroughly deserved feature, and was great seeing Simon thoroughly nail all the intended logic in that special way Simon tends to do

[@davidrattner9]

Loved that you tested this. Always respect for what you have to say about other setters and there amazing abilities!!

[@juriaanpeet3173]

Man, took me like 25 mins to get that the difference could be 0...was convinced the puzzle was broken for a while there... Anyway solved in 65m31s.

[@Kairamek]

This is why I'm not shocked that the mathematical concept of zero wasn't codified until the 7th century. We know it exists and keep forgetting it's an option.

[@jimi02468]

If the difference is zero it means that there isn't really any difference to begin with. So that explains the confusion. I didn't get it either

[@dean244]

So what Simon keeps telling us, when he brings up the secret, without actually saying it, is that Douglas Adams was off by 3.

[@janeflett4971]

Love it 🤣

[@Kraxxus-vonDalaran]

To be unnecessarily precise: the written rule says : There exists a line with the difference property, not: each line has the difference property.

[@Manigo1743]

I actually read that as a negative constraint thinking that only one line may have the difference property. Badly worded rule.

[@robertosecco983]

@@Manigo1743 Me too. I was really confused.

[@puritan745]

Not really unnecessary, that confused me for a minute or two until I just decided I couldn't solve it if I had to figure out which line was THE line.

[@MichalMarsalek]

Yes it's a bit confusing - why does it say "one of these lines" and not "each of these lines"....

[@joostvanrens]

​@@MichalMarsalekbecause "each of these lines" could mean all lines have the same difference between boxes

[@inspiringsand123]

Rules: 04:22 Let's Get Cracking: 06:28 Simon's time: 57m01s Puzzle Solved: 1:03:29 What about this video's Top Tier Simarkisms?! The Secret: 8x (09:16, 09:28, 09:31, 09:31, 09:31, 09:42, 15:27, 33:27) Bobbins: 2x (37:10, 46:32) Three In the Corner: 2x (45:33, 50:15) And how about this video's Simarkisms?! Ah: 14x (24:29, 25:02, 26:55, 26:59, 27:08, 29:52, 36:44, 42:34, 48:09, 56:00, 58:13, 1:00:27, 1:01:05, 1:02:50) Sorry: 10x (09:00, 10:53, 16:13, 17:36, 25:13, 25:18, 34:54, 36:59, 44:17, 54:16) Hang On: 9x (15:25, 15:25, 16:06, 25:04, 25:59, 29:49, 29:52, 29:52, 52:41) In Fact: 7x (04:50, 40:34, 42:20, 47:49, 48:35, 56:14, 1:00:05) Clever: 5x (02:02, 1:03:20, 1:03:51, 1:03:51, 1:04:24) By Sudoku: 5x (36:06, 45:38, 56:36, 1:02:53) Beautiful: 4x (30:01, 49:31, 1:01:43, 1:04:21) Brilliant: 4x (03:11, 04:04, 04:08, 31:34) Surely: 3x (09:19, 1:00:31, 1:00:51) Nature: 3x (42:20, 49:55, 1:04:16) Cake!: 3x (03:15, 03:31, 04:10) The Answer is: 2x (35:08, 45:21) Approachable: 2x (02:32, 02:34) Bizarre: 2x (31:31, 31:34) Obviously: 2x (48:49, 57:41) Pencil Mark/mark: 2x (32:00, 47:19) Goodness: 1x (1:03:33) In the Spotlight: 1x (50:17) Lovely: 1x (02:21) Ridiculous: 1x (02:02) Gorgeous: 1x (44:43) Shouting: 1x (03:26) Epiphany: 1x (1:04:01) Spider-Sense: 1x (20:26) Wow: 1x (1:03:39) What Does This Mean?: 1x (31:39) That's Huge: 1x (1:01:30) Weird: 1x (17:54) Most popular number(>9), digit and colour this video: Twelve (26 mentions) Four (76 mentions) Purple (19 mentions) Antithesis Battles: Low (8) - High (3) Even (15) - Odd (14) Lower (10) - Higher (8) Column (12) - Row (7) 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!

[@bluerizlagirl]

If ThePedallingPianist recommends a puzzle, you know it's got to be done! Some fantastic logic there. It's a really elegant twist on the Region Sum Lines we've all come to love! I'm sure Simon has done a puzzle before with cages whose totals followed a consecutive sequence, but that's the nearest thing I've seen to this before.

[@57thorns]

49:33 Simon filling in row 5 column 7 before row 5 column 4 is just such a Simon thing. Plenty of opportunities to clear up pencil marks and make the easy deductions, but always looking for the next shiny one instead.

[@57thorns]

56:49 the difference is one, but no, we are _not_ resolving row 4 column 5 immediately, there are more complex things to deduce first.

[@57thorns]

1:01:02 And now we look at the column, please?

[@someblokeontheinternet]

Grr, I figured the orange segments in boxes 7 and 9 needed to be the same sum, but seemingly couldn't - I didn't consider a difference of zero along the line

[@francolerud]

@@someblokeontheinternet I spent about 20 minutes staring at the puzzle until I figured that out. I had an alternate option for the difference on the orange line that resulted in box 8 adding to more than 45.

[@shaunbrowne9870]

That zero difference is evil. I was sitting here with my first deduction being "If red in boxes 7 & 9 are the same then orange in those boxes are the same, which is CLEARLY impossible because it travels through an even number of boxes to get there, so red must continue decreasing at least that far," and when you proved that they were the same I was like "Simon, what did you break?"

[@Paolo_De_Leva]

Unquestionably a *cosmic class* construction❗ I am 100% sure it will be included in the next *CTC Cosmic Hits* book. Drastically simple and at the same time radically innovative ruleset. Stratospherically elegant and fairly challenging logic for each of the lines. I am impressed. Thank you *Lake* for designing this memorable beauty. Thank you *ThePedallingPianist,* for recommending this. Thank you *Simon* for featuring it. 👏👏👏👏👏👏👏👏👏👏👏👏👏👏

[@A_CC_K]

After a stressful day, a long video is what is needed, it makes everything better. Brilliant puzzle

[@spin-rg9ib]

@40:15 the easiest way i found to deduce the line totals. after you determine the steps(up or down) the lines takes between each region. it makes it that R1C5:6 line is equal to R3C7. and you know the total is single digits because the 123 is already used in box 2 leaves 4 and 5 the only digits that sum to a single digit. Edit: just realized that it was possible for it to go up again between box 3 to box 2. i guess its true what they say luck beats skill

[@daniellerodgers6493]

Watching this channel is the nerdiest thing I do 🤓 😊

[@whirledpeas5717]

I would agree with but I also watched the world jigsaw puzzle championships a couple of weeks ago! 😊

[@kf7872]

Hmm, is watching this more nerdy than watching the European tram driver competition?

[@daniellerodgers6493]

@@whirledpeas5717 oh man I just realized I watch Karen puzzles sometimes and I do watch those championships too 😅 this is probably still #1

[@daniellerodgers6493]

@@kf7872well I just checked it out and…. Whoa that one takes the cake 😂

[@puritan745]

Thank you for bringing this puzzle to us Simon, I Loved it!!

[@chocolateboy300]

I finished in 69:30 minutes. This has been one of the most fun times I have had in a puzzle. The break-in with the big red line was excellent. I remember doing another puzzle that also relied on this effect of areas getting smaller in the next box, so I think that helped me understand this one. I, initially, ruled out everything and put a 4 into box 4, with the orange line having 8 on the left and 16 on the right. However, this broke and then I spotted the troll solution of having no difference. I was so excited to see that. I think my favorite part was proving that 4 and 5 couldn't go into r3c6, due to the differences being too big for the two celled green line to go up from the four celled line. This forced the two celled line to be 9, but it breaks because a 123 already exist on the yellow line and I started with a 4/5. No combination works. Everything felt so deliberate in this puzzle. It is an incredible work of construction. This has to be one of my favorites. Great Puzzle!

[@jussikuusela7345]

23:00 I'm afraid that there is a veeery tricky solution to the orange line, that involves adjacent segments having an equal difference, only I'm pencilmarking something wrong... so, now I must watch the video further to see if Simon indeed comes up with the same hypothesis. EDIT: Apparently Simon reached the same conclusion as I did.

[@titusadduxas]

1:42:23 - It took me the best part of an hour to break in but I loved every minute of it. Another gorgeous puzzle.

[@stevieinselby]

Right from the very start of the puzzle, I had a suspicion that at least one of the lines would have a difference of zero, on the basis that that is the kind of sneaky trick that constructors like to include 😉 so I was ready for it when it came! I solved the puzzle in under 30 minutes although watching the video back, I think there were a couple of places where I jumped to conclusions that were not justified but turned out to be right, so I can't really claim that as a solve time 😢

[@sneakyghoti]

I haven't even finished the puzzle, and I am in love with this ruleset. Absolutely wonderful puzzle.

[@andrewcook4873]

This was a really fun puzzle. The interaction between the red and orange line stumped me for a while. But once you get some insight on the lines it rewards you quite generously making it really fun to do.

[@penningmeestercgkdelft9159]

30:02 It is beautiful to see Simon react on the beauty of r6c7 and the restriction it yields! Was shouting for some time ;-)

[@kavitajagannathan6329]

I love how in a region difference line, the orange/yellow line became the same as a region sum line😂

[@mwoody_]

Captain Jack Magpie: "why is the sudoku never done?!"

[@RedBarchetta2019]

Building a little excel sheet proved that that digit not on the line in box 4 had to be a 4. However - finding out how that worked befuddled me as I also did not consider a difference of NYET - NINE - ZED - ZERO!! Well played.

[@bessieish2077]

0 in german is null. No in german is nein.

[@longwaytotipperary]

I thoroughly enjoyed taking a stroll in logic land!!

[@davidrattner9]

Strolls are so relaxing and enjoyable. Was it a "Wednesday stroll" instead of a " Sunday stroll" ? 😁😀 We can go on a stroll with Simon all the time.

[@longwaytotipperary]

@@davidrattner9 yes!! 💜💙🧡

[@petermawhorter9016]

Tricky but fun puzzle for me. Slowly savored it in 03:11:40. I got tripped up on the zero difference too, which is extra sad because I noted it during my thought process, but then immediately forgot about it. Gotta put in more reps to up my mental option-juggling capacity. I was considering between x/2x/3x/2x/x and x/2x/3x/4x/3x for the missing parts on the red line, and trying to enumerate that over 4/5/6, so even though I noted the zero possibility for the orange line, I didn't have room to maintain awareness of it, and tried to make orange in box 9 sum to 16.

[@jonathanbarz9898]

for me, i marked the difference between adjacent segments on the red line as X, and then defined the different regions within a box NOT including red line as "X, 2X, 3X, etc." until I could isolate that X was 4 using deductive reasoning! whether box 9 was 4X or 2X led to the same conclusions about the yellow line and that was the major break in

[@davidhughes7174]

Beautiful puzzle and solve. Thanks again simoy

[@emilywilliams3237]

This was a very interesting video. I read the rules a few times to be sure that zero was an acceptable difference, and when I assured myself that it was, I had a feeling that there would be a line that could have a difference of zero - and that it would not be a blue line! It was really interesting to watch you work out how the big red line worked. Thanks for the video!

[@EelcoWind]

I like this new ruleset, it's different from what we're used to! (I'll see myself out)

[@LednacekZ]

32:53 for me. the hardest part was proving the orange line. spent 20 minutes on that.

[@piarittersporn]

What a brilliant puzzle. To define the red line and the yelllow lines was not very difficult, but it took me quite a long time for the next lines.

[@calculatrgay]

Thats got to be the best sudoku I've ever seen

[@btuftin]

Took me 2 hours. Spotted the opening fairly quickly, then struggled with thinking the puzzle was immediately broken, and then had a lot of trouble completing the pink and blue lines due to just doing sudoku wrong multiple times. :D

[@Michaelzehr]

This was surprisingly fun for how long it took me. As is often the case I made early progress and got to about where Simon was at about 57 minutes (took me closer to 90 minutes to get that far) and then failed to Sudoku properly. Very interesting, though feel chagrined I needed a hint near the end.

[@ericpraline1302]

Interesting, thanks, sure I missed a more elegant solution path which no doubt Simon found.

[@vw8796g35]

Great solve Simon!! Definitly on this one a bit more sudoku would have make you solve it faster 😀

[@johnellis7327]

Hearing Beckley, WV blew my mind. Happy birthday Kaden from Princeton, WV! (About 30 minutes away)

[@craigyoung8008]

I was ready and waiting for this 28:11 stage of the puzzle. Because right from the start, I decided that if there wasn't at least one line with a difference of 0, I wouldn't like the puzzle. 😁 Both blue and orange were candidates.

[@bobbie0976]

Little over an hour. I spotted the break in quickly, but still took a bit to figure it out. Lots of fun math!

[@griof]

Awesome deduction of the first 4. I wrote down a system of inequations translating red and orange restrictions into numbers.

[@rockyshi6714]

It took me 95:43 to solve this puzzle. The red and orange lines are fine. I deducted the difference 4 and 0 quickly. I can't calculate the sum of segment as fast as Simon does. But it is easier to only think about the difference. I marked r6c1 as A and marked difference 2A, 3A in other grids. I was really excited when I found the difference of orange line had to be 0. Then the biggest problem is the cyan line. I stuck when I know r4c4 is 6 or 8 , r3c5 is 7, r4c6+r5c6 is 6 and r5c7 is 4 or 5. Yes, you can see I forgot to remove 4 from r5c7! It is not valid any more after I got 7 in r3c5. That wasted me a lot of time to find other sudoku solution. Finally I noticed this and got the solution smoothly.

[@kimspence-jones4765]

Well, it took me 132 minutes, but I got there. I loved the absolute joy when I reached the ‘now it’s just sudoku’ moment!

[@dustinkeier9176]

@Simon, hands down the funniest moment I have experienced watching your videos, had me laughing out loud for a bit longer than I care to admit. "Here we go, here we go .... no we don't." 😂😂😂😂❤❤❤❤

[@scarletmanuka6170]

Really loved this puzzle! A nice little bit of maths for the break-in with the red and orange lines working together, and then being led through the rest of the deductions by alternately considering the other lines and everyone's fickle friend, sudoku :)

[@martinepstein9826]

49:35 "Knowing these are of different parity is telling us that digit!" Actually, if r3c5 and r4c4 were the same parity you could still reach the same conclusion! On any line, the parity of every other segment is the same.

[@gombospatrik]

I solved it in 75 minutes but I couldn't do it without notepad, typing down some nice equations.xD That was necessary to start, and even in the ending there were some interesting stuck moments. I loved this sudoku, thank you.

[@Orenotter]

That puzzle was hard, my oh my! The minutes, they just seemed to fly. You're a family delight On a late Wednesday night But I solved ere the others came by.

[@jaredwonnacott9732]

Got the difference could be 0 early on, promptly forgot it, then went on to prove the puzzle was broken like 3 different times before remembering what I'd decided when I'd started that line.

[@roccov3614]

27:50 So pleased that I figured that out. A real AHA! moment. Stil haven't finished the puzzle. I don't know if I will. It's a bit too frustrating.

[@angec9908]

The stream was awesome. Thanks.

[@jonathanallan5007]

Missed the opportunity to say "x is two x, therefore x is zero".

[@Coyotek4]

37:59 ... I missed Simon's logic involving the 8 in column 3 and resorted to some torturous logic involving the purple line; other than that, I felt I did well on this one. Nice puzzle!

[@srwapo]

119:58. I beat 2 hours! I started off relatively fast, then got stuck with the purple and green line. I screwed up placing at 8 in column 3 (didn't see the 8 in row 6 eliminating it from r6c3) and had to look at the video to see that.

[@PathOfShrines]

Really neat rule. 51:01

[@Lesterberne]

i had to pull up a pen and paper to write the math for this xD

[@jeffreyrosas1784]

Is it “Lake” or “Laake?” On Logic Masters this puzzle is credited to “Laake.” I remember one of my favorites, “My Strange Zebra,” was set by the same puzzler.

[@lake1525]

Hah! On LMD it's Laake, but I go by Lake. The reason for that is I made the Lake account on LMD first, but then I forgot the password and had no way to recover it as I didn't have an email associated with it. I also really enjoy the zebra puzzle, that was my first feature about a year ago :) Glad you liked it

[@jeffreyrosas1784]

@@lake1525 watching Simon solve your zebra inspired me to set my first sudoku ever, also featured on CTC in February: kzbin.info/www/bejne/iZ7MpZ53mtp0ntEsi=PtYD2tOgXMF_XSCh

[@lake1525]

@@jeffreyrosas1784 oh thats incredible!! What video was it?

[@jeffreyrosas1784]

@@lake1525 kzbin.info/www/bejne/iZ7MpZ53mtp0ntEsi=3zb2sdYe5z4HPJDU. I gave you a shout out in one of my comments.

[@jeffreyrosas1784]

@@lake1525 kzbin.info/aero/PLZ3w6VRukegWuPkpIJG_UD80xtDD09rBX&si=Nf8EXJD8SdYoqO4K

[@roccov3614]

I think you're wasting time switching back and forth between the red line and the remaining squares. If you find a valid sequence with the remaining squares the red line segments must also be a valid sequence.

[@CaptainSpock1701]

56:12 - I have never shouted so loud at the PC monitor that "That's a seven" after Simon went from the difference is one, therefore this is a five, this adds up to a six... And then just stopped short of the seven!

[@armengabriel]

F-word avoided at 49:28? :D

[@WorldsPhamous]

How do we know the 2 cells off the red line in box 7 are twice the cell in box 4 and the four cells in box 8 are double that???

[@RichSmith77]

The answer to the first part is given at 10:25 in the video: The red line differences cannot go -x, +x, since we would get back to the starting value of 45, and the sum of the red line in box 7 cannot be 45 as it doesn't occupy all nine cells in box 7. The answer to the second part is given at 12:40: If the differences along the red line went -x, -x, +x then the sum on the red line in box 8 would be the same as the sum on the red line in box 2. That means the sum of the digits OFF the red line in boxes 2 and 8 would be the same. But in box 8 that's four cells with a minimum sum of 1+2+3+4=10, and in box 2 it's a single cell with a maximum of 9, so they cannot be the same. Therefore the differences along the red line have to be decreasing by the same difference each time, so -x, -x, -x. If the sums on the red line are decreasing by x each time, then the sums of the digits OFF the red line in each box have to be increasing by x each time. E.g. if the difference along the red line is 4, the red line segments go from 45 to 41 to 37 to 33, and the sum of the digits OFF the red line go (0), 4, 8, 12.

[@yashmehta9299]

Sub hour! Definitely quite easy for a 4-star, given I’m basically a noob at sudokus

[@aartbluestoke3352]

20:00 so close - I noticed that the orange line can't have the same number in box 7 and 9, forcing the red line to go down, not up ... then Simon 27:00 came to the conclusion (except when the difference is 0) ..

[@5t757]

39:30, took me a while to get past a few choke points but always love innovative rules.

[@TFMurphy]

49:21 It's actually even more general than that. With a "Same Difference Line", any cell that is an even number of cells away along the line will have the same parity, because the difference two spaces away on a line with difference x will either be the same number (with the same parity), or have a difference of 2x (and an even difference always preserves parity). This naturally follows for the Region Difference Line, just with Region Sums instead of individual cells. So as soon as we see that only odd digits are in r3c5, we know that only odd digits can be in -r5c6- r5c7, regardless of what the line difference is. *EDIT:* Fixed messed up cell notaion -- apologies for any confusion.

[@al0ttafagina]

I'm not sure I am following this logic. Are you claiming that r4c6 and r5c6 could never have been a 24-pair, disregarding the rest of the grid? None of the lines in the completed grid are folowing the pattern you are describing

[@TFMurphy]

@@al0ttafagina Ugh... sorry for the confusion. The logic is sound, but I messed up the cell notation. I meant to refer to the cells on the blue line in boxes 2 and 6, which are two regions that are an even number of steps apart along the line. The main point was that you don't need to know the parity of the regions in box 5 in order to determine that the parity of the box 2 and 6 regions are the same; unfortunately, my mistake muddied that insight, so that's my fault. Another way to think about this property is to observe how the parity of region sums change along a line. If the line has a difference that is even, then the parity of each adjacent region sum will be the same: either all evens, or all odds. If the line has an odd-parity difference, then the region sum parity will alternate with each adjacent region. In both cases though, even before you know the nature of the line's difference, it's clear that every other region sum will share the same parity, whether it alternates between adjacent regions or stays the same.

[@al0ttafagina]

@@TFMurphy Gotcha! Thanks for clarifying

[@soylerava]

46:21 here we go, here we go! no, we don’t… here we went… there we went and there we failed lmao😭😭

[@Gonzalo_Garcia_]

37:09 for me. Gosh I struggled with this one, what a tough puzzle!

[@eefaaf]

9:40 You don't need to know the 'secret' to see that the difference between box 1 and 4 will be digit in the single cell the red line doesn't cover in box 4. And so on for the 'untouched' cells in the next boxes. Edit: So, I hadn't thought of the sum being able to go up and down. Interestingly, as box 7 and 9 are filled by red and yellow in the same way, if the sum for red goes down and then up between those boxes, the value of the sums of both lines in those boxes will stay the same, But that only will work for yellow, that passes through one extra box, if the difference between the box sums is zero. (and if red's total keeps going down, then the difference for yellow will be either double or two thirds of red's_

[@MathsTutoringRocks]

Hello!

[@roccov3614]

29:00 The way I put it is, you have to take 3 steps and end where you start but you can only get back to where you start with an even number of steps.

[@therealedvaize]

The ruleset is kind of weirdly stated. The "on one of these lines" part makes me think that the rule only applies to one of the lines.

[@lake1525]

Yeah, fair enough. I could have maybe done it better, but the person who I made it for understood

[@domanski123442]

😊

[@RecreationallyCynical]

38:40 for me. Lovely Marty-Sears-esque break-in.

[@lake1525]

Marty's a great friend and I love his break-ins so Im really happy that you think this :)

[@mikaylajennel6170]

Has simon ever NOT told us the secret in any of these videos? (Question only applies to his favorite people)

[@bait6652]

Interesting without the given9 there's like 8-12 other solutions

[@bait6652]

Onlu confusion i had was if it was strict pos/neg diff or abs(diff). BUT the puzzle itself tells you thru B789...unfortunately even tho i knew about it, when i cam upon the error i thoughr i broke the puzzle and couldnt figure out of it (ie the diff could osc +/- and was abs diff)

[@MaierFlorian]

41:20 - Simon missed a point here, didn't he? You could go 4 - 8 - 12? So r4c7 isn't forced to be a 9... Edit: he missed it, but this won't work as you need either 8 or 16 now in Box 2 again, first is ruled out by the 123-triple, second is ruled out by the given 9.

[@BryanLu0]

Solved in 38:18 ! The rules are a bit confusing...

[@СеменФадеев-ч1и]

I don't understand rules. Each sum of adjacent has the same difference on one of these lines or on each of these lines

[@zhoppa]

every line obey this rule basically

[@berendharmsen]

Try this: a coloured line crosses into another box. The sum of the values of the coloured line in box A will have a value, say '19'. The part of the line in the next box B will also have a sum, say '23'. The difference is 5. If the line then continues from B to box C you now know that the sum of the cells for the part of the line in C differs from 23 by 5, so either 28 or 18. Coloured lines can end up in a box twice, but that is ignored. And that apparently helps you solve the puzzle 🙂

[@j.wellens5660]

@@zhoppa but that's not what the rules say - They state that ONE of these lines obey this rule.

[@zhoppa]

@@j.wellens5660 true, perhaps a translation error

[@goldcakes]

I found it so confusing listening to Simon use the values on the red line to justify the size of digits not on the red line. E.g. saying box 9 red line equals 37, if going up by 4 to 41 then the 3 squares in box 6 need to add up to 4. Rather than looking at the cells not on the line and seeing box 9 sums to 8, and box 6 has an 8 in it's "empty" squares meaning it has to go up(line goes down). I love it, but very confusing.

[@Kairamek]

The green segments are the same, but the yellow line breaks when trying to math the difference. So that means... Call me Brahmagupta cause I've discovered zero!

[@charlesh.1643]

Sorry! Watching Simon solving this...broke my brain.

[@TurquoizeGoldscraper]

35:45 for me.

[@PVempati]

34:19 pretty good

[@FrancisFjordCupola]

The secret of sudoku is 45. The answer to life, the universe, everything is 42. Explain the difference.

[@bernierossi8062]

Sudoku is more important than life by a count of 3

[@PleasantDoorknob]

30 mins in and I’m totally lost. I understood the rules to mean only one line was a same difference line and thus we could ignore the others. Simon first looked at the red line but then starts focusing on the orange line as if it is key to solving. Why? Why does the orange line also need to obey the same difference rule?

[@RichSmith77]

Because the interpretation that the rule only applies to one of the lines is clearly a nonsensical interpretation. Obviously the rule applies to every line, it's just explaining how the rule works in relation to any one line. How could it possibly be a working puzzle if the rule only applied to one line, and we don't even know which one? It could be that short three-cell purple line. How could that possibly be enough information to uniquely solve the puzzle?

[@PleasantDoorknob]

@@RichSmith77lmao sorry to have triggered you. The rule says: “Each sum of adjacent segments on one of these lines has the same difference.” It clearly says on “one” of the lines, not all of the lines or each line. It logically follows that the implication of this phrasing is that only one line obeys this rule. The rule is very poorly written.

[@nicholasiverson9784]

I dub this line, a Redi line.

[@titirenee]

Titi's Time: 53:34

[@СеменФадеев-ч1и]

23:52 Simon forgot that only one line was difference sum regions line. Other lines seem to not exist. Am I right?

[@57thorns]

They are all difference sum lines.

[@RichSmith77]

That would be one interpretation of the wording. Fortunately, it's obviously a nonsensical interpretation that we can immediately dismiss, forcing us to find the correct interpretation. The same rule applies to each line. Take any one of the lines, and the rule is that the adjacent regional sums along this one line have the same difference.

[@vasilyok_i_mopsyonok]

Голос просто🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻🎻

[@iceberg54321]

Figured it had to be 4, skipped 20 minutes.