Thank you so much for the feature, and a wonderful solve! Sorry for keeping you up so late 😅This is almost certainly my hardest puzzle, and is the culmination of 3+ years of setting, solving, and of course watching CTC constantly. Ever since discovering CTC about 4 years ago, my life has permanently changed for the better. I truly can't thank you and Mark enough for the endless positivity and growth you have provided me. [Some potential spoilers ahead] I may make a video solution of this puzzle at some point, but for now I'll make a few brief comments: 1) The break-in becomes noticeably easier if you consider R1C3 earlier (and then its geometric/renban effects). I did indeed craft the break-in around "what happens if 3 is in the corner," and the second part of that was "what happens if two 3s are close to each other?" 2) The end becomes noticeably easier by focusing on the 9 in R7C6. If it's gray, it breaks both the king sum and the bishop sum, leaving only 1 chess sum available for R8C5. 3) Although it is easy to try and whittle possibilities down (and there is really nothing wrong with this approach), I intended for most if not all of the deductions to be made with a min/max approach. One example is when you were considering the yellow 9 seeing 7 different cells. That is indeed impossible because those 7 cells have a minimum sum of 28 yet 9*3=27. Granted, asking the right questions is not easy here, but I tried my best to always have a strategic way for every step. This is just a little insight into my intentions. All that said, I enjoyed your solve immensely, and this puzzle is NOT easy---so many many kudos to you Simon. Thanks again for being such an important part of my life all these years. Cheers!
Mind blowing from you!! Huge respect for how you set and this is just out of this world!! Thank you for your 3 points above and insight into your brilliant mind. Would love to see a video solution of this or how you set it!! 🙂
Regarding point 2: You can know straight away that king's move isn't included for this sum, simply because all the 9's available to gray are always touching the 8, and one of them has to be taken!
@@fdlatyt that is certainly what i spotted in the end. somehow simon gets too focused on a specific that he forgets the same rules apply to other things as well. i think its a sort of tunnel vision for him
Came here to say this. Both the 9 being a kings move and bishop's move away from the 8 in the bottom gray and how he's looking for a 6/2 kings move pair in the bottom gray completely forgetting there's a 4 in the king's move as well.
A 15-minute Simon puzzle: takes me 5 minutes. A 30-minute Simon puzzle: takes me 30 minutes. A 45-minute Simon puzzle: takes me 2 hours. A 2-hour Simon puzzle: I cannot risk losing my home, my job and my family by devoting the years necessary to attempt this.
I really enjoy being a backseat sudoku solver. "Sort the 1 and 3 in the blue region and it places 1 in yellow, Simon" at a puzzle I could never in a million years solve on my own lol!
i know right! and sometimes he solves them in the most complex way (ex: the purple 4 at the end was purple simply because the other 4 was grey, but he did that in such a complicated way ahaha). but tbh, noticing this stuff makes me better a sudoku in general cause i can rely on simon to be right in the end
Today is my birthday Simon! I turn 23. Nobody in my life would probably send you message about my birthday since they don't understand why I watch these, but I do greatly enjoy watching every day. -Will
it’s been insanely hot and dry here in Brazil due to some wildfires, so to be able to solve (or at least watch Simon solve 😂) some sudoku in the comfort of my room with some AC and a nice cup of water is a real privilege. thanks for making all our days better you two!
I think there was a logical error here. At 1:15:19 Simon hypothetically colours R1C8 grey in order to prove that R2C7 is purple, but then having proved that R2C7 is not purple, he forgets to un-grey R1C8. I wonder how you can actually prove that R1C8 is grey cause that's where I got stuck...!
Yeah that's true. The way I saw is to go for the logic of the green region first, which also lets you place the 3 of the red region into R6C7. Orange has to extend, which makes it go to R5C8. Afterwards you look at the chess moves of R3C7. It can't be in orange because R5C9 would be the only diagonal box in its region and kings move doesn't work. So it has to be grey which limits the option to bishop and knights move and the 2/7 pair at the top in R1C6 and R1C8 is the only way to make that happen.
1:21:59 I think the deductions around knights moves here proves it. Once R3C7 is 9 and isn't king, you need to look at the possible digits. R1C6 is definitely grey, R4C9 is not grey or you trap the blue region. 134 have been used in grey, so the only option left is 27. If R1C6 is 2 then R1C8 is grey and 7, as R5C8 isn't 7. If R1C6 is 7 then R1C8 is 2 and R5C8 can't be 2. Sorry, that looks like I've smashed my fist into a keyboard but I think the logic makes sense?
I think the simplest way to see it is to ask whether r1c9 can be grey. If it is, then r1c8 must also be grey, to connect the grey region together. If that’s true, then you can’t put a 4 onto the renban, so r1c9 must be a non-grey 4
@@leftysheppeyyeah i found something similar. the 9 has to take 2|7 by knight's moves (those are the smallest digits left in grey). putting a 2 in r5c8 creates a 1|3 pair in r5c67, which forces a 4 into r5c9 and that cuts off the blue region (which has to take the 4 in r1 no matter what). therefore the grey 9 is looking at r1c6 and r1c8, pushing 4 into c9.
1:56:43 I think a beautiful piece of logic for solving that part is thinking about digits in the immediate diagonals to cells with 2 chess sums constraints: For example, the 9 is in the upper-right diagonal to the grey 8 cell that has 2 chess sums constraints, but that position belongs both to the set of cells reached by a Bishop move AND to the set of cells reached by a King's move from the 8, which means it cannot possibly belong to the grey area (otherwise it'd be impossible to satisfy 2 chess sum constraints), therefore it's purple. The same is true for the 8 in the upper-left.
1:52:10 You just proved that 9 can't be grey. It's both a king's and a bishop's move away. The 9 being purple also makes the 7 and the 5 next to it purple, so grey has to get to the other 5. Purple can't flow around the right side of the grey 8 as there wouldn't be any moves available, as you showed. So it has to flow around the top to reach the leftmost 4, and the grey 5 connects via the bottom row up to the 4 and goes on through to the 1, as purple can't reach it. The colour of the 3 and the 9 in row 8 are resolved by sudoku.
As someone who doesnt like word games, I do really enjoy the crossword videos every week. As you explaining the logic behind the clues is very facinating
started doing this sudoku w/o looking at the video length, immediately stopped w/ no idea what to start with, and immediately understood that it won't be easy with the 2hr video
Right at the end, between grey and purple, the 9 in r7c6 breaks the knight and the king move so must be purple. At some point you ruled it out of satisfying the king move but then didnt count it in the bishop move.
Yep (started at 1:51:50), Simon _immediately_ noted that the 9 broke the king's move, while at the same time _not_ noticing that it also broke the bishop's move. It was a screen-shouting moment. :)
One piece of logic late on - Simon, you looked exactly in the right place - R7C6(=9), but moved on too quickly to realise. If R7C6 is grey it breaks both the kings move and bishops move sums for R8C5. I am sure if you did two or three of these that would be an automatic deduction. You got (a version) of it eventually.
This channel is so cool! I'd never find puzzles like this otherwise, and I'd certainly never attempt them, but with a couple assists from Simon I just had a lovely Sunday evening working through this. Thanks for everything you do
I think the much simpler way of solving the bottom of the grid is to ask where grey gets it's 9. No matter where it is, it's a kings move away, and so the two constraints must be knights and bishops moves. To avoid the grey 9 falling on the bishops diagonal, it must be r8c4. Everything else collapses from there without having to pick at digits. Purple takes up the whole top row, the 2 constraints for the grey 8 fills out the bottom row from the only places that can fulfill the bishop and knights moves and then it's just basic sudoku for the rest.
At 1:16:37, isn't that deduction based on a cell that was colored on the assumption that r2c7 is purple? Why can't r1c8 hold that number at that point?
I think you can get to that digit with a few extra steps by deducing that r1 c9 must not be gray (call it blue), and that blue takes one of the pair in r1c8 and r1c9 and must pass through the other half of the x-wing in r5c8 and r5c9 to get to 9 cells, forcing the value of r5c8, which in turn forces r1c9
I just paused the video at this point to see if anyone had caught this, and yours was the first comment I saw. I agree, he got a little lucky. He should have uncoloured r1c8, and that might have been the 4 in row 1.
The way I eventually resolved the placement of 4 in row 1 was to see that the five cell renban lower down c8 had to have a 4 on it, since its top digit is 1,2,3 or 4, and then the 4 has to appear in c8. So r1c8 cannot be 4. That by itself doesn't force r1c8 to be grey, but the x-wing on 4s in rows 1 and 5 is resolved with 4 in r5c8, and the only way then to satisfy the 2 chess sum clue in r3c7 requires a 27 pair a knights move away in grey in row 1, making r1c8 grey. (I think I also concluded the 1 clue in r2c7 couldn't be satisfied by a bishops sum, and had to be a knights sum, which gave me 3 in r1c5).
I saw the video at over 2 hours and approached with trepidation. What a wonderful puzzle! This video was interrupted by: A fly in a web The Famous Five An owl A moth 😆
1:01:28 I think it's possible to eliminating 4 using bishop sum here. There are two options for a bishop move there to get a 3 and a 1. One option is the 4 is not grey and takes its 3 in r1c8, but that would close off grey from further growth with only three cells taken and so can't be it. The other option is the 4 IS grey it takes the 3 in r1c6. But in that case grey needs to take a 1 in r3c9 and NOT take whatever is in r1c8, and once you connect up grey it becomes clear that the other that region took r1c8 is penned in and cannot grow to size 9.
Possibly my favourite out of many amazing puzzles featured lately. This one took me about 4 hours. I worked on it for an hour after placing two 6s in the same row, so I had to redo a lot after finding the mistake. But of course having gone through most of the logic already, amde the solving easier the second time around. I really loved the ruleset with the combination of the original chess sums and renban. I also enjoyed that the solving felt so linear.
Screaming at the screen: the 9 can't be part of grey because it breaks summing to 8 for both the king and bishop move and at least one of these must be met.
2:03:03 - Once I got my head around the rules it was slow but steady progress. I did check as I was going along; there no way I’d risk doing a Simon and going all the way to the end. I did make couple of errors but OMG! What an amazing puzzle. It definitely gets easier once you’ve broken in; using the R1C3 clue early was a great help though.
Got it in 1:14:56. All the 3 clues actually had to be a 7 8 or 9, because the knight moves are disjoint with the king and bishop. If the king and bishop are disjoint then the clued cell is at least 21/3. If the king and bishop share a cell, then one of them must be a 3 cell sum which together with the knight makes the clued cell at least 15/2.
I really enjoy puzzles like this, that make my brain sweat. I can feel it resisting the effort, but force it to carry on. The diagonal clues in particular threw me a bit, and I found the ending rather painful - an extra clue might have helped smooth things over.
This puzzle was very tricky but very beautiful. Started it on my own and got stuck because of a minor mistake. Then watched far enough to make sure I hadn't made any more mistakes and continued on my way. Clock stopped at 149:48 but not sure of the actual solve time.
When Simon realized orange had to connect to the bottom right corner and needed a knight's move 3-5 pair, he could have resolved that more simply by the 5-cell renban line that couldn't have an 8 by sudoku. That means it needs a 3 on the line (the renban being either 3 to 7, or 2 to 6), and placing a 3 below the line invalidates it.
Yeah, also all bishops moves were in rows 7 or 9 and on the same set as the king moves. Which also includes at least on square connected to the grey 8 orthogonally, so the 8 can't use both and will need the knights move either way.
UA-cam seemingly deleted my original reply. No idea why. I won't attempt to repeat it all, but in summary, I think you're right. Simon overlooked it. Your comment made me realise I made the same mistake in my solve. There's a way to rule out the 4 being part of the red region, but it's not straightforward.
The UA-cam algorithm is fickle. I watch both videos every day, yet Mark's video won't show on my feed, I have to actively go onto your profile. Maybe Mark has angered the Google overlords
A thing I have found about this puzzle is that the bottom right clue is not necessary to solve the sudoku, and it only use for disambiguating the regions.
1:45:40 The deduction was one way to do it but I think the simplier way was to realize that there is no eight on the orange renban which then must contain a three and it can't have one in the seventh column.
At around 1:01:00, Simon marks a 1 into r4c89 on the basis that the 4 on the 1 clue in r2c7 has to get a 1 from somewhere, but he failed to account for the fact that that 4 could be red and get the red 1 in r3c5 by knight's move. This would be utterly forcing because such a red 4 could only see one other possibly-red cell by knight's move (r4c8), and taking both that cell and the 4 into red completely forces the red region. All of this is disproved about 10 minutes later when the red region is forced downwards by the renban/king's move interaction, but it was a missed possibility at the time Simon made that mark
You sir are a gentleman and a scholar and a bishop and a knight and a king! I'm ashamed to admit how long it took me. I convinced myself it was impossible to knight that 4, so I had to go back a few times! An inconsequential premature deduction at 1:16:30. R1C8 was gray only under the assumption that the 4 isn't. Watching the video it's incredible to see that in many places Simon uses slightly different reasoning than me.
r7c8 was the only place for a 3 for a while, and needed on the pink line as the max was at most 7. So no 3 for the bishop's move, leaving the knight's and placing the 5 to add up to 8 in r8c7, and making the last orange cell.
13:02 What you should focus on is the fact that R1C1 is a lnight, king and bishop all at the same time. And you haven't dealt with the bishop move yet. R2C2 and R3C3 are both blue. And at least one of R1C2 or R2C1 are kings move away. If this was all there was, then R2C2 would add ONE bishop cell and ONE king cell and still sum to the same total. Which is impossible. Either the king or the bishop takes 3 cells to make the sum of R1C1. The bishop can only just take 3 cells if R4C4 is in the region. But one thing is for absolutely certain, R3C3 is blue because the bishop needs to count at least 2 cells. It's pretty obvious that R1C1 is a high digit. At least 6. But what happens if it's a 9? The renban line now only has pretty high digits on it. [56789] And so the king sum would be 2 cells and NOT be one or the other of R1C2 / R2C1. What about 8? Still the king would only take one of those renban digits. 7? [34567] Yeah, the king can only just take two renban digits, 3 and 4. But now the knight will have to take one cell as [56] and one cell as [12] and what cells does the bishop take? Only one of [12] is available and one of [56] but it must take one more digit because the king only took 2 cells. And the only digits left to take are 8 and 9. Which is way more than 7 at the end of all things. So if R1C1 is a 7, only one renban digit can be a kings cell or the world breaks. Now, if it's 6... [23456] Now the king can take two renban cells and even a third cell. In the case of three cells, they could be [123] and would make the knight impossible. Or they could be [134] and make the knight [26] but now you have to use a 5 on the bishop and you can't use both 1 and 2 to make 8. So no, the king is never 3 cells. And so by deduction, the bishop is three cells and R4C4 is most definitely blue! Then you think about all the possibilities for the bishop to share ONE cell with the king and still make a valid sudoku digit sum. And i haven't done all those possibilities but i am thinking R1C1 is a pretty high digit indeed.
30:28 If R2C3 is a bishop and a 5, then it would see a 2 in R3C2 and make R1C1 a 7, which it can't be. And further more, the bishop would have to see a 3 but the 3 is on the renban and is thus never seen by the bishop anyways. R2C3 is a king summing to 6. R3C2 is a 2 and R1C1 is an 8. The bishop R2C2, R3C3 and R4C4 is a [134] and R4C3 is a 5. The king summing to 8 from R1C1 sees at the very minimum a 7 in R1C2 or R2C1. R2C2 is therefore a 1. R3C3 becomes a 3 and R4C4 becomes a 4.
at 1:50:00, a lot of the later fretting and uncertainty could have been cleared up by considering the 9 in R7C6 the right way. Specifically, asking if it could be in the same region at the clued 8 in E8C5. Because the 8 in R8C5 has a 2 clue, then two of the three chess moves MUST apply, King, Bishop, or Knight. If the 9 was in the same region, it would break the total for BOTH King AND Bishop, leaving ONLY a single rule, Knight, to apply to the clue. Thus the 9 MUST be in the purple region, which disambiguates most all of row 7, and greatly eases the complexity of the following logic.
1:55:00 (about) Simon returned from the correct path 🙂 r7c6 9 could not be gray because it hits r8c5 8 with both king's move and bishop's move at once.
at 1:54:57 when he found out 4 is grey, couldn't he instantly know that the other 4 was purple and then even with the shortest route possible purple could never get toe the 12 in the buttom right. allowing him to fill in most of the purple and grey area, and from there the chess sums would be way easier to spot. Am i missing something? i was screaming at my monitor for simon to color the other 4 purple haha
Agh and then same with the king's move deductions ignoring the 4 that's already in the region, think Simon (understandably) hit a fatigue wall on this one...
48:10 “These 7 different digits will add up to 28 at least, because that’s the triangular number for 9.” My whole life-view is ruined, because Simon has been telling me for years that the triangular number for 9 is 45!😮
In the last grey region, as 4 is grey, king sum is always greater than bishop. So king sum is nonsense, and 1-7 pair for knight is needed, and it feels to fall apart much faster than it took me to the end of the video (but i wasn't as tired as you at that point, so no yelling)
At 1:41:00, The c7/8 renban cannot have 8 on, so must have a 3 and can be placed. Now, a bishop move for r9c9 can’t work, because 17/26/35 are all unavailable. Corner clue is now a knights move, using the placed 3, and placing the 5
Why does Simon go a little insane when defining the gray area? There are so many options he doesn;t consider... not to mention he shades a cell gray for testing and doesn't undo it because he starts spamming the white colour instead of undo
Much respect for reading the famous five to your children. I grew up reading Enid Blyton, as did my mum, and possibly her parents too (born 1930, and one book I have from my childhood was first published 1943) Say what you like about her writing, I don't get why books can't be superficial. Plenty of people watch soap operas, which are as superficial as it gets.
I've actually met 2 of the original Famous Five from 1971 - Gary Russell and Marcus Harris. It was awesome. But now I'm wondering who Simon was referring to at 54:54...?
I guess, sometimes you need to say you're doing well and a smart-ass etc., because I saw that r1c2 can't be 5 due to lengthy renban on the right of r1, which would obviously have a 5 in it
1:21:01 I think there's a better way to prove this wrong: you only have one 59 cell and you need another. If you try to take two extra cells at the bottom, you need to pass through a 1234 cell and you already have all those numbers on the gray region. Of course, I don't know yet if you managed to see something else: when you try to disprove the 4 to be gray, you put two grays on r1 and after disproving that, you forget to erase one of them, and just put the 4 in the corner. i do not think it was totally prove, so if its right, I think it was lucky. (I am just at the time stamp I already write at the begining ot the comment, so I need to see the rest for the answer),
Thank you so much for the feature, and a wonderful solve! Sorry for keeping you up so late 😅This is almost certainly my hardest puzzle, and is the culmination of 3+ years of setting, solving, and of course watching CTC constantly. Ever since discovering CTC about 4 years ago, my life has permanently changed for the better. I truly can't thank you and Mark enough for the endless positivity and growth you have provided me.
[Some potential spoilers ahead]
I may make a video solution of this puzzle at some point, but for now I'll make a few brief comments:
1) The break-in becomes noticeably easier if you consider R1C3 earlier (and then its geometric/renban effects). I did indeed craft the break-in around "what happens if 3 is in the corner," and the second part of that was "what happens if two 3s are close to each other?"
2) The end becomes noticeably easier by focusing on the 9 in R7C6. If it's gray, it breaks both the king sum and the bishop sum, leaving only 1 chess sum available for R8C5.
3) Although it is easy to try and whittle possibilities down (and there is really nothing wrong with this approach), I intended for most if not all of the deductions to be made with a min/max approach. One example is when you were considering the yellow 9 seeing 7 different cells. That is indeed impossible because those 7 cells have a minimum sum of 28 yet 9*3=27. Granted, asking the right questions is not easy here, but I tried my best to always have a strategic way for every step.
This is just a little insight into my intentions. All that said, I enjoyed your solve immensely, and this puzzle is NOT easy---so many many kudos to you Simon. Thanks again for being such an important part of my life all these years. Cheers!
Mind blowing from you!! Huge respect for how you set and this is just out of this world!! Thank you for your 3 points above and insight into your brilliant mind. Would love to see a video solution of this or how you set it!! 🙂
Super puzzle from you Nordy! Absolutely loved it! Two of my favourites are turning out to be chess variant sudokus (Christian König's and yours!)
Regarding point 2: You can know straight away that king's move isn't included for this sum, simply because all the 9's available to gray are always touching the 8, and one of them has to be taken!
never once in the history of the world has it been obvious to everyone when Simon says 'I'm sorry if its obvious to everyone, but its not to me'
Yep. He's ludicrously capable at untangling the most opaque rulesets.
@@VonBladeagree with both of you! On this one I just listened to Simon while I did other stuff.
Is this about the 9 that is a kings move and bishops move away from the 8?
@@fdlatyt that is certainly what i spotted in the end. somehow simon gets too focused on a specific that he forgets the same rules apply to other things as well. i think its a sort of tunnel vision for him
Came here to say this. Both the 9 being a kings move and bishop's move away from the 8 in the bottom gray and how he's looking for a 6/2 kings move pair in the bottom gray completely forgetting there's a 4 in the king's move as well.
A 15-minute Simon puzzle: takes me 5 minutes.
A 30-minute Simon puzzle: takes me 30 minutes.
A 45-minute Simon puzzle: takes me 2 hours.
A 2-hour Simon puzzle: I cannot risk losing my home, my job and my family by devoting the years necessary to attempt this.
0:7:10 Maybe he spent all that time working how how a knight moves? (ha!)
@@Timlagor Ha, so many times he was focusing on a kings move while also having another kings move square coloured making it impossible.
I really enjoy being a backseat sudoku solver. "Sort the 1 and 3 in the blue region and it places 1 in yellow, Simon" at a puzzle I could never in a million years solve on my own lol!
haha exactly
"why don't you see XYZ Simon??" while he solves logical paths I could never come up with
i know right! and sometimes he solves them in the most complex way (ex: the purple 4 at the end was purple simply because the other 4 was grey, but he did that in such a complicated way ahaha). but tbh, noticing this stuff makes me better a sudoku in general cause i can rely on simon to be right in the end
One of my favourite things on this channel is when Simon has to pause the video and read to his girls. Man’s got his priorities sorted.
I would definitely buy a "I'm one of Simon's favorite people" t-shirt
I think the back should have small print that says "I know the secret"
Same!!!
Today is my birthday Simon! I turn 23. Nobody in my life would probably send you message about my birthday since they don't understand why I watch these, but I do greatly enjoy watching every day.
-Will
Happy birthday Will!
Happy birthday 🙂
Hope you had a happy birthday, @cybersoul3371 Will!
Thank you for the birthday wishes 😊
@@cybersoul3371 Happy birthday, glad you're a part of the community :)
it’s been insanely hot and dry here in Brazil due to some wildfires, so to be able to solve (or at least watch Simon solve 😂) some sudoku in the comfort of my room with some AC and a nice cup of water is a real privilege. thanks for making all our days better you two!
I think there was a logical error here. At 1:15:19 Simon hypothetically colours R1C8 grey in order to prove that R2C7 is purple, but then having proved that R2C7 is not purple, he forgets to un-grey R1C8. I wonder how you can actually prove that R1C8 is grey cause that's where I got stuck...!
Yeah that's true. The way I saw is to go for the logic of the green region first, which also lets you place the 3 of the red region into R6C7. Orange has to extend, which makes it go to R5C8. Afterwards you look at the chess moves of R3C7. It can't be in orange because R5C9 would be the only diagonal box in its region and kings move doesn't work. So it has to be grey which limits the option to bishop and knights move and the 2/7 pair at the top in R1C6 and R1C8 is the only way to make that happen.
1:21:59 I think the deductions around knights moves here proves it. Once R3C7 is 9 and isn't king, you need to look at the possible digits.
R1C6 is definitely grey, R4C9 is not grey or you trap the blue region. 134 have been used in grey, so the only option left is 27. If R1C6 is 2 then R1C8 is grey and 7, as R5C8 isn't 7. If R1C6 is 7 then R1C8 is 2 and R5C8 can't be 2.
Sorry, that looks like I've smashed my fist into a keyboard but I think the logic makes sense?
I think the simplest way to see it is to ask whether r1c9 can be grey. If it is, then r1c8 must also be grey, to connect the grey region together. If that’s true, then you can’t put a 4 onto the renban, so r1c9 must be a non-grey 4
@@leftysheppeyyeah i found something similar. the 9 has to take 2|7 by knight's moves (those are the smallest digits left in grey). putting a 2 in r5c8 creates a 1|3 pair in r5c67, which forces a 4 into r5c9 and that cuts off the blue region (which has to take the 4 in r1 no matter what). therefore the grey 9 is looking at r1c6 and r1c8, pushing 4 into c9.
Yah, good catch, he didn't remove the grey from the square and just kept it without logic.
10:17 You didn’t really expect me to have a go, right? Right?
lol... Yeah, I clicked on the video, and said hey, should I try it? Then I looked at the length and said "Nope".
@@johncox7169same!
1:56:43 I think a beautiful piece of logic for solving that part is thinking about digits in the immediate diagonals to cells with 2 chess sums constraints: For example, the 9 is in the upper-right diagonal to the grey 8 cell that has 2 chess sums constraints, but that position belongs both to the set of cells reached by a Bishop move AND to the set of cells reached by a King's move from the 8, which means it cannot possibly belong to the grey area (otherwise it'd be impossible to satisfy 2 chess sum constraints), therefore it's purple. The same is true for the 8 in the upper-left.
Yeah I agree, I think the idea is to think which cells are not part of the chess sums and give them a different color
1:52:10 You just proved that 9 can't be grey. It's both a king's and a bishop's move away.
The 9 being purple also makes the 7 and the 5 next to it purple, so grey has to get to the other 5.
Purple can't flow around the right side of the grey 8 as there wouldn't be any moves available, as you showed. So it has to flow around the top to reach the leftmost 4, and the grey 5 connects via the bottom row up to the 4 and goes on through to the 1, as purple can't reach it. The colour of the 3 and the 9 in row 8 are resolved by sudoku.
This is an epic popcorn-worthy video! Get settled in, and enjoy the proceedings!
As someone who doesnt like word games, I do really enjoy the crossword videos every week. As you explaining the logic behind the clues is very facinating
2 hour plus!?!?!? Time to settle in , grab popcorn , get coomfy..and watch Simon get to work on this behemoth!
I got a hamburger and fries and settled in. I still would like Simon to read to us!
@longwaytotipperary Simon reading to us would be heavenly. Mmm..hamburger...always medium rare for me 😁...will crispy well done fries
@@davidrattner9 medium well for me. I like my fries crisp on the outside and fluffy on the inside. And with ketchup! 😋
Just what I need this evening. A Cracking the cryptic movie with a glass of wine 🍷 📽 😊
started doing this sudoku w/o looking at the video length, immediately stopped w/ no idea what to start with, and immediately understood that it won't be easy with the 2hr video
What a puzzle. It took me ages ..... but nevertheless it was fantastic and a real adventure.
1:27:18 finish. Such a fun puzzle, but logic like pulling teeth. Very colorful in the end though. Excellent!
Right at the end, between grey and purple, the 9 in r7c6 breaks the knight and the king move so must be purple. At some point you ruled it out of satisfying the king move but then didnt count it in the bishop move.
Yep (started at 1:51:50), Simon _immediately_ noted that the 9 broke the king's move, while at the same time _not_ noticing that it also broke the bishop's move. It was a screen-shouting moment. :)
Really good to see Nordy featured again ...
One piece of logic late on - Simon, you looked exactly in the right place - R7C6(=9), but moved on too quickly to realise. If R7C6 is grey it breaks both the kings move and bishops move sums for R8C5. I am sure if you did two or three of these that would be an automatic deduction. You got (a version) of it eventually.
This channel is so cool! I'd never find puzzles like this otherwise, and I'd certainly never attempt them, but with a couple assists from Simon I just had a lovely Sunday evening working through this. Thanks for everything you do
Two hours of solving, zero seconds of boderom watching it 🙂
Before clicking the link and attempt the puzzle myself, let me check the runtime is indeed 20 minutes and not 2 hou- 😮
I think the much simpler way of solving the bottom of the grid is to ask where grey gets it's 9. No matter where it is, it's a kings move away, and so the two constraints must be knights and bishops moves. To avoid the grey 9 falling on the bishops diagonal, it must be r8c4. Everything else collapses from there without having to pick at digits. Purple takes up the whole top row, the 2 constraints for the grey 8 fills out the bottom row from the only places that can fulfill the bishop and knights moves and then it's just basic sudoku for the rest.
At 1:16:37, isn't that deduction based on a cell that was colored on the assumption that r2c7 is purple? Why can't r1c8 hold that number at that point?
Yes, I think it was an oversight by Simon. It happens sometimes.
I think you can get to that digit with a few extra steps by deducing that r1 c9 must not be gray (call it blue), and that blue takes one of the pair in r1c8 and r1c9 and must pass through the other half of the x-wing in r5c8 and r5c9 to get to 9 cells, forcing the value of r5c8, which in turn forces r1c9
I just paused the video at this point to see if anyone had caught this, and yours was the first comment I saw. I agree, he got a little lucky. He should have uncoloured r1c8, and that might have been the 4 in row 1.
The way I eventually resolved the placement of 4 in row 1 was to see that the five cell renban lower down c8 had to have a 4 on it, since its top digit is 1,2,3 or 4, and then the 4 has to appear in c8. So r1c8 cannot be 4.
That by itself doesn't force r1c8 to be grey, but the x-wing on 4s in rows 1 and 5 is resolved with 4 in r5c8, and the only way then to satisfy the 2 chess sum clue in r3c7 requires a 27 pair a knights move away in grey in row 1, making r1c8 grey.
(I think I also concluded the 1 clue in r2c7 couldn't be satisfied by a bishops sum, and had to be a knights sum, which gave me 3 in r1c5).
15:28 new favorite Simon quote: "we know this is a positive number that does not equal itself" 😂
This was monsterously difficult, but I pushed through in just under 3h. What a puzzle. So easy to miss a logical error. Liked it A LOT🎉
I was so annyoned at the end, when Simon didn’t find out, that 9 can’t be grey, because it breaks both king and bishop moves for grey 8 :D
It was driving me crazy when he was considering the 9 being grey at the end without realizing it would break both king's move and bishop's move 😅
I saw the video at over 2 hours and approached with trepidation. What a wonderful puzzle!
This video was interrupted by:
A fly in a web
The Famous Five
An owl
A moth
😆
This was beautiful, took me just over 2 hours
1:01:28 I think it's possible to eliminating 4 using bishop sum here. There are two options for a bishop move there to get a 3 and a 1. One option is the 4 is not grey and takes its 3 in r1c8, but that would close off grey from further growth with only three cells taken and so can't be it. The other option is the 4 IS grey it takes the 3 in r1c6. But in that case grey needs to take a 1 in r3c9 and NOT take whatever is in r1c8, and once you connect up grey it becomes clear that the other that region took r1c8 is penned in and cannot grow to size 9.
Possibly my favourite out of many amazing puzzles featured lately. This one took me about 4 hours. I worked on it for an hour after placing two 6s in the same row, so I had to redo a lot after finding the mistake. But of course having gone through most of the logic already, amde the solving easier the second time around.
I really loved the ruleset with the combination of the original chess sums and renban. I also enjoyed that the solving felt so linear.
Closing up the top of the yellow region at the very end was the most satisfying part of the solve.
71:29 for me. Omg, what a puzzle!! Really enjoyed it, absolutely fantastic!!
This was an amazing puzzle, I didn't think I was gonna be able to do it, but after more than 2 hours I managed to finish it. Thank you for the video!
A thought for the fly
Rules: 03:20
Let's Get Cracking: 10:21
Simon's time: 1h54m55s
Puzzle Solved: 2:05:16
What about this video's Top Tier Simarkisms?!
Bobbins: 5x (25:56, 34:25, 1:00:59, 1:10:22, 1:10:22)
Three In the Corner: 4x (04:47, 1:02:46, 1:04:59, 2:05:46)
And how about this video's Simarkisms?!
Ah: 19x (17:33, 22:37, 22:37, 26:05, 33:58, 38:21, 39:12, 41:35, 56:06, 1:02:31, 1:04:21, 1:06:36, 1:06:52, 1:11:55, 1:14:34, 1:14:38, 1:26:27, 1:55:40, 2:00:26)
Hang On: 18x (06:36, 07:37, 13:36, 14:15, 14:47, 22:53, 31:21, 32:34, 32:58, 35:55, 38:21, 42:08, 54:27, 1:26:34, 1:27:39, 1:54:14, 2:00:26, 2:04:09)
Sorry: 13x (36:04, 44:18, 45:23, 1:02:11, 1:09:00, 1:10:02, 1:16:26, 1:43:50, 1:52:40, 1:55:45, 1:56:37, 2:00:48, 2:03:39)
In Fact: 12x (13:18, 13:18, 14:22, 28:42, 28:42, 28:49, 40:43, 49:02, 51:02, 1:00:33, 1:08:57, 1:24:58)
By Sudoku: 7x (50:37, 1:10:15, 1:23:34, 1:25:14, 1:47:17, 1:48:37, 2:03:57)
Wow: 7x (09:30, 10:12, 30:53, 53:21, 1:44:09, 1:45:25, 1:52:26)
Pencil Mark/mark: 6x (32:14, 58:08, 59:48, 1:14:34, 1:33:15, 1:40:21)
Clever: 5x (01:07, 1:08:54, 1:51:25, 2:00:07, 2:05:23)
Beautiful: 5x (44:24, 1:22:29, 1:25:38, 1:29:36, 2:05:39)
Obviously: 5x (03:32, 55:04, 1:18:59, 1:49:35, 1:54:27)
Good Grief: 4x (10:07, 54:34, 1:17:45, 1:31:57)
Nonsense: 4x (31:21, 35:11, 1:10:02, 1:18:21)
Fascinating: 4x (27:30, 45:33, 1:01:52, 2:05:51)
What on Earth: 3x (41:12, 1:50:18, 1:54:22)
Useless: 2x (36:52, 1:02:21)
Naughty: 2x (42:03, 1:38:50)
Elegant: 2x (00:33, 00:36)
Surely: 2x (10:26, 1:10:32)
What Does This Mean?: 2x (1:08:02, 1:08:21)
Triangular Number: 2x (36:36, 48:14)
What a Puzzle: 1x (2:05:17)
Bother: 1x (44:43)
Stuck: 1x (55:19)
Horrible Feeling: 1x (1:14:44)
Lovely: 1x (02:41)
Brilliant: 1x (1:17:43)
Going Mad: 1x (46:29)
Our old Friend Sudoku: 1x (1:35:14)
Come on Simon: 1x (1:42:17)
Magnificent: 1x (2:06:04)
Doesn't get a Song: 1x (04:50)
Phone is Buzzing: 1x (54:44)
Let's Take Stock: 1x (1:35:45)
Fabulous: 1x (39:02)
That's Huge: 1x (26:23)
Nature: 1x (1:20:25)
Most popular number(>9), digit and colour this video:
Twenty Seven (7 mentions)
One (183 mentions)
Blue (75 mentions)
Antithesis Battles:
Even (8) - Odd (0)
Lower (8) - Higher (2)
Highest (3) - Lowest (2)
Row (15) - Column (15)
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!
Dude, I don't know even why this bot exists, but I just love it XD
Screaming at the screen: the 9 can't be part of grey because it breaks summing to 8 for both the king and bishop move and at least one of these must be met.
2:03:03 - Once I got my head around the rules it was slow but steady progress. I did check as I was going along; there no way I’d risk doing a Simon and going all the way to the end. I did make couple of errors but OMG! What an amazing puzzle. It definitely gets easier once you’ve broken in; using the R1C3 clue early was a great help though.
Got it in 1:14:56. All the 3 clues actually had to be a 7 8 or 9, because the knight moves are disjoint with the king and bishop. If the king and bishop are disjoint then the clued cell is at least 21/3. If the king and bishop share a cell, then one of them must be a 3 cell sum which together with the knight makes the clued cell at least 15/2.
Solved in 2:02:22. Brilliant puzzle.
I really enjoy puzzles like this, that make my brain sweat. I can feel it resisting the effort, but force it to carry on. The diagonal clues in particular threw me a bit, and I found the ending rather painful - an extra clue might have helped smooth things over.
If you watched the insane display of rule remembrance and live solving with commentary, and didn't hit like, for shame.
This puzzle was very tricky but very beautiful. Started it on my own and got stuck because of a minor mistake. Then watched far enough to make sure I hadn't made any more mistakes and continued on my way. Clock stopped at 149:48 but not sure of the actual solve time.
amazing puzzle, I like the ruleset
When Simon realized orange had to connect to the bottom right corner and needed a knight's move 3-5 pair, he could have resolved that more simply by the 5-cell renban line that couldn't have an 8 by sudoku. That means it needs a 3 on the line (the renban being either 3 to 7, or 2 to 6), and placing a 3 below the line invalidates it.
R7c6 never can be gray, the 9 kills king and bishop and both bust the 8 sum
Yeah, also all bishops moves were in rows 7 or 9 and on the same set as the king moves. Which also includes at least on square connected to the grey 8 orthogonally, so the 8 can't use both and will need the knights move either way.
I'm just watching the ending now. I think Simon's tired. Ruling out that 9 as grey is a lot easier than most of the steps he's already done.
Screaming that the 9 in R6C5 is purple because it's higher than 8 AND both a king's and knight's move away. Why doesn't he listen to me?
2 hours‽ I'll just watch you solve this one
Love these kind of puzzles, 86 min for me.
1:01:28 couldn't it have been a red one a knight's move away?
UA-cam seemingly deleted my original reply. No idea why.
I won't attempt to repeat it all, but in summary, I think you're right. Simon overlooked it. Your comment made me realise I made the same mistake in my solve. There's a way to rule out the 4 being part of the red region, but it's not straightforward.
@@RichSmith77 Thank you 🙂
I am a poor sudoku solver but not so poor chess player, I may overlook naked singles and X-wings but not knight attacks 🙂
@@wojciechpietrzak1981 🙂
Indeed he should have considered that possibility
I just love that you start the solve at the 3-clue in the corner
Omfg.. i opened it to do a quite puzzle before bed. Did not expect the Movie. Ig ill have yo come back to this tomorrow
The UA-cam algorithm is fickle. I watch both videos every day, yet Mark's video won't show on my feed, I have to actively go onto your profile. Maybe Mark has angered the Google overlords
I love this type of puzzle❤
Whew! Lovely puzzle, very tasking. 150:09 for me.
A thing I have found about this puzzle is that the bottom right clue is not necessary to solve the sudoku, and it only use for disambiguating the regions.
So instead of having a 1 clue, have a 0 clue so that it is a negative constraint that none of the chess moves can sum to that cell.
1:45:40 The deduction was one way to do it but I think the simplier way was to realize that there is no eight on the orange renban which then must contain a three and it can't have one in the seventh column.
Who woulda thought theres a more outtathisworld ruleset than the simple wheel/rose of thermos simon did
At around 1:01:00, Simon marks a 1 into r4c89 on the basis that the 4 on the 1 clue in r2c7 has to get a 1 from somewhere, but he failed to account for the fact that that 4 could be red and get the red 1 in r3c5 by knight's move. This would be utterly forcing because such a red 4 could only see one other possibly-red cell by knight's move (r4c8), and taking both that cell and the 4 into red completely forces the red region. All of this is disproved about 10 minutes later when the red region is forced downwards by the renban/king's move interaction, but it was a missed possibility at the time Simon made that mark
You sir are a gentleman and a scholar and a bishop and a knight and a king!
I'm ashamed to admit how long it took me. I convinced myself it was impossible to knight that 4, so I had to go back a few times!
An inconsequential premature deduction at 1:16:30. R1C8 was gray only under the assumption that the 4 isn't.
Watching the video it's incredible to see that in many places Simon uses slightly different reasoning than me.
was hust going to watch this quickly before bed. then saw the length of the video. damn!
r7c8 was the only place for a 3 for a while, and needed on the pink line as the max was at most 7. So no 3 for the bishop's move, leaving the knight's and placing the 5 to add up to 8 in r8c7, and making the last orange cell.
13:02 What you should focus on is the fact that R1C1 is a lnight, king and bishop all at the same time.
And you haven't dealt with the bishop move yet. R2C2 and R3C3 are both blue.
And at least one of R1C2 or R2C1 are kings move away.
If this was all there was, then R2C2 would add ONE bishop cell and ONE king cell and still sum to the same total. Which is impossible.
Either the king or the bishop takes 3 cells to make the sum of R1C1.
The bishop can only just take 3 cells if R4C4 is in the region. But one thing is for absolutely certain, R3C3 is blue because the bishop needs to count at least 2 cells.
It's pretty obvious that R1C1 is a high digit. At least 6.
But what happens if it's a 9? The renban line now only has pretty high digits on it. [56789]
And so the king sum would be 2 cells and NOT be one or the other of R1C2 / R2C1.
What about 8? Still the king would only take one of those renban digits.
7? [34567] Yeah, the king can only just take two renban digits, 3 and 4. But now the knight will have to take one cell as [56] and one cell as [12] and what cells does the bishop take?
Only one of [12] is available and one of [56] but it must take one more digit because the king only took 2 cells. And the only digits left to take are 8 and 9. Which is way more than 7 at the end of all things.
So if R1C1 is a 7, only one renban digit can be a kings cell or the world breaks.
Now, if it's 6... [23456]
Now the king can take two renban cells and even a third cell. In the case of three cells, they could be [123] and would make the knight impossible. Or they could be [134] and make the knight [26] but now you have to use a 5 on the bishop and you can't use both 1 and 2 to make 8.
So no, the king is never 3 cells. And so by deduction, the bishop is three cells and R4C4 is most definitely blue!
Then you think about all the possibilities for the bishop to share ONE cell with the king and still make a valid sudoku digit sum. And i haven't done all those possibilities but i am thinking R1C1 is a pretty high digit indeed.
for the last two regions "where does the grey 8 get its 9 from" immedatly excludes the kings move as it must be next to the 8
At the end, the 8 couldn't have been a "king's move" because at least one of the cells in that cage a king's move away had to be a 9.
30:28 If R2C3 is a bishop and a 5, then it would see a 2 in R3C2 and make R1C1 a 7, which it can't be.
And further more, the bishop would have to see a 3 but the 3 is on the renban and is thus never seen by the bishop anyways.
R2C3 is a king summing to 6. R3C2 is a 2 and R1C1 is an 8.
The bishop R2C2, R3C3 and R4C4 is a [134] and R4C3 is a 5.
The king summing to 8 from R1C1 sees at the very minimum a 7 in R1C2 or R2C1. R2C2 is therefore a 1.
R3C3 becomes a 3 and R4C4 becomes a 4.
at 1:50:00, a lot of the later fretting and uncertainty could have been cleared up by considering the 9 in R7C6 the right way. Specifically, asking if it could be in the same region at the clued 8 in E8C5.
Because the 8 in R8C5 has a 2 clue, then two of the three chess moves MUST apply, King, Bishop, or Knight. If the 9 was in the same region, it would break the total for BOTH King AND Bishop, leaving ONLY a single rule, Knight, to apply to the clue. Thus the 9 MUST be in the purple region, which disambiguates most all of row 7, and greatly eases the complexity of the following logic.
1:55:00 (about) Simon returned from the correct path 🙂 r7c6 9 could not be gray because it hits r8c5 8 with both king's move and bishop's move at once.
at 1:54:57 when he found out 4 is grey, couldn't he instantly know that the other 4 was purple and then even with the shortest route possible purple could never get toe the 12 in the buttom right. allowing him to fill in most of the purple and grey area, and from there the chess sums would be way easier to spot.
Am i missing something? i was screaming at my monitor for simon to color the other 4 purple haha
1:52:00 Can't possibly be obeying the bishop's move constraint in that particular position since it would also see the 9...
Agh and then same with the king's move deductions ignoring the 4 that's already in the region, think Simon (understandably) hit a fatigue wall on this one...
48:10 “These 7 different digits will add up to 28 at least, because that’s the triangular number for 9.” My whole life-view is ruined, because Simon has been telling me for years that the triangular number for 9 is 45!😮
54:44 Yes that time I was screaming at you in my head!
In the last grey region, as 4 is grey, king sum is always greater than bishop. So king sum is nonsense, and 1-7 pair for knight is needed, and it feels to fall apart much faster than it took me to the end of the video
(but i wasn't as tired as you at that point, so no yelling)
ok normally i try every puzzle but eh.. this one... i'll sit this one out and just watch :D
At 1:41:00, The c7/8 renban cannot have 8 on, so must have a 3 and can be placed. Now, a bishop move for r9c9 can’t work, because 17/26/35 are all unavailable. Corner clue is now a knights move, using the placed 3, and placing the 5
Why does Simon go a little insane when defining the gray area? There are so many options he doesn;t consider... not to mention he shades a cell gray for testing and doesn't undo it because he starts spamming the white colour instead of undo
Julian, Dick and Anne, George and Timmy the Dog!
I think I'm gonna sit this one out and just watch the solve.
1:53:00 The 9 in R7C6 cant be grey. If it was grey it would exclude Kings and bishops move for the 8. But one of them has to be included.
1:52:00 Simon say it's probably right, and 8 = 2+6+9 XD
Way too complicated for me but I loved watching the solve!
Much respect for reading the famous five to your children. I grew up reading Enid Blyton, as did my mum, and possibly her parents too (born 1930, and one book I have from my childhood was first published 1943)
Say what you like about her writing, I don't get why books can't be superficial. Plenty of people watch soap operas, which are as superficial as it gets.
I've actually met 2 of the original Famous Five from 1971 - Gary Russell and Marcus Harris. It was awesome.
But now I'm wondering who Simon was referring to at 54:54...?
Wasn't there a misstake when Simon got the 4 in the upper right corner? R1C8 was gray as a hypothesis.
At 1:40:00 At this stage of the solve, could the 8 in the corner be solved with a 1 and 7?
15:29 This is a positive number that is not equal to itself... hmm, makes me think
LETSGOOO ANOTHER ONEEE DAY :1
At 1:01:20, couldn’t the 4 in R2C7 be red, and take the 1 in R3C5?
2 hour video?!?!?! Do I even TRY to attempt this?? hahaha
"Sandra, cancel my 3 o'clock"
wth, the ending was so painful to watch. Simon not seeing for 20 minutes that he was constatly adding the 9 i r7c6 to the 8 total...
I guess, sometimes you need to say you're doing well and a smart-ass etc., because I saw that r1c2 can't be 5 due to lengthy renban on the right of r1, which would obviously have a 5 in it
1:26:37 : It actually was a 4, just not a red one lol
1:25:00 in.. look at 9s. Column 4,6 and 8 create a swordfish so where is 9 in row 6?
The last 10 minutes of this video was some of the most painful to watch...
1:21:01 I think there's a better way to prove this wrong: you only have one 59 cell and you need another. If you try to take two extra cells at the bottom, you need to pass through a 1234 cell and you already have all those numbers on the gray region.
Of course, I don't know yet if you managed to see something else: when you try to disprove the 4 to be gray, you put two grays on r1 and after disproving that, you forget to erase one of them, and just put the 4 in the corner. i do not think it was totally prove, so if its right, I think it was lucky. (I am just at the time stamp I already write at the begining ot the comment, so I need to see the rest for the answer),
the last 2 regions were painful to watch. geez!