I finished in 38:03 minutes. This was a truly wonderful puzzle. I really liked the tornado shape of the thermos. It looked nice, but it also felt nice to solve. The interactions on the smaller thermos was some nice geometry. I think my favorite part was the break-in with the 1's in the top thermos and all the similar logic that was used later. Once I got a 6 locked onto the diagonal in box 9, the puzzle fell very quickly. The interactions and geometry in this puzzle were so fun to do. This was some fantastic setting, Sudokun. As always, it feels good to beat Mark's time. Great Puzzle!
46:59 for me! I really liked that. Every time that I felt a little stuck and thought I needed to watch the video for help, I would immediately spot what I was missing as soon as I hit play and got through it all on my own, which was nice! 😅
The trick for me when Mark got stuck was looking at 9s on the positive diagonal, which allows you to rule 9 out of r4c1, and therefore 9 in box 4 must be in column 3, which resolves the bottom thermo.
It is rare that I can solve sudoku faster than the video length, but today I did! I was stuck about same way as Mark. Way out for me was noticing that R9C3 could not be 9. If it was 9 you could not put 9 on the negative diagonal. Removing 9 from R9C3 did give 5 to R9C5 and solved much of the bottom thermo. Nice puzzle! I like this one.
For most of the harder puzzles I solve I take so long at them that I have to step away and get on with some other part of my life. I nearly always notice something upon my return that I could have "easily" seen before. There is definitely a refreshing factor. I think this is why some ideas take shape in the morning that I could not grasp the evening before. Thanks for this video, Mark, it is always a pleasure to watch you solve an intricate puzzle. I had the hubris to think that this must be an easy one because there was so much going on in the grid, but not so! I have set my solve aside to enjoy watching your video, and maybe later this evening I'll return to it. And probably I'll see something "obvious" that had eluded me when I was deeply engaged in it this afternoon. Thank you, as always, for all of the amazing content on this channel, especially the two (or three?!) videos per day that you and Simon provide to us. I love the live solves, always so interesting and so helpful.
Honestly Mark, I don’t call if Goodliffing until I’m placing 5 candidates in one cell. 4 digits is a useful tool on German Whispers and Evens, so it shouldn’t count.
Yes. All the way back at 27:14 he had correctly pencil-marked those 9s in boxes 2 and 5. If he had trusted them back then, too, he might have seen they only left one place for 9 on the positive diagonal, in r9c1.
42:48 "I was thinking maybe this has to be 9". Well, it's the only 9 corner pencilmark remaining in the box 🙂. 9 on the positive diagonal has had only one place available since 9s were first pencil-marked in box 5 at 27:26, fifteen minutes earlier. That said, I did appallingly on this one. I ended up bifurcating heavily. The one step from Mark's solve that I missed, and would have helped me the most, was spotting r3c6 couldn't be 4 (at 14:05). I hadn't pencil marked the thermo in the row, and hadn't realised r3c5 was quite so restricted.
Yeah, this was a fairly messy solve from Mark, in that he found some extremely brilliant and difficult deductions, and yet missed many very simple things. But it's usually videos like this that show just how much better he is than me. I can't fault him too much for the simple things missed because I do that routinely also, and I know I'd make even more silly mistakes if I was on camera trying to talk through everything I do. But he always ends up finding another way through, as illustrated in this solve several times. I got completely stuck on this puzzle, but Mark did not!
39:29@#156. Not really hard, but difficult to scan. There was an awful lot going on in this grid. Thanks for the unintended(?) bonus! Edit: And it's a rare case of me beating Mark's time, too.
20:03 since 6 is on the diagonal, it means that the 6 in C2 (and therefore box 4) must be in either R5C2 or R6C2. Then, the only place for 6 in R4 is in R4C8 This little find helped me considerably at this point in the puzzle.
That was fun! The moment I identified that r2c9 couldn't be 3, the whole puzzle solved itself. (EDIT: Though I had worked a lot of the rest of the grid first -- certainly wouldn't have happened if I had done it the way Mark did!)
mark and simon: i'm always happy to see a CtC video show up in my feed. i'm especially grateful that you fellows don't edit out your mistakes; it takes a certain amount of humility and grace to let the world see your flaws. i'd enjoy a beer with you guys, which is one reason i subscribed. if i were to ever criticize you harshly, please feel free to remind me that i'm perfectly able to start my own channel and show the world my awesome (cough), flawless (cough cough) sudoku-fu. please ignore the haters, they can hug a root.
Wait . . . _(double checks puzzle)_ . . . how did I solve this in only 17:41? Guess I can't complain, but I'm usually par for the video time (if not longer).
Seeing the 5/9 pair in column 2, box 1, unravels a lot. You're starting to make things more complicated than need be. You're usually better at seeing low hanging fruit.
Both mark and Simon are good, but they both make the same error over and over, they forget the last conclusion, and forge ahead on a tangent looking for something that is indirectly changed because of there conclusion, but they never go back to look at the direct changes,in this case the 6in c2 and the subsequent 6s it revealed. That said I'm just an analyst and can only see when they miss an easy solution andstruggle to look ahead as far as they do. Keep up the good work.
I saw a post on a video a year or more ago giving a psychological explanation for the lack of scanning that we, as viewers, sometimes lament. There are two kinds of logical reasoning going on in most of these harder puzzles. There is the simple scanning, looking for pencil-marks that can be cleaned up, looking for simple eliminations. And there is the more complicated logic which follows several steps of logical reasoning, looking in multiple places in the grid, considering linked possibilities. It is actually quite hard, the psychologist said, for the human brain to switch between the surface logic and the deeper logic, and doing so is very interrupting to the deeper logical thought processes. So in a simpler puzzle neither Simon nor Mark misses simple scanning as often as they might in these more difficult puzzles, but this is entirely understandable from the 'how the brain works' kind of perspective. I would much rather they do complicated puzzles and occasionally miss something "easy" than do only easier puzzles, myself.
Sudoku be hard when you don't pay attention... EDIT: Seeing that level of indolence from Mark made my skin crawl. I don't know when or why he became so bad at sudoku... For me, it was very painful to watch.
Very loaded vocabulary here - 'indolence' carries with it a very negative connotation. Do you intend to be that strongly critical? I hope not - it is unwarranted and unkind. These are live solves, and thus we get a live person doing them. For myself, I miss obvious things all the time.
took him forever to see the 6 in box 5, and the 14 pair in box 4..and the 59 pair in column 2.... he is really slipping. back to him having a hard time seeing the left side of the puzzle, column 1 is always under pencil marked because he has an issue with is left eye, in the past he used to cover that eye doing solving.... you can clearly see that he is avoiding the left side of the puzzle.... he steps away from the camera, and they clearly told he about the 59 pair, but why not tell him about the 14 pair.
He's not doing it in front of a live audience. There's no-one to tell him. He went away, came back, and looked at the puzzle afresh. I do this all the time, and spot things I'd been missing before I took a break.
My suspicion is that the lights that he has lighting up his face are bright and he is shading his eye, not "covering it up" because he has a problem with it. I strongly doubt he would have achieved Senior World Champion in Sudoku twice in a row if he had this severe a vision problem. And remember, he is an individual person solving in front of his camera and lights - there is no one present to "tell him" anything. He is his own director, producer, technician, videographer - who will "tell him" things like you are describing?
Seem to think this was not meant to be uploaded. But happy to have a second Mark video today 😊
So recognizable to feel stuck in a puzzle, only to return with fresh eyes after a break and immediately seeing the next step!
I finished in 38:03 minutes. This was a truly wonderful puzzle. I really liked the tornado shape of the thermos. It looked nice, but it also felt nice to solve. The interactions on the smaller thermos was some nice geometry. I think my favorite part was the break-in with the 1's in the top thermos and all the similar logic that was used later. Once I got a 6 locked onto the diagonal in box 9, the puzzle fell very quickly. The interactions and geometry in this puzzle were so fun to do. This was some fantastic setting, Sudokun. As always, it feels good to beat Mark's time. Great Puzzle!
47:02 the 59 pair making a 6 in column 2 was there for 13 minutes of the video. Easily done to miss these really.
Plus the 9 on the negative diagonal that was obvious after reducing the 9 place in box 2 to column 6.
46:59 for me! I really liked that. Every time that I felt a little stuck and thought I needed to watch the video for help, I would immediately spot what I was missing as soon as I hit play and got through it all on my own, which was nice! 😅
The trick for me when Mark got stuck was looking at 9s on the positive diagonal, which allows you to rule 9 out of r4c1, and therefore 9 in box 4 must be in column 3, which resolves the bottom thermo.
Ah wow. I totally didn't see that either, good call. Diagonals are surely tricky but fun
21:43 Quincunx is the word of the week
3 videos in one day, what could be better?
It is rare that I can solve sudoku faster than the video length, but today I did! I was stuck about same way as Mark. Way out for me was noticing that R9C3 could not be 9. If it was 9 you could not put 9 on the negative diagonal. Removing 9 from R9C3 did give 5 to R9C5 and solved much of the bottom thermo. Nice puzzle! I like this one.
For most of the harder puzzles I solve I take so long at them that I have to step away and get on with some other part of my life. I nearly always notice something upon my return that I could have "easily" seen before. There is definitely a refreshing factor. I think this is why some ideas take shape in the morning that I could not grasp the evening before. Thanks for this video, Mark, it is always a pleasure to watch you solve an intricate puzzle. I had the hubris to think that this must be an easy one because there was so much going on in the grid, but not so! I have set my solve aside to enjoy watching your video, and maybe later this evening I'll return to it. And probably I'll see something "obvious" that had eluded me when I was deeply engaged in it this afternoon. Thank you, as always, for all of the amazing content on this channel, especially the two (or three?!) videos per day that you and Simon provide to us. I love the live solves, always so interesting and so helpful.
Honestly Mark, I don’t call if Goodliffing until I’m placing 5 candidates in one cell.
4 digits is a useful tool on German Whispers and Evens, so it shouldn’t count.
R6C2 is screaming at Mark.
46:07 Yes, that was indeed a good pencil mark. Since the 9 on the negative diagonal had to be in R2C2 or R4C4, it could never be in R2C4.
Yes.
All the way back at 27:14 he had correctly pencil-marked those 9s in boxes 2 and 5. If he had trusted them back then, too, he might have seen they only left one place for 9 on the positive diagonal, in r9c1.
42:48 "I was thinking maybe this has to be 9".
Well, it's the only 9 corner pencilmark remaining in the box 🙂.
9 on the positive diagonal has had only one place available since 9s were first pencil-marked in box 5 at 27:26, fifteen minutes earlier.
That said, I did appallingly on this one. I ended up bifurcating heavily. The one step from Mark's solve that I missed, and would have helped me the most, was spotting r3c6 couldn't be 4 (at 14:05). I hadn't pencil marked the thermo in the row, and hadn't realised r3c5 was quite so restricted.
Yeah, this was a fairly messy solve from Mark, in that he found some extremely brilliant and difficult deductions, and yet missed many very simple things.
But it's usually videos like this that show just how much better he is than me. I can't fault him too much for the simple things missed because I do that routinely also, and I know I'd make even more silly mistakes if I was on camera trying to talk through everything I do.
But he always ends up finding another way through, as illustrated in this solve several times. I got completely stuck on this puzzle, but Mark did not!
39:29@#156. Not really hard, but difficult to scan. There was an awful lot going on in this grid.
Thanks for the unintended(?) bonus!
Edit: And it's a rare case of me beating Mark's time, too.
14:54 for me. This was probably not meant to be uploaded yesterday, but I'm happy to get 2 videos from Mark!
20:03 since 6 is on the diagonal, it means that the 6 in C2 (and therefore box 4) must be in either R5C2 or R6C2. Then, the only place for 6 in R4 is in R4C8
This little find helped me considerably at this point in the puzzle.
"Ah, we have a 5-9 pair in column 2!" .....25 minutes later.
he saw it after stepping away, and people telling him.
@@michaelandersen-kk4fcwhich people?
@@energythief I was shouting really hard
Both Mark and Simon do this, get a pair somewhere and then not scan the row/column to see what it removes.
A 48 min video by mark usually means I cant do it but everything just seemed to click and I finished in just over 18 mins!
Hello to the people of the future who see this with heaps of old comments on it!
That was fun! The moment I identified that r2c9 couldn't be 3, the whole puzzle solved itself. (EDIT: Though I had worked a lot of the rest of the grid first -- certainly wouldn't have happened if I had done it the way Mark did!)
mark and simon: i'm always happy to see a CtC video show up in my feed. i'm especially grateful that you fellows don't edit out your mistakes; it takes a certain amount of humility and grace to let the world see your flaws. i'd enjoy a beer with you guys, which is one reason i subscribed.
if i were to ever criticize you harshly, please feel free to remind me that i'm perfectly able to start my own channel and show the world my awesome (cough), flawless (cough cough) sudoku-fu. please ignore the haters, they can hug a root.
I found that pretty tough, not sure why, I don't think I missed anything but I was just slow to see stuff.
@@Swisswavey same here.
Yup same:)
Finished in 37:14 with help from the video. Fine puzzle!
Do you have a breakdown of which countries your followers mainly are from? I'm curious!
A neat construction, using standard constraints.
I was a bit slow scanning for constraints, but done in 52:15.
Brilliant puzzle.
Yay to three puzzles!
53:54 ... I had a bit of 'chunky logic' to rule out a particular digit from r6c9 to finish, but I'll take it
Nice puzzle!
Coming to the comments to talk about the 6 in box 4.
Was this upload supposed to be unlisted?
Fun one. Finished in 27:51.
Solved in 32:33. one more minute and it would have been an angel number
WWSD? But you are Mark! So mark the squares!
Wait . . . _(double checks puzzle)_ . . . how did I solve this in only 17:41?
Guess I can't complain, but I'm usually par for the video time (if not longer).
Dear Mark, simple sudoku is your friend.
61:31 for me. Love the Diagonal Puzzles.
I'm getting pretty sloppy. I messed this one up a couple times, then came back to it, at which point I got it in 22:31 after restarting.
00:43:11
48:31 for me. i got stuck a lot.
I think the moral to this one is basic sudoku is your friend.
8:03 for me.
a little over 29 minutes for me :D
29:57 for me
lovely
53:48 for me.
@28:20, yes, yes it is blatant.
...
59 pait in column 2 looking at a 56 in r6c2.
Seeing the 5/9 pair in column 2, box 1, unravels a lot. You're starting to make things more complicated than need be. You're usually better at seeing low hanging fruit.
This took me 9 minutes to solve... What's going on!? I am not that smart lol
Both mark and Simon are good, but they both make the same error over and over, they forget the last conclusion, and forge ahead on a tangent looking for something that is indirectly changed because of there conclusion, but they never go back to look at the direct changes,in this case the 6in c2 and the subsequent 6s it revealed. That said I'm just an analyst and can only see when they miss an easy solution andstruggle to look ahead as far as they do. Keep up the good work.
I saw a post on a video a year or more ago giving a psychological explanation for the lack of scanning that we, as viewers, sometimes lament. There are two kinds of logical reasoning going on in most of these harder puzzles. There is the simple scanning, looking for pencil-marks that can be cleaned up, looking for simple eliminations. And there is the more complicated logic which follows several steps of logical reasoning, looking in multiple places in the grid, considering linked possibilities. It is actually quite hard, the psychologist said, for the human brain to switch between the surface logic and the deeper logic, and doing so is very interrupting to the deeper logical thought processes. So in a simpler puzzle neither Simon nor Mark misses simple scanning as often as they might in these more difficult puzzles, but this is entirely understandable from the 'how the brain works' kind of perspective. I would much rather they do complicated puzzles and occasionally miss something "easy" than do only easier puzzles, myself.
Sudoku be hard when you don't pay attention...
EDIT: Seeing that level of indolence from Mark made my skin crawl. I don't know when or why he became so bad at sudoku... For me, it was very painful to watch.
Very loaded vocabulary here - 'indolence' carries with it a very negative connotation. Do you intend to be that strongly critical? I hope not - it is unwarranted and unkind. These are live solves, and thus we get a live person doing them. For myself, I miss obvious things all the time.
took him forever to see the 6 in box 5, and the 14 pair in box 4..and the 59 pair in column 2.... he is really slipping. back to him having a hard time seeing the left side of the puzzle, column 1 is always under pencil marked because he has an issue with is left eye, in the past he used to cover that eye doing solving.... you can clearly see that he is avoiding the left side of the puzzle.... he steps away from the camera, and they clearly told he about the 59 pair, but why not tell him about the 14 pair.
Who is “they”? Lmao
He's not doing it in front of a live audience. There's no-one to tell him. He went away, came back, and looked at the puzzle afresh. I do this all the time, and spot things I'd been missing before I took a break.
My suspicion is that the lights that he has lighting up his face are bright and he is shading his eye, not "covering it up" because he has a problem with it. I strongly doubt he would have achieved Senior World Champion in Sudoku twice in a row if he had this severe a vision problem. And remember, he is an individual person solving in front of his camera and lights - there is no one present to "tell him" anything. He is his own director, producer, technician, videographer - who will "tell him" things like you are describing?