I've been doing sudokus for years, but this video really hammers down the importance of sticking to those pairs and not jotting down "just three candidates" like I usually do. Thank you!
Having watched nearly (probably) all of your Sudoku videos, I admired your restraint at not racing through this solve...although you sped up a bit at the end ;) Going forward, when someone over on the r/sudoku subreddit on the Reddit website asks "how do I get started on Sudoku?", I'm definitely going to point them in this video's direction. I already recommend they come over here to Cracking the Cryptic, but this particular video should be a boon to their budding solving skills. Thanks, Simon!
I'm one of those who can't follow that cursor flying and jiggling around the puzzle they way you normally do. This one was SO much better, with the slowed down presentation and the use of the color. Please do more of this? Especially redo your X wing and Y wing examples. You've previously left me completely blank. Seriously, I'm completely distracted by the fast moving zigzagging cursor (like a cat with a laser light!) that I can't even seem to understand your words. I realize this is my own issue, with a visual/aural break, and not your fault. But this was so much better!
Finally you went slow enough and explained thoroughly each move. Usually you jump too fast without explaining how you made the move. Now I'll subscribe.
Thank you so much! My brain catches this system and loved it. For the first time, after watching this video, I could resolve a hard puzzle without having to fill in with tons of numbers. I needed this video!!! Thank you so much for slow down your lesson, is the way I could grasp the tricks. ❤️❤️❤️
Your videos is very helpful. I love learning Sudoku solving from your videos! However, this video is a lot more helpful to me since you describe the steps slower than before. Please keep it at this pace. Thank you!
I'm not sure whether you've mentioned it on the channel, but it's worth noting that the trick at 4:44 where you eliminate two rows or columns at once is equivalent to finding all the places a number can go in the remaining row or column. In the video's puzzle, this means that you can equivalently place the 5 in the middle box by looking down column 5 and finding that there is only one place for the 5 to go. 8:55 shows this equivalence going the other way. You use column 5 to place the 7-9 pair, but could also come to that conclusion by looking at columns 4 and 6, noting that 7 and 9 are locked to these columns in the lower two boxes, leaving only column 5 for 7 and 9 in the top box. This doesn't drastically change anything, but it's nice to know. I generally find the 4:44 trick easier to spot than looking through rows and columns with many empty squares, so it's good to know I won't get any extra numbers from doing so. Of course naked singles are still orthogonal.
Great video. I would love to see some of the x wing and y wings at this pace. I have watched the earlier videos but they were too quick for me. Thank you for your patience. Keep up the good work. Cheers Susan
@@57thorns It's the description of the concept that's fast, at least in my experience. This video has a really slow, patient and exhaustive type of explanation, and I would love to see a similar video on X wings and Y wings, and I assume that's what Susan is asking for as well.
Thanks Simon .. this is a nice departure from the hard solves elsewhere .. I'm trying to follow your approach but often get wires crossed when switching between doubles and pencil marks .. in your "home" app you can change modes between corner marks and center marks .. it'd me great to produce a video that walks thru annotating corner and center marks and the whys/hows of when you switch .. I think in some cases they are identical .. but in other cases its crucial to distinguish between the two .. e.g. in this solve, in the lower left box you came across this exact issue and were careful to not encode a double so to not mislead yourself .. but you glossed past this fine point and I wasn't sure WHY you knew to do this .. anywa .. immense fun for this beginner .. and your labor of love is so much appreciated .. br
Simon, in all due respect to your technique, but I always go through and pick out the obvious first, the ones that are clearly the single number boxes that no other number can go into, then begin using the 'pencil marks' just exactly the same way you do it!
This was one of the most helpful videos you have put out for me. I have watched your others but for some reason this one seems to help me understand you logic much better! Thank you!!
The comments @14:20 basically changed my world (regarding Sudoku). I had been using pencil marks for any places, but limiting it to JUST the 2 possibilities is like cheating!!! Love it!
great to watch a sudoko going slower .just starting to learn and very helpful. Was doing sudulo by guessing once there were only two choices, but it was a bit like cheating and you could never advance ,learn properly the more difficult puzzles. TX
Thank you for going slow and explaining the logic. I started sudoku 3 mo ago and i struggle after i do the snyder notations to get beyond them. So... thanks.
I really appreciate the way that you teach your logical methods in doing these puzzles. Keep it up. You have certainly helped me in completing the harder puzzles I have come across. I, like others, would like to see more puzzles completed in your videos. Thanks again.
I'm so glad I found this. I've been struggling with the end of puzzles and this was a good look at how organization and diligence can really help out. I use too many pencil marks...if only there was a word for that, right???? Anyways I would love some simpler explanatory videos like this one.
If you try to solve this by putting all the candidates in all the cells right away, it looks like a huge mess, and you wind up trying to spot hidden doubles and eliminate candidates using chains. Considering a few numbers at a time as shown here is much easier.
Thanks. Good idea to slow down for the viewers. Just an observation, putting my trainer hat on, I see you go chasing the more complex rules and miss many obvious numbers that are available. You even commented on it here, but there were quite a few others. For someone following, who spots the obvious number, it's difficult to follow your other moves while the obvious one is burning. You also speeded up a lot at the end.
Exactly! I've noticed this with multiple videos on this channel. For example, I always start by looking at the number that is already given most often, which is a 6 here. From the start you can already fill in a 6 in the upper square, but only after 9 minutes he notices it.
@@Aericane I agree, I also notice Simon rarely looks at the rows or columns as a whole. At 5:29 the 5 in the bottom row is locked to the middle square (vertical 346 in it) because the the given top left 5 and the solved 5 in the top right square. The two 5:s in the bottom right square are also given by looking at the rightmost column.
Thank you for the tutorials. Please do more such videos in the the same slower pace. Additionally, would it be possible to highlight with a border a three-block region, row or column, while filling in the cells within it. It would help immensely. Its not really easy to follow the cursor. Also, I had a question as a beginner. I was under the impression we could establish the pairs only after we penciled in all the possibilities into the empty cells. Pls could you clarify.
My way of going about it has been to painfully write out all the possibilities of all cells and then start searching. This notation, where you explicitly write a possibility in a block if and only if it has a conjugate paired possibility in that same block, seems better. I was able to solve this Sudoku myself, but I took about an hour. If I went about it this way I could probably shave time off.
Simon - Does the "only when 2 squares" pencil markings approach allow you to find triples, X-wings and Swordfishes in more extreme classic Sudokus? I will try it for a while to see. My markings method for very extreme puzzles has been to do full marking but with the two-only numbers circled so I can still see them for quick eliminations and pair spotting while also using the un-circled "profligate" markings to look for the more complicated patterns.
Thanks for explaining why you're going so slow, I was yelling at the screen! I've always worked the other way round, 'ticking' all occurrences, preferring squares that will need four or fewer 'ticks'. But, I'll definitely give this a try. I'm suspicious whether only marking pairs will always give a finish, compared with marking triples, say. Anyway, not a fallen skyscraper or butterfly wing in sight, so well done!
I'm by no means an expert, or even very good, but in my experience so far, limiting to pairs really does help. Plus, you can always resort to triples after exhausting the benefits of this method on a particular puzzle.
Thank you very much for the technique. Just want to know the program you are using (using tiny figures in the square) was from any available apps or program? or developed by your self? I just feel that is very useful. Thanks again!
I'm wondering how this is classified as hard when there ara way more complicated examples and methods. Probably those that You are mentioning. But video is useful to many beginners for sure.
Your way of solving the puzzle is nice and I too solve such hard puzzles in this manner by randomly checking the numbers here and there...but I want to know the steps of solving from start to end in an orderly manner and not as a random pick of numbers..please help me with this 🙏🙏
I am greatful to your loving guidance that has made me capable of solving an impossible look sudokues and hence I can enjoy sudoku problems. I WOULD LIKE TO STATE THE PUZZLES SHOULD HAVE AN AIM OF ENTERTSINMENT AND MUST NOT TO DEPRESS THE SOLVER ....
Wow, this was considered a hard puzzle four and a half years ago? Also I'm blown away by the difference in production values between then and now. 2018 Simon is quiet and reserved and reminds me of that host of the dinosaur program who gets replaced by Mrs. Doubtfire in _Mrs. Doubtfire._ 2023 Simon is more like Robin Williams. It's crazy how there's no talk of X-wings, central pencil marks, or digits (here I think he always calls them numbers). No pencil-marking a pair down a column or the triples in boxes 7 and 9. No song for the given 3 in the corner or lament that there won't be another one to find. Not being indignant at the software for giving him hints. Compared to today, this entire video is in the uncanny valley.
when i first just had a casual go at sudoku, i involuntarily used the snyder notation...i think its only natural logic to do so...for me anyway...ie. number can go in one of two small boxes in a big box
This technique works for Easy Medium Hard & Expert level. Which I am using same method all the time. 100%. But it doesn't work on Extreme level, need to look for more complex solving techniques for Extreme level such as Unique Rectangles, XY Wing, W Wing, which I'm still struggling.
17:20 - Interesting glitch - the number turns into the "done" font when the 3 is accidentally typed, and doesn't switch back when corrected to a 4. Again at 18:51
What I especially noted was the complete restraint in pencilling in any 8s in the bottom 3 blocks ... I would have gotten trapped in eagerness to create a pair in the first column spanning the second and left-most bottom block. Thanks for being so "slow".
Thank you for going slower. Usually, I cannot follow you even if I stop the video and rewind, but this time I could.... However, I still don't understand why you didn't pencil in the 4-8 pair in the first column, compared to all of the times that you do, especially since the only missing numbers in that column were 4 and 8 at that time.
Is there ever a situation where a guess on a particular cell has to be called? I came across, in my opinion a fiendish sudoku where I logically couldn't progress any further..I'd spent almost a day on it believe it or not which I simply had to make a guess!.. It was a successful guess and I managed to finish but it was a fluke..On another day I wouldn't have be so lucky..Or can I be sure it will always fathom through logic? I love sudoku but sometimes I get a severe headache !.. Many thanks if you could give a little advise Thankyou.
Thanks a lot for this video! I have one problem though, I can't swiftly decide which block/column/number to explore next which would quickly help me solve more boxes in the grid. Like how you identified the three consecutive boxes filled and hit that column. Any more ideas on this ?
What if I pencil in 2 numbers for a pair in a 3x3 box...but when I find a pair in column it sometimes makes 3 going jn one of the directions. How do I keep it to just 2 pr? Hard to explain. Thanks.
B8 r7c4,r8c4,r9c4 has candidates 5,5,5 r7c6,r8c6,r9c6 5,5,5 so B5 MUST have candidates e r4c5,r6c5 5,5 because one cand from B8 r7, OR r8, OR r9 is certain
If you had a completed sudoku puzzle... and you erased boxes 4, 5 and 6 (the middle 27 numbers), could they then be rearranged in a different order... or does the 6 top and bottom squares (54 numbers) completely lock each of the middle numbers into a single position each?
You don't even need to erase all 27 of them, you only need to erase at most 6 cells of this puzzle after completion to make the result unsolvable. Sudoku Swami has patterns he calls "dead x-wings" or "dead swordfish", which are patterns that can't be solved without additional information. If you can find a certain digit that shares an x-wing or a swordfish with another digit, then removing both digits from all the x-wing or swordfish cells makes the puzzle unsolvable. I'll give an example. Clearly, we have to remove one of the given starting numbers to make the puzzle unsolvable, because if we have all of them given, it implies only a single solution. Let's start with the solved puzzle. We can remove the 6 from rows 4, 5, and 6, and also remove the 9 from rows 4, 5, and 6, and then the puzzle becomes unsolvable. There would be two different ways to complete it, even with these 81-6 = 75 cells given. Then to answer your question, clearly, removing all numbers from blocks 4, 5, and 6 also removes the six entries I mentioned, so the puzzle would be unsolvable.
Maybe a bit off topic question but are there any specific rules for what is considered a hard sudoku? At the online sudoku genrator I usually use, this one would probably have counted as medium difficulty.
19:47 Just out of interest: you could've placed that a whole lot earlier bc of the 2 5-pencilmarks in row 7 and 8, for they will rule each other out, no?
Took me an hour to solve this puzzle without seeing the video. I had to plan ahead and try not to confuse myself with the lot of small numbers. It's extremely hard to spot the already existing key numbers would create the ones which give me essential ramification. Gives me a headache.
PLEASE do more of these teaching/explaining videos for hard puzzles! Learning some of these techniques takes repetition for some of us. Thank you.
Thanks for this. Appreciate you going much slower and the explanation of your moves. Please do more of these.
Same ...also, you can go even slower and that would be okay (why did you choose the 5? Was there logic involved or ????)
@@heathercollins4432 lol. Of course logic was involved, I just wasn't sure how.
@@simon77047 - LOLOLOLOL
I've been doing sudokus for years, but this video really hammers down the importance of sticking to those pairs and not jotting down "just three candidates" like I usually do. Thank you!
Having watched nearly (probably) all of your Sudoku videos, I admired your restraint at not racing through this solve...although you sped up a bit at the end ;)
Going forward, when someone over on the r/sudoku subreddit on the Reddit website asks "how do I get started on Sudoku?", I'm definitely going to point them in this video's direction. I already recommend they come over here to Cracking the Cryptic, but this particular video should be a boon to their budding solving skills.
Thanks, Simon!
I'm one of those who can't follow that cursor flying and jiggling around the puzzle they way you normally do. This one was SO much better, with the slowed down presentation and the use of the color. Please do more of this?
Especially redo your X wing and Y wing examples. You've previously left me completely blank.
Seriously, I'm completely distracted by the fast moving zigzagging cursor (like a cat with a laser light!) that I can't even seem to understand your words. I realize this is my own issue, with a visual/aural break, and not your fault. But this was so much better!
I like the slower pace, better way of presenting. Thank you.
Finally. Thank you so much for slowing down. I learned a lot today. Thank you again.
what a change in your approach to solving my favourite game. Slower and steady wins the race. Thank you
I LOVE that you slowed down. I could never follow any of your videos bc I couldn't keep up. I learned sooooooo much today. Thank you.
Finally you went slow enough and explained thoroughly each move. Usually you jump too fast without explaining how you made the move. Now I'll subscribe.
You're the best 😁 I've improved my Sudoku in the past 48 hours what would of took months and cost money in the bad old 1900s. Thank you so much.
For some reason your presentation has allowed me to finally wrap my head around notations. Thank you!
This slow tutorial was the best. The others I didn't understand as well. I'd love more, and slow explanations of more difficult techniques. Thanks
Thank you so much! My brain catches this system and loved it. For the first time, after watching this video, I could resolve a hard puzzle without having to fill in with tons of numbers. I needed this video!!! Thank you so much for slow down your lesson, is the way I could grasp the tricks. ❤️❤️❤️
Thanks for taking your time over this one. I found it much clearer and easier to follow.
Your videos is very helpful. I love learning Sudoku solving from your videos! However, this video is a lot more helpful to me since you describe the steps slower than before. Please keep it at this pace. Thank you!
Would love this pace for solving some of the harder ones on the channel as well! Great stuff!
I'm not sure whether you've mentioned it on the channel, but it's worth noting that the trick at 4:44 where you eliminate two rows or columns at once is equivalent to finding all the places a number can go in the remaining row or column.
In the video's puzzle, this means that you can equivalently place the 5 in the middle box by looking down column 5 and finding that there is only one place for the 5 to go. 8:55 shows this equivalence going the other way. You use column 5 to place the 7-9 pair, but could also come to that conclusion by looking at columns 4 and 6, noting that 7 and 9 are locked to these columns in the lower two boxes, leaving only column 5 for 7 and 9 in the top box.
This doesn't drastically change anything, but it's nice to know. I generally find the 4:44 trick easier to spot than looking through rows and columns with many empty squares, so it's good to know I won't get any extra numbers from doing so. Of course naked singles are still orthogonal.
Great video. I would love to see some of the x wing and y wings at this pace. I have watched the earlier videos but they were too quick for me. Thank you for your patience. Keep up the good work.
Cheers Susan
I do not want to be snarky, but if you want to learn those techniques you could pause the video and work it out on paper (or a calc grid).
@@57thorns It's the description of the concept that's fast, at least in my experience. This video has a really slow, patient and exhaustive type of explanation, and I would love to see a similar video on X wings and Y wings, and I assume that's what Susan is asking for as well.
Took me 16 minutes for this one, learning a lot from this channel!
Thanks for slowing down , it made things more clear!
Thanks Simon .. this is a nice departure from the hard solves elsewhere .. I'm trying to follow your approach but often get wires crossed when switching between doubles and pencil marks .. in your "home" app you can change modes between corner marks and center marks .. it'd me great to produce a video that walks thru annotating corner and center marks and the whys/hows of when you switch .. I think in some cases they are identical .. but in other cases its crucial to distinguish between the two .. e.g. in this solve, in the lower left box you came across this exact issue and were careful to not encode a double so to not mislead yourself .. but you glossed past this fine point and I wasn't sure WHY you knew to do this .. anywa .. immense fun for this beginner .. and your labor of love is so much appreciated .. br
Simon, in all due respect to your technique, but I always go through and pick out the obvious first, the ones that are clearly the single number boxes that no other number can go into, then begin using the 'pencil marks' just exactly the same way you do it!
Same...
Great information about how to manage note-taking in each block of 9 squares. Thanks
This was one of the most helpful videos you have put out for me. I have watched your others but for some reason this one seems to help me understand you logic much better! Thank you!!
Thank you. For explaining the strategy w/o talking down to the viewer. I associated your technique to much like playing chess.
Thank you for this video, has actually helped me solve the harder ones I was getting stuck on earlier!
Thanks to this video, now I am 3/3 hard puzzles. Very rarely I could beat em. Ty!
This could be the most helpful Sudoku video I've ever seen. Thank you for it.
The comments @14:20 basically changed my world (regarding Sudoku).
I had been using pencil marks for any places, but limiting it to JUST the 2 possibilities is like cheating!!! Love it!
Working more slowly helps me. I haven’t been able to follow in other videos.
Loved this video. Thanks for slowing down for some of us
great to watch a sudoko going slower .just starting to learn and very helpful. Was doing sudulo by guessing once there were only two choices, but it was a bit like cheating and you could never advance ,learn properly the more difficult puzzles. TX
if it wasn't for this video, I would never be able to solve a hard sudoku without putting in every candidate and manually scanning! thankyou
Very helpful, and good speed while explaning!
Very instructive as well as enjoyable. Please do more like this!
Thank you for going slow and explaining the logic. I started sudoku 3 mo ago and i struggle after i do the snyder notations to get beyond them. So... thanks.
That was lovely, I do get myself in a muddle if I enter too many numbers so I will try the 2 only method.
I really appreciate the way that you teach your logical methods in doing these puzzles. Keep it up. You have certainly helped me in completing the harder puzzles I have come across. I, like others, would like to see more puzzles completed in your videos. Thanks again.
Your methods is very nice for salving Sudoku thanks
Genuinely helped. Thank you.
I'm so glad I found this. I've been struggling with the end of puzzles and this was a good look at how organization and diligence can really help out. I use too many pencil marks...if only there was a word for that, right???? Anyways I would love some simpler explanatory videos like this one.
Great tutorial. Thanks for going slower and explaining along the way.
That was very helpful! Thank you!
It's nice to see that sudoku software has gotten a whole lot better in the last 4 years.
yes, much better and also the video quality has dramatically increased !
Great video, I use this technique all the time, it’s the only one I know❗️✅
For newbies: if I reduce playback speed to .75, much easier to follow, and still OK to listen.
Thank you!!!!
Anyone who's been listening to cracking the cryptic long enough already had simons voice as a narrater for any little thing in their life
@@floor.smorenburg h
And for us OLD-timers, we watch at 2X
Thanks you for presenting it slowly
I found that puzzle surprisingly easy. No need for tricks. It just unfolded quite logically.
If you try to solve this by putting all the candidates in all the cells right away, it looks like a huge mess, and you wind up trying to spot hidden doubles and eliminate candidates using chains. Considering a few numbers at a time as shown here is much easier.
Thanks. Good idea to slow down for the viewers.
Just an observation, putting my trainer hat on, I see you go chasing the more complex rules and miss many obvious numbers that are available. You even commented on it here, but there were quite a few others. For someone following, who spots the obvious number, it's difficult to follow your other moves while the obvious one is burning. You also speeded up a lot at the end.
Exactly! I've noticed this with multiple videos on this channel. For example, I always start by looking at the number that is already given most often, which is a 6 here. From the start you can already fill in a 6 in the upper square, but only after 9 minutes he notices it.
@@Aericane I agree, I also notice Simon rarely looks at the rows or columns as a whole.
At 5:29 the 5 in the bottom row is locked to the middle square (vertical 346 in it) because the the given top left 5 and the solved 5 in the top right square.
The two 5:s in the bottom right square are also given by looking at the rightmost column.
Same...
Th eslower pace is much better, thanks
Thank you for the tutorials. Please do more such videos in the the same slower pace. Additionally, would it be possible to highlight with a border a three-block region, row or column, while filling in the cells within it. It would help immensely. Its not really easy to follow the cursor. Also, I had a question as a beginner. I was under the impression we could establish the pairs only after we penciled in all the possibilities into the empty cells. Pls could you clarify.
Anitha B wait a minute didn’t you comment on SudokuGuys video?
@@detroll3730 Yes, I did. Is there a problem?
@Anitha B nope just being observant
@@detroll3730 👍
That was surprisingly easy. It really IS about finding the limitations and then eliminating.
My way of going about it has been to painfully write out all the possibilities of all cells and then start searching. This notation, where you explicitly write a possibility in a block if and only if it has a conjugate paired possibility in that same block, seems better. I was able to solve this Sudoku myself, but I took about an hour. If I went about it this way I could probably shave time off.
This was extremely helpful. Thanks!
Simon - Does the "only when 2 squares" pencil markings approach allow you to find triples, X-wings and Swordfishes in more extreme classic Sudokus? I will try it for a while to see. My markings method for very extreme puzzles has been to do full marking but with the two-only numbers circled so I can still see them for quick eliminations and pair spotting while also using the un-circled "profligate" markings to look for the more complicated patterns.
I developed that same marking pattern doing them by hand, circling the obligate pairs. :)
Thanks for explaining why you're going so slow, I was yelling at the screen!
I've always worked the other way round, 'ticking' all occurrences, preferring squares that will need four or fewer 'ticks'. But, I'll definitely give this a try. I'm suspicious whether only marking pairs will always give a finish, compared with marking triples, say.
Anyway, not a fallen skyscraper or butterfly wing in sight, so well done!
I'm by no means an expert, or even very good, but in my experience so far, limiting to pairs really does help. Plus, you can always resort to triples after exhausting the benefits of this method on a particular puzzle.
Thank you very much for the technique. Just want to know the program you are using (using tiny figures in the square) was from any available apps or program? or developed by your self? I just feel that is very useful.
Thanks again!
Thanks to this video... I’m able to solve masaki hoshiko sudokus! Those are crazily hard
I'm wondering how this is classified as hard when there ara way more complicated examples and methods. Probably those that You are mentioning. But video is useful to many beginners for sure.
Your way of solving the puzzle is nice and I too solve such hard puzzles in this manner by randomly checking the numbers here and there...but I want to know the steps of solving from start to end in an orderly manner and not as a random pick of numbers..please help me with this 🙏🙏
I wanna know how they figure out which numbers to remove to set the difficulty.
good pace. Thanks.
I am greatful to your loving guidance that has made me capable of solving an impossible look sudokues and hence I can enjoy sudoku problems. I WOULD LIKE TO STATE THE PUZZLES SHOULD HAVE AN AIM OF ENTERTSINMENT AND MUST NOT TO DEPRESS THE SOLVER ....
It seems that bi-value cells and sometimes tri-value cells must be spotted in addition to double-position candidate in a box
Wow, this was considered a hard puzzle four and a half years ago? Also I'm blown away by the difference in production values between then and now. 2018 Simon is quiet and reserved and reminds me of that host of the dinosaur program who gets replaced by Mrs. Doubtfire in _Mrs. Doubtfire._ 2023 Simon is more like Robin Williams. It's crazy how there's no talk of X-wings, central pencil marks, or digits (here I think he always calls them numbers). No pencil-marking a pair down a column or the triples in boxes 7 and 9. No song for the given 3 in the corner or lament that there won't be another one to find. Not being indignant at the software for giving him hints. Compared to today, this entire video is in the uncanny valley.
Thank you.
Good Sudoku thanks
when i first just had a casual go at sudoku, i involuntarily used the snyder notation...i think its only natural logic to do so...for me anyway...ie. number can go in one of two small boxes in a big box
14:10 The square in column 1 row 9 has to be a 4-8 pair. With 7 numbers and an X-Y pair in a column, row or block, the 9th square must be an X-Y pair.
This technique works for Easy Medium Hard & Expert level. Which I am using same method all the time. 100%.
But it doesn't work on Extreme level, need to look for more complex solving techniques for Extreme level such as Unique Rectangles, XY Wing, W Wing, which I'm still struggling.
17:20 - Interesting glitch - the number turns into the "done" font when the 3 is accidentally typed, and doesn't switch back when corrected to a 4.
Again at 18:51
Thank you for going more slowly.
I like the tool you are using in solving your puzzles. Is there an app for this tool? If so, could you help me find it?
What I especially noted was the complete restraint in pencilling in any 8s in the bottom 3 blocks ... I would have gotten trapped in eagerness to create a pair in the first column spanning the second and left-most bottom block. Thanks for being so "slow".
Love ❤️ this slower video
Thank you for going slower. Usually, I cannot follow you even if I stop the video and rewind, but this time I could.... However, I still don't understand why you didn't pencil in the 4-8 pair in the first column, compared to all of the times that you do, especially since the only missing numbers in that column were 4 and 8 at that time.
An oversight, 4 and 8 were exclusive in those two cells. Good catch Mary
6:00 That's the best explanation I've heard in a while for this scenario.
Is there ever a situation where a guess on a particular cell has to be called? I came across, in my opinion a fiendish sudoku where I logically couldn't progress any further..I'd spent almost a day on it believe it or not which I simply had to make a guess!.. It was a successful guess and I managed to finish but it was a fluke..On another day I wouldn't have be so lucky..Or can I be sure it will always fathom through logic? I love sudoku but sometimes I get a severe headache !.. Many thanks if you could give a little advise
Thankyou.
Thank you sooo much ..Great help .
Seems maybe there was a bug on the web site, because it changed the fonts on the 8 before the final 8 was placed... Interesting!
Super video❗️👍✅
Really helpful thank you
Is this really qualified as a "hard sudoku" ? If so I guess there is hope for me yet :)
As always, thank you!
Thanks a lot for this video! I have one problem though, I can't swiftly decide which block/column/number to explore next which would quickly help me solve more boxes in the grid. Like how you identified the three consecutive boxes filled and hit that column. Any more ideas on this ?
his voice reminds me of Nigel Tuffnel from Spinal Tap
Thank you!
Have you ever solved any of the Maya Cosmic Number Puzzles?
Doubt -- 13:15 why did we assume 2 cannot be in column 1 row 6... You just put 2 in column 1 row 5... But I don't understand why row 6 cannot have 2?
Just move your keyboard a centimeter to the right.
Glad to see that I'm not the only one who accidently types big numbers when meaning to type pencil marks, or vice versa. 🤣🤣🤣🤣
What if I pencil in 2 numbers for a pair in a 3x3 box...but when I find a pair in column it sometimes makes 3 going jn one of the directions. How do I keep it to just 2 pr? Hard to explain. Thanks.
@3:30: Why can´t the 5 go beneath the 7 in block 6? I don´t get it. :/
It´s nice that you say "now I know..." but an explanation would be great, why?
B8 r7c4,r8c4,r9c4 has candidates 5,5,5
r7c6,r8c6,r9c6 5,5,5
so B5 MUST have candidates e r4c5,r6c5 5,5 because one cand from B8 r7, OR r8, OR r9 is certain
Is there a tool I can use for newspaper soudoku because ink soon gets messy ie the same tool you use but I can populate it from the newspaper
If you had a completed sudoku puzzle... and you erased boxes 4, 5 and 6 (the middle 27 numbers), could they then be rearranged in a different order... or does the 6 top and bottom squares (54 numbers) completely lock each of the middle numbers into a single position each?
You don't even need to erase all 27 of them, you only need to erase at most 6 cells of this puzzle after completion to make the result unsolvable. Sudoku Swami has patterns he calls "dead x-wings" or "dead swordfish", which are patterns that can't be solved without additional information. If you can find a certain digit that shares an x-wing or a swordfish with another digit, then removing both digits from all the x-wing or swordfish cells makes the puzzle unsolvable.
I'll give an example. Clearly, we have to remove one of the given starting numbers to make the puzzle unsolvable, because if we have all of them given, it implies only a single solution. Let's start with the solved puzzle. We can remove the 6 from rows 4, 5, and 6, and also remove the 9 from rows 4, 5, and 6, and then the puzzle becomes unsolvable. There would be two different ways to complete it, even with these 81-6 = 75 cells given. Then to answer your question, clearly, removing all numbers from blocks 4, 5, and 6 also removes the six entries I mentioned, so the puzzle would be unsolvable.
@@wiggles7976 Appreciate the explanation. Makes sense. Well said.
Maybe a bit off topic question but are there any specific rules for what is considered a hard sudoku? At the online sudoku genrator I usually use, this one would probably have counted as medium difficulty.
19:47
Just out of interest: you could've placed that a whole lot earlier bc of the 2 5-pencilmarks in row 7 and 8, for they will rule each other out, no?
Took me an hour to solve this puzzle without seeing the video. I had to plan ahead and try not to confuse myself with the lot of small numbers. It's extremely hard to spot the already existing key numbers would create the ones which give me essential ramification. Gives me a headache.
7.46 I am screaming about the 5s in box 7... in column 3
19:01 without any help, finally a clean solve.