By turning the rules themselves into a variable, this puzzle offers a sophisticated masterclass in meta-logical deduction. It elegantly challenges the solver to identify the lie before they can uncover the truth.
Deep Dive
Prerequisite Knowledge
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Where to go next
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Deep Dive
My Sudoku Is Telling Me Lies!!!Added:
Hello and welcome to Monday's edition of Cracking the Cryptic. And it's a it's a special day in the world of Sudoku today because it is Viking Prime's birthday.
Um and Viking Prime well many happy returns firstly. Um, Mark is scheduled to do one of your puzzles uh later on today. I hope I'm not um I Well, I hope he'll be able to do it because Viking Prime's puzzles are very difficult. Um, and uh I'm also scheduled to do something that has been made for you for your birthday, a birthday present by none other than the great Marty Sears.
Um, called H High Jinks. uh which I think is about it's got lying in it which is it's always a little bit risky um because lying puzzles can be incredibly difficult but um yes this puzzle definitely has what what are they described as shenanigans um a mischief digit a mischief digit that that causes things to not be what they first appear to be to to be to be this is what we're going to have a go into in today's video. I think it's got four stars out of five for difficulty.
So, probably not a walk in the park. Um, but probably, assuming I can solve this one, not the last Marty Sears puzzle we'll do on the channel this week because hopefully, fingers crossed, there'll be a new rat run puzzle on Wednesday. U, but this is what we're going to do today to celebrate Viking Prime's birthday. Um, now, what else can I tell you about? or if if you'll permit me, I'm just going to share with you a little tiny bit of history from the channel because on Facebook this popped up, which is um if I click that, will that work? I'm not sure it will.
That's six years ago. Six years ago today, um that happened. Cracking the Cryptic popped up from 99,900 to 100,000 subscribers.
Um, and since then we've obviously increased the subscriber base even further. Uh, I think we're sitting just below 700,000 subscribers um today. So, I mean, incredible. Thank you all so much um for supporting us. It isn't it? And it's just amazing. It's just amazing that this wonderful hobby has become as big as it has. Um and yeah, if you if you do watch and you're not subscribed, please help us to reach 700,000 subscribers. We'd be so grateful. um and uh try and teach the YouTube algorithm that these puzzles that I think they I think I still think there are literally millions and millions of people out there who if they knew about the existence of these things would just fall in love with them too.
Um and the only way we can we can we can reach those people is with your help and trying to uh encourage the puzzle that we've never quite managed to solve with the YouTube algorithm. We don't understand why some videos are popular and why others um sort of less popular.
It is a total mystery. Um but anything you can do and I think subscribing does does encourage the algorithm. Um we'd be so grateful. Anyway, that's that's that's a little bit of history. 6 years ago today, we passed 100,000. And I I must have got my silver plaque then.
Oh, yeah. No, I did. Hang on. Let me just let me just grab it. It's in my office.
>> Don't know. Can you see it?
Can you I don't know if that that'll come out, but that is the silver plaque we got um when we reached 100,000 subscribers. Now, if if you don't know, you don't get another plaque on YouTube until you get a million subscribers. You have to increase 10 times from >> um hang on let me just carefully balance that one.
>> Um you you don't you don't get another plaque. I think you get a gold plaque if you get to um if you get to a million. I don't I don't know what you get after that.
Those are levels to which I I could I can't even dream. But the um anyway, yeah, that that's that must have been when when we got we got we got the silver plaque. Anyway, I'm digressing.
What else do I want to mention? There are a few things. We're streaming tonight. Blueprints 1000 p.m. UK time.
Love to have your company 41st time.
We'll be back in the Blueprints mansion.
I'm really looking forward to it. I think Mark sort of is too. Um and yeah, fingers crossed we'll find we'll find some new secrets out then. Um also, it's the 20th today now. That means it is the closing date for our monthly competition. Uh Sandra and Nala's very popular um bug friends Sudoku hunt. It's been over on patron since the first of the month. You can see that the numbers of people who've been solving these puzzles is extraordinary. Um so we're closing in on 1,300 solvers of of the first eight puzzles. And those are the puzzles you'll need to do in order to be eligible to win the prize.
um and well over 2,000 solves of the first puzzle. So, a couple of things to mention in in this regard. Firstly, you can see there's a bonus puzzle listed there which has had 706 solves. The cracked Easter egg. I can tell you that there are no less than nine bonus puzzles. I just want to check that. Nine bonus puzzles in that pack. Eight of which are hidden. I'm not going to say anymore, but if you if you haven't spotted some of the bonus puzzles, you might want to go and look at your packs again, and you might find some more treats in there, courtesy of Sandra and Nala. So, that is a little uh well, quite a few Easter eggs hidden within it. So, so go and check those out and have some fun with those.
Um, and the other thing to mention is that the prize obviously if you if you do uh if you do manage to solve all eight puzzles, um, you'll be in with a chance of coming on to or being invited to come onto the channel to solve a puzzle. And Merrill very kindly agreed to do that. Merryill won last month's competition and that video went live this morning at 10:00 a.m. UK time. So, do check that video out. It's it's um it's something I really love doing and it it was just it was a it was a treat for me uh to meet Merrill and you'll see if you watch the video how clever she is. I mean is it phenomenal? Some of the people who who watch this channel are so clever. I cannot tell you. Um so anyway that that's that's a bonus that's on the channel this morning. Now what else? Oh, two more birthdays to do. Let me look at my list now. The first one, I have hunted high and low for how I know this, but guy, and it could even be Gee if it's the French pronunciation. Um, Guy is turning 18 today, and I wanted to say happy birthday. Um, and I can't find out how I know this. I think it might be a comment under a YouTube video, but the way YouTube makes it incredibly difficult to um filter your comments and find, you know, who said what when. And I can't find it that way. I've checked on Instagram. I couldn't find it there.
I can't find it in our emails, which is the most unreliable way of reaching us if you want a birthday shout out. But guy, I just wanted to say many happy returns on your 18th birthday. I don't know how I know it's your 18th birthday, but I think it is. And I hope you have a brilliant day with, of course, a large, well, a very heavily iced chocolate cake.
And then the other birthday is for Milo.
Milo, you've turned 21 today. So, we've got an 18th birthday and a 21st birthday. And I know it's your birthday, Milo, because your girlfriend, Erin, wrote to me and told me that the two of you watched the videos together and she thought you might like a shout out. So, I hope it's true, Milo. Many happy returns. I hope you get also some heavily iced chocolate cake. And that's all the news. Shall we have a go? Hi, Jinx by Marty Sears. I'm looking forward to this. Um, what are the rules today?
Let me just check that I have. Yeah, I think the video looks like it's recording, which is uh since I've been using OBS is always slightly concerning, but what have we got to do? We've got normal Sudoku rules applying. So, we're going to have to put digits one to nine once each and every row, every column, and every 3x3 box.
Along each line, the hexagon is referred to as position one. Okay, the next cell along is position two and so on. So this would be position three, four, five, six, 7.
Digits never repeat along a line. Okay?
So whatever we put on this line, we couldn't then repeat it. And the same will be true for other lines. Purple lines are thermos.
Um, digits along thermos always increase as you move away from the hexagon. Eg. 2 4 579 would be a valid thermo. 2 4.
Yeah, that one works. 2 4 5 7 9. So two, you can see just as mercury would rise as the temperature rises in real life thermos along sudoku thermos digits rise. So that's how thermos work.
Turquoise lines are index lines. On an index line, the digit in the nth position indicates the position along the line where the digit n appears.
I always get these things. These are so confusing to me. Eg. 3 2 1 54 would be a valid index line. 3. No, that's not long enough. Uh 3 2 1 Oh, bobbins. I don't think there is one that's of length five. Should we should we draw one? Oh, I know what I could do. It won't it won't quite let me. I'll just extend that one. Um, and then we could say 3 2 1 54 would be a valid index line.
The three in the first position indicates that there is a one in the third position and so on.
Yeah, I I remember how these work now.
So So the way these work is the the the digit in the first position is always telling you where on the line the digit one appears. The digit in the second position is telling you where the digit two appears. So here the digit two is in the second position. So it sort of indexes itself. And these pair off, don't they? So this three is telling us to write a one into position three. But then by the time you get to the one, the one is in the third position. So it's telling you where on the line to write the position, the digit three, which is back here again. So they sort of pair off and index each other. And then the five is in position four. So it's telling you where the four goes on the line, and that would go here. Um, so that's how turquoise index lines work.
Light brown lines are hit lines.
Digits can be in any order on a hit line, but the digit in the hexagon indicates how many digits along the hit line match their position number. Okay, these are the ones I find even more confusing than index lines. Um, eg. Have we got a fivelength hit? I don't believe it. I haven't got a five length hit line either. Okay, but we'll we'll extend that one.
One, two, three. Right. So this one's now long enough and we could put on this one. The example says 2 7 3 1 5.
So the two on the hexagon indicates that exactly two digits match their position number. In this case, three in position three and the five in the fifth position.
Yes. Okay. So in this one, the hexagon gives you the count of how many correctly positioned digits there are on the line with this being first position, second position, third position, fourth position, fifth position. So the three and the five are correct. So and they are the only correct ones. So you write two into this one. Um absolutely straightforward. Not. No, it's sort of straightforward, but when you're when you're if you only see them, you know, once a month, you'll forgive me if I can't remember what how they work. Um, now shenanigans.
One of the digits 1 to nine to be determined is the mischief digit. Every line follows one and only one in capital letters of the three line rules above.
But any line containing the mischief digit has been painted the wrong color. Any line not containing the mischief digit is the correct color.
Right?
So say the mischief digit was a five.
Okay. So any box or no any any line.
So every line follows only one rule.
And if a line doesn't have a five on it, it's correctly colored. And if a line does have a five on it, it's not correctly colored. Okay, I understand that. I mean, I understand the principle. I don't It doesn't mean I'll be able to solve the puzzle, but I understand what it means. Um, and they are. Let me just check. That's all the scrolling I can do. Do have a go. The way to play is to click the link under the video as usual. But now I get to play. Let's get cracking. Um, so how do we do this? So purple lines are thermos.
We can't repeat digits on lines.
And these ones are index lines.
Okay, my let me just say something up front. I think index lines are more constrained than hit lines. We're forgetting about all the lying that's going on. Now the reason I think that is that because an index line must index to somewhere on its line. It only contains the digits up to its length. So imagine this was a true index line. So again, forget about lying. then we would know that these were the digits 1 2 3 and four because whatever you you couldn't put a seven in here because that would be saying write two into the seventh position on the line which doesn't exist. So now that doesn't it's not the same for these uh hit lines because a hit line can just have any digit on it and it only contributes to the hit count if it is itself correct. So this I mean this could be silly. It could be 987 here.
none of which are remotely in the correct position and then that could be a one and that would be in the correct position and therefore the line works.
So the the flexibility of digits on a hit line I think is much more extreme than on a on an index line. But of course then you get the overlay that things are going to be wrong in this puzzle or may be wrong.
So, how long is this? 1 2 3 4 5 6 7 8 9.
So, that is a length nine line. So, that is I was going to say it it can't have a repeated digit on it.
So, it does have the mystery digit on it.
So, it's not a the So, it's not a thermo. Is that what that means? Because it would be a thermo if it was correct. it.
Yeah, if it was a thermo, it would be 1 2 3 4 5 6 7 8 9 starting in the bulb or the hexagon.
But then obviously what say the five is the mystery digit. It's got the five on it, which would say it's not a thermo anymore.
So this is either it's either an index line or a hit line.
How on earth do you tell which of those it is?
And this line overlaps with this one.
So those two digits are shared between a brown line and a fictitious line.
And you don't even know where the fictitious digit is, do you? Not the fictitious, the smelly digit, whatever it was called. I mean, there was a technical term for it, but I'm going to call it the smelly digit. The smelly digit is Yeah, it can't be twice on there because you can't repeat a digit. These that is effectively an extra region of the puzzle. It's got to contain one of the digits one to nine once each because you can't repeat a digit on the line. So maybe it's geometry.
No, actually it's not. I I was suddenly thinking, okay, where does that digit go in box one, for example, because it can't repeat on its own line, but um I it could be here or could be in those three. Hello. Uh I am back. I I have made the most almighty ricket today. Uh I forgot my sister was coming round. My sister came round. Um so I had to leave and I have been away from the computer for a very long time. So, I'm so I've got I mean, I've not done anything as you can see from the grid. Um, so it's hardly like the solve is interrupted, but for me, it does feel like it's been interrupted. Um, because I can't remember what I was doing.
Let me just quickly recapitulate. I I I ought to do this before I sit down, but um I'm conscious time's getting away from me now, so I really need to get a move on with trying to solve this puzzle. I am such a doofus. I really am.
Um, right. So, the purples. Oh, yeah. And we've got the we've got Yeah, the smelly digits. That's what we're trying to find. Digits that turn things the wrong the wrong type of line.
Um, now, okay. And I was I remember thinking this one had to be wrong because it had to have the smelly digit on it because you can't repeat a smelly digit on a line and that is a nine cell line. So So what do we do now?
We must look at thing is I just don't know. Let's have a look at this one. Um, this one is meant to be a hit line, which means that this is meant to count how many correctly placed digits there are along the line.
Now, is that true? That is a length seven line. So, this doesn't have to have the smelly digit on it, but it's quite likely to have it on it. It's got a a relatively good chance, doesn't it?
Um, it's only it's only missing two digits.
So, if it if it does have a smelly thing, it's a smelly digit. It doesn't even have to be in this box. It could be over here. And then if it was, no matter what would it do? Convert it into either the index line, a turquoise line, or or it could be a thermo.
H. Okay, let's try this box then. So, what's going on in that box? That box has got it may I mean there's definitely a smellification going on in box seven because I've got to put the smelly digit into box seven and it's going to be on a line and it's either going to convert a thermo into an index or a hit line or an index into a thermo. If it converted that into a thermo, then one in the box would have to be in one of the bulbs. A nine in the box would have to be in one of the tips. But if it converted it into a hit line, I don't even know what that means. What does the What does the hexagon have to contain if it's a hit line? It's got to contain no higher than a four. It can't even contain a four actually because if that was a four, it would be saying four digits are correctly positioned and that digit wouldn't be and that digit couldn't be. So it what can that be if it's a hit line?
It it could be a it could be a one and then these digits can be anything.
It can be a two.
It's weird actually if that's a hit line and that's a two.
Then this can't be correctly positioned on the line either because that is position two and the two would be here.
So those were two would definitely be wrong. So that would have to be three and that would have So So you can you can fill it in but it would have to go very specifically like that. Now, if this is a three, no, three won't work because that would be wrong and that's wrong. So, if this is a hit line, if it's a hit line, that's a one or a two. But if it if it's a real index line, then it's 1 2 3 or four. And if it's a thermo, it could be as high as six presumably. 6 7 8 9.
Okay.
Yeah, but short short hit lines are difficult actually. That's what that's just taught me. That probably has to be. In fact, that can't be two, can it? because I needed the fourth position when I made that a two.
I needed to put a four here. So, can that be a two? Can be a one because it would count itself. If it's a two, no, it can't be. So, that if that's if that's real, then that is a one. But if it's not real.
Ah.
Ah. Okay. Hang on. Hang on. Hang on.
Oh, bobbins. I thought I got something really good there, but I don't quite have something really good. Right. Here was the way my my brain worked. And then you can you can all laugh. I was going to say if this was not real, so if it's got a smelly on it, then I was going to say that couldn't be right because these would have to be real.
And therefore, they would both be index lines. And what do we know we put on index lines? Only only digits that are up to and including the length of the line. So this these would have both been 1 2 3 4s and that can't work. You I mean we can't put we can't put all of the digits 5 6 7 8 and 9 into column one. However, what I then didn't realize is that that's it's actually possible for well one of these lines even if this has got a smelly on it. You could put a smelly in one of those and that would that would smellify the whole line.
And therefore it wouldn't have to have 1 2 3 four on it. So if that has So how does this work? So if that's got a smelly on it then one of those has to be a smelly. If this doesn't have a smelly on it, then then one of these that well there will be a smelly in one of those six which will de which will which will smellify one of them but the other could still be also smellied. So imagine that was a smelly and that was a smelly. You could still totally smellify all of the index all of the index lines in column one.
That's vicious. Vicious and nasty.
So, so what have I actually learned from thinking about this line? Have I learned anything? And I've got that line as well. That's also a short one of those.
So, com.
So, if Yeah. Okay. They can't both be right. They can't both be uh true. I don't think if the if these lines were both true index lines, a length three index line. You see, this is this is obvious to everybody. If you if you're good at index line, not index lines, hit lines. You just know that a length three hit line could only have a one in the bulb or something and then then you're just away, aren't you? If you don't know these things, I'm going to check this one in a minute. If that's a truth, does that have to be a Yeah, that has to be a one.
So, either this is a one or that's got a smelly on it.
Yeah. But but what I was thinking is how could both of these be true? If they're both true, they both have a one in their hexagon and they can't both have a one in their hexagon.
So there's at least one smellification in those six cells. Now that's quite interesting actually for the index lines because because we know that there is a smelly in one of those. That's a horrendous pencil mark. But if you see what I mean, there can't be two smellies on those because that would put three smellies and there, you know, say the digit five is a smelly, that would put three fives in the first two columns of the grid.
So, so, so, so at least, well, hang on. I know I do know, don't I, that there must be at least one smelly on those. If, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if, if if if, if if, if, if, if, if, if, if, if, if, if, if if if there was no smellies on these, these digits would all be from 1 2 3 4."
That's definitely wrong. So, there is a smelly on one of these two lines. There is a smelly on one of those two lines and they are the they are all the smellies for columns one and two. So the smellies are in I can't really even pen but the the smellies are in those cells.
And the thing is I can't then say oh well this line's definitely not not got a smelly on it cuz the smelly could be over here. You don't you don't know.
But but we do know well I do know one of those is unsmellied which is going to be a one then there must be a one in one of those two squares. That's my first pencil mark that I can actually leave in the grid.
Now the other thing we know is that either that line or that line doesn't have a smelly on it and so it does contain 1 2 3 and four.
So So that's Well, that one's interesting, isn't it?
If that if that was real, if that was real. So, if that has no smelly on it, that has a smelly on it.
That feels like it can't work. Isn't that going to be too big? What I'm saying is this. If this if this has a smelly on it and we know one of those cells is also smellied then this would have to be that I don't know what the order would be but it would be the digits 1 2 3 4 now that means that the smelly digit which is here and I suppose in one of those the smelly digit is in one of those three cells. So, it is a 5 6 7 8 or 9.
But the bigger problem is that this can't be a thermo now cuz it's got a smelly on it.
Which means that the bulb digit is supposed to be counting.
Ah, well, it's definitely not indexing.
It's definitely not an index line because that digit is meant to say throw the one cuz this is position one. It's meant to say throw a one onto the line and one is over here. So, this right? So if this is if this is smellied, it can't be it can't be a hit line. I mean, imagine that was a five and this was a hit line. You'd be saying there are five correctly placed digits on there. But that that's that would mean this would have to be 1 2 3 4 five. Can we can barely have any of those digits on it? We couldn't have any more than the five.
No. Right. So this is not th this is not true. That has got to have a smelly on it. Um I I just don't think that that can have be correct.
So this is correct. And that is 1 2 3 4.
And that's a better pencil marker. And now one cuz I know one of these is a one and one is definitely on that line. one in column three is that's interesting.
Can I fill it in? Yes, I can. I can fill it in here. I've got a digit because now I know that this has got a smelly on it.
So, I know this is telling the truth.
It's a real thermo. And if it's a real boy, where can you put the one on it?
You can't put it halfway up because we can't put half or something in in the bulb. That is a real digit. That's a one.
And these digits are all big.
Oh. So what is this line now? Then do we know its nature?
It's either we know it's not an index line anymore. So, it's either a thermometer might be able to be that or it's a hit line but without a one in its hexagon.
So, it would have to be it would have to be the two. It would have to be this thing that we did before which it can't be actually. Yeah. Okay. How could this be a hit line? If it's a hit line, what are we putting in in the hexagon? Can't put one. So, we'd have to put at least a two. But the two makes this position impossible to fill. So this would have to be a 34. And that would get us to a count of two. But now look at the column. I've got five places which are selected from four different digits.
That won't work. So this is a thermometer.
I'm just going to write um I'm going to write t into the corner of that one.
That is a that is a thermometer.
That means right and this is a thermometer. So where is nine in this box? And the answer is I don't really know but it's got to be in a thermometer tip. It's got to be in one of those two cells which means right. So it means that this we already knew this wasn't a thermometer because it's got all nine digits on it. So it's got the smelly on it. So it which is going to change its color to something else.
But it can't. If the nine is there, it would wait a minute. Hang on. Hang on. Hang on. Hang on. Hang on.
That Well, yeah. Oh, this is beautiful. Right.
Um, I think this one might be I want to say an a hit line.
We know it's not a thermo. So, the next question is, can it be an index line?
Now, if it's an index line, this cell is saying write the one into whatever position we write into this cell. But this is 5 6 Oh, whoopsy whoopsy whoopsy whoopsy whoopsy. This cell is 5 6 7 8 or 9, isn't it? So that's saying write one into one of the last five cells on the line. Well, this can't be a one and none of those can be a one. So that's just wrong.
So, this is a hit line and it's still I mean it still feels ridiculous because well, it can't be a nine. It just can't be because nine would be saying every single digit on there is correctly positioned and the nine itself would not be correctly positioned.
So, nine is actually in one of those two and this is five, six, seven or eight.
Any of which I would have thought were monstrously hard to achieve.
I bet I bet this has to be a five. I mean, how? Okay, these digits, forgive the pencil mark here, but they're 5 6 7 8 or nine. We know these are not nine. Now, yeah, actually, so they they are 1 2 3 and four, aren't they? Because this line contains everything.
So, those digits are the same as these digits.
And that one can't be a one.
Nine. Ah, hang on. Nine is on that line.
Well, how could the nine ever be there in the hexagon?
What sort of line would that be? It couldn't be a thermo. It couldn't be an index line. It couldn't be a hit line.
Nine is definitely not there.
I know one of Hang on. This is tricky, isn't it? It's not easy to do this. One of these is the smelly.
Yeah, that is right, isn't it? Because I I know there's a smelly on there.
And I know if there was also a smelly on here, I couldn't put a smelly on these two index lines. And I know it I know there's one smelly on those.
It looks like it's going to have to be there. I'm not sure it has to be, but maybe one of those can be a smelly.
I don't know.
Oh yeah, but I know what I wanted to think about. How do I make this a hit line?
What what what's I mean in terms of what could count? What what could be correctly positioned? This can't be a one. That can be a two. That could be two. Ah, hang on. One of these digits is a one because I've got to put one on the line. So, it's not possible to write 2, three, four on that and score three hit points. I could score two hit points there.
So, two there.
That's position five. So, this is wrong.
This is wrong. The one over here is wrong. So, that's three definitely wrong digit. Uh, but these could all be correct, could they?
Well, okay, but three are definitely wrong. That's wrong. That's wrong. And the one over here is wrong. So, that can't be higher than six. That's a maximum of five. Maximum of six, minimum of five.
And I don't know what that means. Um, oh, this feels this feels it's quite interesting because Marty has presumably made this to say, "Happy birthday, Viking Prime. I'm making a puzzle in your in your style." And although because Marty's puzzles normally I think Marty holds back from displaying his pure intellect because if he actually just said here you go here's my full intellect. Everyone would just go I can't do it. Um and I think cuz Viking Prime is super clever as well. I think that what Marty's done here is gone no I'm going to show you more of my props here.
I don't really do I know whether that's real, isn't it? So that's a thermo. So I should I'm going to label that one with a T so I can actually remember that. No, no, I want a corner T, please.
So this whole box is full of thermos.
Um, if if this is a one, what what exactly am I saying? I'm saying this is a true a true hit line. And then that would be a false hit line.
So if that had if that's got the smelly on it, that would be the smelly and that would be a thermo. So this and the smelly digit I know is at least a five.
It looks maybe the smelly digit is a nine.
Um and the the rule they've got to There can only be one thing, can't they?
So, if this was if that's a one, I can't make that a thermo as well. So, yeah, if that's a one, that's a real a real hit line. So, these would have to be in the opposite order.
And if that is not a one, this is a false a false. It's not. It's just not a hit line. Maverick's flying over. It would be either a thermo, which looks quite promising, or an index line, but this would be a one. So, this would be Oh, no, that couldn't be an index line, actually.
It's got two these two digits are too high. You can only put the digits 1 2 and three on it. So, okay. So, this is not an index line ever. It's either in fact that's not an index line ever. So, that's either a thermo or a hit line.
And this is either a thermo or a hit line.
Um, okay.
Don't know what that means.
This is a real thermo, but it it mustn't be anything else.
So, Yeah. So if what happens if this cell is not a two?
Let's just make it three just for the sake of example. How many digits are correctly hit on that line?
The one is correct and every other digit can't be correct because the three is not correct. This will be therefore at least a four in the third position and everything's too high basically. But that would mean that this was a correct hit line and it was a correct thermo. So that doesn't work. I think that has to be a two. And that that will correct it because now the one is not correctly counting the number of correct hits on the line because now there are at least two correct hits on the line. And now that can't be a two.
And that does absolutely nothing.
So, one and two are over there.
Um, uh, okay, that does one thing.
One and two are over here. So, this can't be a real index line. In fact, it hasn't been able to be a real index line forever because what would it contain?
It would be the digits 1 2 and three.
and then I'd have too many repeated digits in this column. So this line contains a smelly and therefore so it's either a hit line which would which we know would make this a one. Oh, it can't be. Ah, this is a thermo. Yeah, hang on. because I know one is in one of those three positions.
And I have learned a great length that a three cell hit line has a one. If it's a real hitline, it has a one in its hexagon. So if this is a hitline, it has a one there, which it doesn't. So, this is a thermo and that means well I don't think it means very much but I feel like it means that digits at least a five because um because how could it not be? If this was a low digit, a 1 2 3 4 digit, this would be a 1 2 3 4 digit and we'd have too many 1 2 3 4 digits in the column.
So that's at least a five.
It doesn't doesn't really do anything, I don't think. Um, it sounds like there's now a trampoline wall going on. Let's all go here. Um, oh dear. So, I've still got absolutely no clue what the smelly digit is, where the smelly digit goes really in any number of boxes and or even how to approach this to be honest. This is just it's really difficult if No, that doesn't How do you do How do I do this at all?
Um, okay. Let's try and think about this.
Is it this? Is that hard? Is that hard to achieve? If that's six, how hard does it actually get?
If that's six, this is a hit line.
That is definitely Yeah, we've already done this.
Ah, okay. No, there is more, isn't there? If this is six, how do you get to a count of six?
Because the six itself can't be correctly counted.
And the six is that position, isn't it?
1 2 3 4 5 6. So the six would be wrong.
This would be wrong. The one would be wrong.
Wherever that is.
Or to put it a different way, these couldn't be two, three, four. So not all of those could count. Yeah, you could count two of these and three of these if this is six because the six itself couldn't be correct. And that only gets you to a count of five. So that is a five. Okay, that's been available for ages. Um, now so at least three of those have to be correct because I can't get more than two from here.
So at least three of these have to be correct.
So if that is a one, if that's a one, it's a real hit line, but it can't be a real thermometer as well. So it would have to be a reversed thermometer, which would make this Oh, this is so confusing. So if this is a one, this is real.
I. It's a real hit line, which makes this a one. From a hit line perspective, we don't care what these are. But I can't also make it a thermo. So, it would go one.
This would be seven or eight. And this would be six or seven. It would have to go backwards. This would have to be bigger than that.
Now, does that allow me still to get enough counting there? Can't really see it. That's 1 2 3 4 5.
It take Okay, it does take away the ability of this one to be six if this is a one because if that's six, that will be higher and that will be a correct thermometer.
So, this would be seven or eight.
That's tricky actually. You know that is tricky to make that work because let's just let's just work through this slowly. What I'm saying is I know I know because this is a five at least three of these positions are in the correct positions on the line. So position 6 7 8 9 at least three of those have to be correct. But if this is a one now I must make sure that this digit is bigger than this one. Otherwise, this is not only a hit line, it's a thermo as well. So, this is a seven or an eight and that is a six or a seven. Now, this digit now, which is a seven or an eight, is misplaced. So, I've I've like increased the number of misplacements because because the seven or eight, whatever this is, can't go there, there, or there now.
So, so this one is wrong definitely. And whatever digit this is is also wrong. If this was a seven, you couldn't put seven there. If this was an eight, you couldn't put eight here. So, you're going to lose two of the two of the digits definitely. If Right, we got to be care. Right. So, what this is telling us is that this Well, it's I think it's telling us this can't be a one cuz if this is a one, I can't make this not a thermo.
It would have to be a thermo in order for my five to be correct. So, what I want to do, so this is not a one.
This is a one cuz we knew one of we knew one of these had to be real.
And look, why did we know that?
I can't remember. Oh, because they couldn't both be real cuz they both have one in the bowl. That's why. And I couldn't make them both false because then I'd have too many ones. This is Marty. You've gone completely. Oh, wait.
Hang on. I need to replace the pencil marks here. These are not nine. These are from 678. And I don't think I now know the order at all. But I've just noticed I've got a one here. And I've got to put a one on that line, which is a real index line. So that's a one. And that one is in position four. So that's a four. And now that is not a four.
And or I'm quite sure this does something.
Two, three, and four are now well. Can any of them go there? That would be a legitimate question.
No, cuz that is a thermo. So if I put two, three, or four here, this has to be a one, and it can't be.
So So two, well, two is already on this thermo, but I think three and four are on this thermo as well. And I can write those in. So that is three. That is four.
We probably have to be careful with this being a five and being an index line or something, but that's now a four, which means this is now one, two, three.
Um, further implying that this one has to be smellified.
Oh no.
So this one So this is so weird. This one has to have a smellification. But I still don't know where the smellification is. It could be that one and one of those is a smelly or one of those. One of these and one of those is a smelly. But I know four isn't a smelly.
So hang on. was this line was meant to be a thermo and is currently performing that job manfully. It can't be a hit line because at the moment it's doing very well scoring. It scored four. So, it's not a hit line. But if this was a five, it would be an index line.
It would be one of those perfect index lines where everything is indexing itself. So, this is not a five. So, five is in one of those. Hang on. This is a ah hang on, hang on, hang on. This is a thermo and and the m so the so that digit is five or six just by dent to the fact it can't be 1 2 3 or four. So this this thermmo's got hardly any and this has to be a five because five can't go there.
So this digit I don't know.
Um or at least I've got something in the grid. Come on, silly man. Work out what's going on.
Um this digit is now not countable is it?
So these two could be countable if that is a one.
So 5 2 3 1 1 2 I still have to make sure three of those are counted.
But this thing Oh wait. Okay. I know that this is a false. it. I don't know how it's false in terms of I don't know where the smelly digit is on it, but I know it's false. I know it's not an index line.
Sorry, not a hit line. I know it's not an index line because it can't contain 1, two, and three. So, this is a thermo, which means I don't know what it means. Well, it means that this can't be an eight and that can't be a six. We've got to ascend from here to here.
So So I don't know what that means.
If this was Okay, if that was a seven.
Wait, wait. This is a six. Yeah, this is great. This is I can do this finally. If this is If this is a six, everything can work. If this is a seven, that's an eight. Both of those are missposition cuz that's position seven. That's position uh sorry, that's position six and that's position seven. They both be off incorrect. So, I could only score two. In fact, I couldn't even score two if that's seven. That's eight. Cuz the eight would be mispositioned. So, this is a six.
And now now that's a six. I got to put six in this box. So this digit that digit 78 or 9 just by sedoku and that does give me a 789 triple in this column. So these digits are 235 and presumably that's going to be incredibly important. These digits are 6 6 7 8 not 9 6 7 8 here. Surely that can't be true.
If that's if this is a true hit line.
No. Well, wait. No, no, no, no, no, no. Um, this is a length seven line. So that if this is seven, obviously uh there are not sevenly correctly placed digits cuz this is incorrect in itself. If this is a six, I've got to place the rest of the digits in the correct place. So I could go 2, three, this would need to be a four and it isn't. So this is a lying. The thing is it's lying and therefore it's smellified. But we don't know or at least I don't know where the smellification is is ponging from. It could be from here. It could be from there.
Okay. So, what? Oh, it's not it's not a thermo. Oh, wait a second. This is No, this is very good. This is very good because it's not a thermo cuz this digit's too big. This if this is a 6 7 8 9 10 11, this would be at least a 12.
So, this is an index line of length seven. So, it has the digits 1 to 7 on it and not 8. So, this is 67. No memeing. That's now 8 9. That is now seven.
If these were the wrong way round, if this went 6 7 98, we'd only score two here and a maximum of two here. We wouldn't get to five. So, we've got to go 8 9.
These digits are 8 n probably something that tells us which way around they go. they go.
If they were 89 that way, it would be a thermo, but it's meant is this is only meant to be it's only meant to be a hit line. It's not meant to be a thermo as well. So, it's got to go backwards.
98 7.
Okay.
This this is going to be a thermo, isn't it? So So now ah so now we know the smelly digit is 5, six or seven. I know it's not two or three from this box. So if that is two or three, we'd know that the smelly digit is six or seven, but if this is five and five is smelly, you see that could very well work. That would be smelly. That would be smelly.
And that would be smelly.
So right six and seven here are indexing one and four. This is position one. This is position four. So these two digits are one and four. I actually know the order of these. This is a one. Oh, whoopsie. Whoopsy. Whoopsie. Whoopsie.
How do I get This is a one four pair.
Getting mad. Um, and that must be the one. That's going to give me the order of the six and the seven. So that's a six. That's a seven.
And this this digit is a five because this line has needs to have 2, three, and five on it. And that that has to be five. So this so this is five. So I think five is going to be smelly. I'm not I'm not certain, but I think it is going to be five.
So now, well, hang on. 6 7 8 9 are all correct here. So that's four corrects. So I need either this to be a two or this to be a three.
Uh I don't know. That's fine, isn't it?
Oh, that can't be five. So that can't be six.
That this is a thermo, isn't it? I haven't gone mad there. I know it's Yeah, it's Yeah, it is. Cuz it would need a one in the bulb or one in the hexagon to be an in hit line.
And we can see it's got the smelly on it.
So one is quite close to the hexagon in box thingy thingy.
That oh that's it. Look this digit here is very very high. It can't be 1 2 3. It can't be four or five. So it's at least six on a on a very on a on a thermometer. So that's got to be six or seven. This can't be six now. And this can't be seven now.
I've got an 8 N pair in row seven.
I've got Where's Where's four in column four? Can't be there. It's got to be there.
So this digit uh it's seven or eight is it? Is that what we're saying? That's good if it's true because it'll place six in the column. Um yeah. So that's the question, isn't it?
Where's six in the column? It's got to go there.
So that's six. Six is over there.
Nine in the column is placed. 9 8 9 and ah so right so the smelly is not five anymore because the five isn't here. So this right this is huge.
Nah it's nearly huge.
Right now, we need to do some correcting because the smelly I know is on here and from from somewhere I in my brain I thought it was five, six or seven. Why did I think that?
I mean, it clear I I know I thought this. I think it's cuz it had to be on there.
I I can't really remember, but it's definitely not there actually. But because it was 5, six, or seven, but now it's down here and can't be five. It's six or seven, which means it is one of these digits, which means it's not one of these digits.
But now it's one of those two digits.
It's not this digit.
It's not this digit.
And what does this mean? Who knows? Um, can this be a real hit line?
If it was that couldn't be a one. So that would be at least No. No. I have learned that a four cell correct hit line has to either have a one in its bulb or have a two in its bulb. But the three and the four have to be correctly positioned which they can't be. So this is telling a fib and that means it has got the six or the seven on it and that right. So this line here is a it's not an index line cuz then it would contain these digits would have to be 1 2 and three and we we'd have so many digits in this box that from 1 2 3 4 1 2 3 and four. So this is a thermo and now this is not the naughty. It's not the smelly cuz the smelly is six or seven and this is a real thermo. So one of those is six or seven and is the is the smelly and this digit is oh this is beautiful logic honestly. So this this is a thermo so that's got to be lower than four and it can't be one. So it's got to be two or three. And now I've got a two three pair there. So that's a one.
And now now the two on this line can't be correctly positioned. So the three must be. So that's a three. That's a two.
That's a two. That's a two. That's a three. No three in the corner there. Uh three. Could get three in the corner up there, though. Four is on this line. So this line, this line could be real, actually. May Oh, maybe it is real. Hang on. Hang on.
Hang on.
Because it could be real. 1 2 3 4 5 6.
It would contain the digits 1 to six, which actually it really could be real.
But if it wasn't real, the only way it's not real is if the smelly is a six.
Actually, why do I say that? Because where would we where would we smellify this smelly?
The the way we would smellify it, it couldn't make these smelly because one of those is smelly. So, we'd have to smellify it here, which is in the same row as a seven. So, that would be a smelly six.
Yeah, smelly six might be where we're going. And then that would be No. No.
Smelly six is not going to be our friend.
Well, no. No, I'm not. No, I'm not saying that. Actually, I'm not quite saying that. What I'm saying is that I don't think I think this What I'm saying is this is a real line. So that's always a six even though it might not be smelly.
Wait, no. No. This is fine. This is beautiful. This is it. This is it. I think that I think the smelly is a seven.
Bear with me on this.
For this line to be smelly, that has to be the smellier, which has to be a six, which means that this digit would be the smelly, which we and it would be a smelly six.
So, this would have to be a five to make the thermo work, but it can't be. So, this is not a smellifying six, but that doesn't really matter because therefore, we know this line is a true index line.
So, it contains a six on it. Well, where are we putting that that cell again? So, that's always a six, but now I think it's an unsmelly six cuz if it was a smelly six, it would break. So, six can't be smelly.
The six is Yeah, I suppose another way of seeing that is that six is in one of these two cells.
If six was there, the therma would break. So six is here and therefore can't be smelly. So seven is smelly.
Um and I know seven is on this line. So that is a seven.
And seven is in one of those. And let's let's correct everything now.
So all of those are unsmelly.
All of these are definitely smelly.
There is a seven on here. Now, if the seven was here, I'd have the same problem. This digit would have this would have to be a thermo, and this would have to be a five and a six to lie between the four and the seven. So, the seven has to go here.
This has to be eight or nine.
Apparently, that's not resolved. Seven is in one of Oh, okay. This isn't eight.
I didn't see this, but seven is in one of those. These digits include a three.
They're 379.
Feels like we should be able to do that, but I can't see how to.
That's not nine.
Um, now this line now, well, these are the digits 1 2 3 4 5, which means this is an eight, which means one of those is an eight.
And okay so if but if the one ah yeah if the one was here it would be saying write the two on the index line into the first position where it can't go. So this is a one which doesn't actually it's not going to be very good for us is it?
Now, if the two was here, that would be saying write a five into this position, I think, which doesn't work. So, this is a two.
So, these are 3 4 5. I'm sure we'll be able to do better. Let me just think about it, though. So, these are three, four, five.
Now, if this was a three, that would be saying this was a five.
And if this was a five, this would be a three four pair. That would be a nine.
I don't know. What about that? Oh, is this a naked? Maybe maybe this column actually. Hang on. I need 3 4 5 9.
That's a naked single. That's a five. So that's a five. Ah, that's not that good.
Actually, that five this line. Oh, wait, wait.
I can't make this a thermo. If it was a if it went 1 2 3 4 5 six, it would be a thermo. So, it mustn't do that. So, I've got to reverse those two. This is now a nine.
This is 37.
It's this this is an index line. So, the two and the three there are indexing each other. And I can't use them. And can this be anything else?
Don't know. Uh, nine is being placed up here. So, this is presumably eight now.
Okay. Let's let's get rid of our corner pencils because we we actually are in a position where we can go 3 6 8 4 5 9 1 2 7 and smelly smelly things are sevens.
So, one of those is smellied.
Um, whatever that means. Uh, well, hang on. Hang on. This can't be this can't be both an index line and a thermometer. So, if that's a one, it will be a thermometer.
And it will be an in a hit line a hit line sorry because it will be correctly counting one. That can't be a one. If this is a two, this is a two. It can't be correct. So it would need to have a seven on it.
Am I going crazy?
Maybe I think I'm starting to over complicate this in my brain. In order for something to be I think I've gone mad.
Shenanigans are only caused by smellies, aren't they?
Yeah.
Yeah. So, this this line can't be real.
It just can't be.
Well, it couldn't be real without it being a correct thermo. So, this has to be a seven.
So, this Now, now how now does that have to be a nine? Because this has to meet some criteria.
It's definitely not an index line anymore. So, that's a nine and this is not a seven anymore.
This line could be an index line if it's got three and four. Four, three. And then you'd have to be really careful about not making this a thermometer.
Okay, let's do some more pencil marking.
What What do we need? We need 179 in the bottom row. Oh, that's that's easy. This is naked single. That's a one.
Okay.
This is meant to be Well, we don't know because it could be a real thermo.
Well, it could still be it could still be index. No, it can't. It can't be index. So, it could be hit. It could be a hit line. Um 358. I wonder how many times I've missed the words index line and hit line. I've inter interchanged them um you know incorrectly when I hadn't meant to probably quite a lot.
So these uh okay. So how do we do this then?
If so this line here has it got the smelly on it? That must be the first question. Has it got the smelly on it?
And if it has got the smelly on it, what is it going to be? And the answer's probably a thermo, isn't it?
Probably is.
Is I'm far from Oh, can this be?
I don't know how to do this. I just don't know. I'm sorry. Let's try and do some sedoku, shall we?
Um, one is in one of those cells.
This digit is 1 3 6. It's not. Okay, that's that digit is restricted. Three or six, I think. I'm just going to double check that. 1367.
Okay, so that's three or six.
And this digit, well, it just depends on what the line is. You see, if the line is real, this has to be a four and probably could be. If the line is not real, this has to be seven because it needs something on it to make it not real. So, that is four or seven.
That's bizarre, isn't it?
So if it is seven then we have to decide what sort of line this is and it has to be I mean it looks like it can be a thermo all day long and it would yeah you just have to be careful about it I don't think it would be um a hit N would it? If this is a seven, if this went, if it was seven and it was a thermo, it would have to go 1 2 something 7. That would that would be a correct thermo. But this wouldn't be counting the correct number of hits cuz the one and the two would be in the correct position. So this should be a two but wouldn't be if this is a seven.
If this is a four on the other hand this would be a three four three and then these would have to be these would have to stop this being a thermo.
So this would have to go one, two. So it would be a one, two, three, four line.
I don't know if that's possible or not.
Both of those things seem very reasonable. All right, let's keep going with Sudoki, though. 2389.
That's not nine.
1367 here. 1367.
Is there a line I've not used? He says somewhat desperately. Um I've not really thought about this line down here. But that looks that line looks absolutely fine to me to be a thermo with this being a nine. That's very fine. That would make this a seven.
That would be a four.
Is it some sort of sedoku trick?
Do I know the order of those? If that was a three, that would be that would help, would it? Yeah, it would stop this being real. So, if that is six, that is seven.
Maybe that's a problem. So, then that would be a seven. So this would have to be not a thermo, which would mean it's either Oh, so it'd have to be a hit line, which would mean that this one would be correctly counting the only instance of correct digits. So this couldn't be a three in that situation.
This would be a five or an eight. See, all of these things look broadly possible to me. It doesn't look like I've got enough information. I need a knight's move or something to finish it.
Um, am I being really dense? Chorus of people from Simon's future. Yes, Simon.
That's definitely smelly.
Uh, in this row, what do we need?
Oh, I suddenly thought maybe I got a 2 3 4 7, but I haven't. Five is in one of those two cells. That is true.
What? I don't understand.
I really don't understand.
It feels like there must be some configuration which is going to make one of these lines do too many things correctly.
That's that's what I think. I don't know how to prove it though.
Um I'm sure there is a way probably If if this was an eight, would we care?
No. Cuz if this was an a hit line, we can absolutely put crazy digits on it.
If this was a seven, this wouldn't be a thermo. This would be a hit line.
And the only thing that would I'd have to be careful about would be the possibility of this being a three. So providing I avoided that, I think it would work.
If this is a seven, if this is a seven, this is a nine. That prevents this being an eight. So this would be five or eight.
And this would be a four.
And that would be a five. And this would be a five and loads of things would flurry along.
Okay, so maybe it's this line again. I think that somehow there is a way that we can tell what this line does.
And I don't know what it is.
I really don't. Um, if it is real and it's got 1 2 3 and four on it, it must not be a thermo. So, it would have to be 2 1 3 4, wouldn't it? Oh, that's makes it Oh, that's beautiful. I've seen it now. That doesn't work because that makes it into one of those weird thingies that we were looking at a very long time ago. If this Yeah. So, the point is it I mean that's brilliant, Marty.
Actually, that is brilliant. That's just flamboyant to put that in the puzzle. Is just flamboyant.
I'm a bit cross with myself. I didn't see it more quickly, but it is brilliant. So what Marty has worked out somehow is that he can lead us on this merry dance and at this point he can say, "Oh, look, you've got a possible index line here." But if you do think this is a real index line, more fool you because how do you make it not one of the other things? The point being, if it's a real index line, it only contains 1 2 3 and four. We can see the three and the four have to go there. Therefore, we can't make it a thermometer. So it can't go 1 two. So it has to go 2 1. But then you get this 2 1 3 4 nonsense where that is the correct hitline total because the three and the four are in the correct position. That is absolute genius. So this has got to be a seven.
Thereby making that a seven and this a nine.
Let's hope this does something profound.
These are all the smellies. We have found all the smellies. This is a seven.
This is a three. That's a three. That's a two now. So these don't include three.
They are. That's a nine. Apparently this is a 2 eight pair. And in this row we can take seven out of these cells. 1 3 six. So what are those? Four. Five.
That looks good, doesn't it? That does look good. And I've got a four five pair here. So we can take four out of this one. Five out of this one.
And because this is a lying line, we now have to decide what it is.
It could be a thermo and just go one, two, and then anything.
And that would work. Can it be?
Maybe this always has to be a one.
And this one is Oh, hang on. This one is only capable now of being an in a hits hit line with this being the correct count. So that can't be a three.
And it's still all going to come down to this line, isn't it? I think so. What line is this?
If it's a hit line, we can't put one here because it will then be rendered incorrect by the two being in the correct position.
And if the two goes here, you can't put two correct position digits in it. So, it is a thermo and it's got to go one to something. This is now one by Sudoku.
This two needs to do a lot.
I hope it's going to do enough, but I'm not sure. That's five now.
This is not two.
So that five does the five and the four.
Does the six, the two, and the four.
That does the Okay. Okay. We might be in business here.
This column is done, isn't it? I need to put three in it. Oh, I didn't I didn't get a three in the corner as a result of that.
And this is No, that this this was a hit line. It wasn't allowed to be a thermo. Oh, it mustn't. No, it's not allowed to be a thermo. So, that's got to be an a. It's got to not be a thermo. Positively not be a thermo. There. Now we've done it.
Whoa. Now we've done it. Wow. Wow. That was beastly. Absolutely beastly. I mean, I wasn't help my sister arriving. Bad, Hannah. Um, but to be honest, that's not her fault. It's entirely mine. Um, but but I think even if I'd had a fair wind, I would still I'd still have got in world of trouble over here. And then I probably still have got in a world of trouble over there. Anyway, oh, what's that mean? Oh, that's fine. Um, anyway, I better get I better get off. This has to get to the video. It has to be uploaded. But brilliant puzzle Marty.
Happy birthday, Viking Prime. I'm going to go and put my head in a cold towel.
Thanks for watching. It was right, wasn't it? Oh. Oh, missed. You've managed.
What's that's um the Marauders map.
It felt like Yeah, it feels like I've been on a trip through the Marauders map. Anyway, let me know in the comments how you got on. I enjoy the comments, especially when they're kind. And we'll be back later with another edition of Cracking the Cryptic.
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