Clues that perform THREE Functions - Amazing!

[@joelstevens5670]

Thought I’d put this in a separate comment. For those struggling with the middle part of the puzzle, there is a box skyscraper on 9s - 9 can go in 1 of 2 places in boxes 5 and 8. Since exactly one 9 is taken up by column 6, the other must be in one of the other two cells (row 5 column 4 and row 8 column 5). Both of these stop row 5 column 2 from being a 9, row 5 column 4 by sudoku and row 8 column 5 via the fact two 9s on the diagonal with two 2s would break the little killer clue. This puts 9 in one of two places in box 4, placing 9 in the middle box by sudoku and sorting out the 1s and 9s.

[@scifigrl23]

I don't know why it took me so long to subscribe. Your videos are always relaxing and I enjoy both of your positivity to the puzzles. It brings me joy. I'm amazed you can keep up such a rigorous upload schedule. Take care!

[@longwaytotipperary]

Welcome to the subscriber club! Many of us share your sentiments as reasons why we are dedicated CtC supporters!

[@emilywilliams3237]

It's always exciting for me to see a 1-hour video from you, Mark. There is no way, I think, that I would attempt this puzzle, but I enjoyed watching you work through it. Interesting idea to have the clues serve three purposes - and it worked really well to produce a very interesting puzzle! Thanks for the video, as always, Mark.

[@stevesebzda570]

Yeah, 57 minutes from Mark, I ain't going near it (let-alone three functions). No way, lol. Nice 😂

[@chocolateboy300]

I finished in 142 minutes. Combining multiple clues into a single clue makes for a really clean looking sudoku. Unfortunately, I completely forgot about the 19 sandwich sudoku and spent almost an hour searching for another way. Once I spotted that, it cracked immediately. Great Puzzle!

[@firmbase]

Never ceases to amaze me how Mark can do some of the most ridiculous on the fly calculations and chain logic but then completely miss basic sudoku staring him in the face for 10 minutes 😅

[@ChrisRamias]

Its a big part of the entertainment value of the channel

[@MadsOcto7]

​@@ChrisRamiasit really is 😅🤪

[@spatulamahn]

Same! I wish I had either his or Simon's genius with my scanning ability! Simple rule for me --- If I put in a digit, I look in the box, and along the row and column for anything I can remove or set based on that digit. How he can put a 9 in box 9 and not immediately fix the 1/9 in box 8 is beyond my understanding.

[@stevesebzda570]

It never ceases to amaze me how Mark can see all the digits seeing any one cell (and that's probably all the time spotting naked singles). That amazes me (let-alone three different functions). These (functions) may actually take away from him see all those digits (sudoku)? Lol, nice. 😂

[@masu33]

When Simon does it while also hovering the selection over the thing which could be sudoku-ed... that even seems intentional. But then it isn't. :D

[@LogicMasterSteve]

The deduction of Mark at approx. 38:00 minutes I did with R8C5 instead of R7C8. If R8C5 is a 9, then R4C6 and R5C2 are also 9s - which results in two 9s on the pink 22 diagonal. Thus R8C5 is not a 9.

[@Paolo_De_Leva]

I did something similar. Same conclusion (two 9s on the pink diagonal), but it involved hege bifurcation. Were you able to do that more easily than Mark?

[@LogicMasterSteve]

@@Paolo_De_Leva Yes, I tried to describe it in my previous post: A 9 in R8C5 directly forces a 9 in R4C6 and R5C2 and this is a contradiction. This is an easier deduction than Marks conclusion with cell R7C8 and his contradiction in row 1 - but produces the same result. I believe that at exactly that moment of the solve you need some "more advanced" solving step to move on...

[@Paolo_De_Leva]

​@@LogicMasterSteve Wonderful. I can now see what you did. *By sandwitch logic,* a *9* in *r8c5* locks another *9:* 🔹into the first two cells of *column 4* (r12c4) 🔹into the first two cells of *column 7* (r12c7) *By sudoku,* this forces a *9* in *r3c3, r4c6,* and *r5c2.* This makes this puzzle significantly less brutal and more interesting than I thought. Thanks a lot for explaining. 😏👍

[@Kirbyfan87827]

Finished in 30:38 with help from the video after getting stuck ten minutes or so into my own solve.

[@frankjiang1857]

Finished in 36:08. What absolutely gorgeous logic to be able to use the clues 3 different ways. It was absolutely amazing to run through the logic to get each break in the puzzle. Astonishing setting and a very fun puzzle!

[@sirenier]

being early is great until i realise i can't read comments while i watch

[@piarittersporn]

Two months later ... but with pleasure. Wonderful puzzle.

[@F1r1at]

56:27 for me, could've done it much faster, but I spent too much time thinking about sandwiches contents, instead of trying some other ways to crack it.

[@Rach881101]

44:26 for me. Interesting puzzle!

[@difoolgc5211]

I think that Mark and Simon calming they have a blind spot for giving digit is a case of survival bias, they just as often misses digits they have entered themselves they just doesn't recognise that as often, it took 6 minuts form @38:53 to @45:05, to spot that the 9 in R8C7 sees the 19-pair in R8C5.

[@Mounteban]

Did anyone find an easier way to make progress around 37:00? The logic for why r7c8≠9 felt a bit unsatisfying and I couldn't avoid the bifurcation there.

[@coqui9879]

This is the exact same spot I got stuck at

[@vishvananda]

It might be more satisfying by just attempting to place 9s (I did it with colors): if r7c8 is 9, it puts a 9 in r7c5 and r1c6 (to make the 22 sum in c6 work). This puts the 9 in box1 in r2c3 or r3c3 which puts the 9 in box 4 in r4c2 or r5c2. You can rule out r5c2 because two nines in the 22 sum would break it. This puts the 9 in box 5 in r5c4 which puts the 9 in box 2 in r3c6, ruling out the 9 from r3c3. Now you have two 9s on the 35 sum diagonal which breaks, proving that r7c8 is incorrect.

[@coqui9879]

I figured it out. Instead of looking at that 9, look at r6c7. If you make that a 1, the puzzle breaks, which means it can’t be a 1, which means r5c8 must be a 1 and a lot of the puzzle falls into place from there

[@xavierassfeld7983]

Look at the V domino in Nonet 2. If it is (1,4), both the 22 diagonal from R1C2 to R8C9 and the 22 sandwich in C4 are not simultaneously satisfied.

[@spike5843]

@@coqui9879this sounds good but could you explain a bit further please

[@skasperl]

20:17 That couldn'work. You got three 5s, 9 & 1, but R2C3 can't be a low number. Or am I overlooking anything?

[@skasperl]

Oh. He does the working out at 25:02 and proves me wrong.

[@vulcanfeline]

i could hear this video much better. thank you

[@longwaytotipperary]

Really wish those of us in US could see you on Countdown! Always a joy to watch you solve puzzles - of all kinds!

[@ag9bklnxz]

Fun puzzle! I somehow got away with a 20:25 solve (#253), usually I'm about twice slower than the other viewers/commenters but this puzzle just 'clicked' for me.

[@EmonEconomist]

81:58. A long one - I got very stuck in the middle, and finally got things moving at the end but realised I'd stuffed up somewhere and had to backtrack. But I got there in the end!

[@scambodia147]

Morning Mark,enjoying your prowess on countdown- seems like making the quarter finals is almost there.

[@srwapo]

You have a 29 pair looking at r9c9, but also YOU HAVE A 29 PAIR IN BOX 9! Love how out of the way you went. 😂

[@srwapo]

@44:55, I CAN SEE A REASON THAT DOESN'T WORK!!!!

[@BurnChaos]

Waiting for him to do suduko on the 5s, he finally starts but still misses box 8 and then box 5, and then he says something about how he hopes he's not missing something as obvious "as the 5s" had me over the top with laughter and frustration.

[@psiphiorg]

Quite a tricky one! My time today was 60:06, solver number 76.

[@stevieinselby]

Great start to the puzzle, and I really like the use of look-and-say clues ... but I hit the brick wall on the 35 diagonal and couldn't see how to chain the logic through to rule out the 9 in box 9.

[@Gonzalo_Garcia_]

25:05 for me. Nice puzzle!!

[@ericpraline1302]

This had quite a brutish step, but always impressive to construct a puzzle with so few clues, never mind making those clues count for three different things.

[@Paolo_De_Leva]

Most interesting comments here by *LogicMasterSteve* and *Mounteban,* if you are looking for less intricate logic to determine the position of all *9s* at playback time 38:00.

[@anaayoung9142]

The 2 in boz 4 caught me out of guard. Needed your help for this easy easy thing 🤦‍♀️ But it was a enjoyable puzzle for sure! Thanks for the solve! 😊

[@stevesebzda570]

I think Mark should have left that shading for "19s" in @ 11:02 . Because, those are 19s in box8 (the 3 in r9c4 did that) and the "green" from the "19" for that 22 clue extends from there (you can extend the green in other words) I'll let Mark (the math genius) decide how many . I'm trying lol 😂 EDIT: 15:23 Yay 😂🎉🎉

[@stuartmcconnachie]

47:56 You pencil marked the 8 and 5 round the wrong way. Edit: Actually neither way can be 8 and 5 due to 5 in row 1 and box 9.

[@londov1]

Hello! VoD is an abbreviation of Video on Demand.

[@sirenier]

honestly? i didnt know that- i know what a VOD is but never realised it stood for that i kind of just took it as its own word

[@Tahgtahv]

@@sirenier Yep, that's it's official meaning, for the last 30 years or more, and technically refers to the service provided, such as KZbin, Netflix or any other service that allows you to watch remote video content. VOD also has a secondary meaning to specifically refer to a recording of a live show such as on Twitch or KZbin Live, etc. In this case it does act more just as a reference to a particular file/piece of content, rather than the service the acronym represents.

[@malvoliosf]

“I’m doing it, because I’m crazy.”

[@matthewjohnson6360]

I could see a fog puzzle with the same ruleset.

[@sushirunner]

It seems as if Simon has infected Mark with neglecting the Sudoku. 🙂

[@ayakoa2096]

26:27 for me very fun puzzle

[@ouwebrood497]

I was very far into it, solved all the non-sudoku rules but then it didn't add up.

[@greatgreyowl2583]

missing that placing the 9 in box 9 solved the 19 in box 8 cost him a lot of time.

[@Manigo1743]

They should have been sandwich clues along the diagonals as well.

[@_-_-Sipita-_-_]

28:46 for me. solved it b4.

[@lasagna312]

I agree that Legally Blonde is great and that Legally Blonde 2 is terrible!

[@cbnagesh]

Mark seems to be '9' blind today

[@Pritchie45]

75 minutes

[@ouwebrood497]

I thought I was finishing it and in the end it didn't work out.

[@srwapo]

😥

[@omardiaz6255]

Been there a lot

[@joemucchiello4542]

Is this really 3 different uses? Isn't "Look-and-say little killer" a subset of "little killer"? And thus, the numbers outside the grid are "look-and-say little killer" clues and "sandwich" clues. Usually you wouldn't say something is two kinds of thing and then list a specific thing and the more generic version of that thing.

[@stevieinselby]

Look-and-say is definitely different from little killer, so yes they are three different uses.

[@Paolo_De_Leva]

[Standard] *little killer* means sum along the diagonal. *Look-and-say little killer* means something else applied to the same diagonal. They can be (and typically they are) used separately. The same is true for *killer cages.*

[@joemucchiello4542]

@@Paolo_De_Leva It make no sense that the two share the name "little killer".

[@Paolo_De_Leva]

​@@joemucchiello4542 Yes, look&say *cage* or look&say *diagonal* would be terminologically cleaner expressions than look&say killer or look-&say little killer. And, by the way, even the expression "little killer" makes no sense to me. Is there a "larger" killer? A cage is not larger than a diagonal❗ However, even in scientific language, the same term may have a *generic* meaning and one or more *specific* meanings, depending on context. And in common usage one of the specific meanings (the standard meaning) is assumed if that term is used without specification. For instance, you can use the expression *killer cage* to refer *generically* to a cage indicated by a dashed line. Then you can distinguish between a *standard* killer cage, a *look&say* killer cage, etc. Moreover, in common usage, you can assume that a killer cage is standard unless the constructor specifies otherwise. Similarly, you can use the expression little-killer to refer *generically* to a diagonal indicated by an arrow outside the grid... Similarly, in common usage, *cones* are typically assumed to be right, circular, and non-truncated. But you can also have elliptical cones, truncated cones and oblique cones. Even pyramids can be considered to be cones with non-circular basis❗ Think about it. We might not like it, but this makes sense❗

[@Paolo_De_Leva]

en.wikipedia.org/wiki/Cone