The Easter Miracle Sudoku

[Music] thank you hello and welcome to the Easter Sunday edition of cracking the cryptic in a very happy Easter to you all um and we've got a very very special puzzle for you today it's called Miracle Junior and this harks back to the days when we when we well when I tackled the original Miracle Sudoku which only had two given digits in it now this puzzle has well it has a 50 Improvement it has got three given digits nothing not a huge number of digits you might say um in a puzzle uh and this puzzle by the way is by just curb which I think is a makes this a debut on the channel for just curb um but the really interesting thing to me about this puzzle is that the miracle Sudoku had a nice move constrained a king's move constraint and a non-consecutive constraint this puzzle has a knight's move constraint a king's move constraint and then a no domino in the grid can contain digits summing to 5 or 10. so there's no none consecutive constraint now the non-consecutive constraint is hugely powerful so this feels to me like this has been a bit of a trade-off we've got an extra digit but the setter has given themselves quite a Stern test in terms of this um no Domino summing to five or ten rule um and the test to say this is a really really beautiful puzzle so if you're a fan of miracle sudokus and why on Earth would you not be you must have a go at this one um I'm sure we all have a bit of spare time at Easter don't we um now what can I tell you about before before I kick off and have a have a crack at the puzzle um we've got our nightmare Sudoku hunt of course oh actually no actually I'm going to segue there um we do we do have a nightmare Sudoku hunt available now but one of the uh Constructors behind the nightmare constraint that features in The Nightmare on Sudoku street is Riff clown and today is Riff clowns 60th birthday so riff clown many many happy returns my friend um what what a well what a prestigious age you have reached um and what an absolute Diane of the soloku community you are the feedback back we've been getting on this hunt has been absolutely lovely people are loving it so what is the nightmare constraint well actually it's it's basically at the idea that cells separated by a a night's move in chess cannot sum to 5 or 15 in that hunt and there are 19 puzzles on it in all I've been astonished frankly by how many of you have actually solved all 19 already but yeah that is available for anybody who would like to to solve it over on patreon right now where you can support the channel and we are so grateful to all of you patrons who do that many many many thanks um oh and by the way riff clown the reason we knew it was your birthday is Susan wrote to us about it so you can thank her um the only other thing I wanted to mention is last month's Patron award where I still I'm still working through the names of successful solvers of the whole of Alice in Sudoku land so well done to the following people Martin Arts Harrison beer lenault metrop Sam path Kumar Jamie Parker is Stuart Emerson Matt Farrell and Dr lucasen's lions uh Heather trout uh Dan Friedman who asks if at six feet nine inches he's our tallest viewer I'm not sure you are actually because um Tall Cat I know is a very tall cat indeed I'm not sure if tall cat beats six feet nine but he might do um let us know if you're a tour if if you beat uh if you beat Dan Friedman's prodigious height um also congrats to Alex Miller Simon Lauren Paul's purple woof Eleanor godward Parker Bond and Steve Newbold you all sold the whole thing correctly fantastic work one and all now I'm going to read you the rules of Miracle Junior I don't know I don't think this is meant for junior junior solvers um the tester certainly didn't say that I don't know why it's called Miracle Junior um but these are the rules normal sudo Google Supply I.E place the digits one through nine once each in every row every column and every three by three box so normal Sudoku rules cells separated by a king's move in chess cannot contain the same digit so let's let's use this three as an example so if this three was a chess King basically a chess King have moved to all of those cells so none of those cells are allowed to contain three now many of these cells could not have contained a three just because Normal Sudoku rules prevent it so all of those cells would already not have been able to be three but you can see that there's sort of an immediate diagonal constraint that kicks in and effects so that we couldn't have three in any of those yellow cells which obviously the one is one of those but um that's how King's move constraints work now next cells separated by a nice move in chess cannot contain the same digit so let's put uh let's put a five in the middle of the grid and if that was a chest night it could jump to all of those cells and therefore none of those cells could be a five so we cannot have the same digit at the Knights move apart in this puzzle otherwise we'll get it wrong and that's not the idea um so let's delete all that and now domino in the grid can contain digits summing to five or ten so let's think about how that might work in relation to this three that we're given basically that means that we can't put 7 into any of those cells because if we did we would make a domino that sum to 10 and we can't put two into any of those cells because if we did obviously that Domino there would sum to five can't put it there either because this Domino would simplified where we could put the two was there because that is not a domino that is something else I'm not sure exactly how I describe it but it's not a domino so there we go do have a go at the puzzle the way to play is always on cracking the cryptic is to click the link in the video description and you'll be taken to a page that looks identical to this one where you can play the puzzle on whichever device takes your fantasy but now I get to play Let's get cracking I haven't done I have to tell you this although we have a miracle Sudoku app um and I made puzzles for that and obviously sold I solved a lot of puzzles in testing it I haven't done a miracle sudoku for a very long time so I'm going to be out of practice but I I'm in my Temptation here is to look immediately at where three can go and possibly one in the middle box because because the knights move and the King's move constraint are just massively powerful in fact in fact the three is a good thought because the three is also affected by the Domino rule so where does three go in the middle box well let's let's rule out the Sudoku cells first none of those can be a three now let's rule out rule out the king's move that cell can't be a three now let's rule out the knights move neither of those can be a three now let's rule out the dominoes summing to five well that rules out that one because three plus two is five and that only leaves one cell so we get a three immediately in the grid and I think what we should do is immediately try and propagate the threes so three well three is obviously in one of those three cells but it can't be here for two reasons firstly the knights move secondly the Domino so three moves down here three in this box can't be in those cells because of the king's move in Sudoku Knight's move takes care of those so we get a three and one of these two cells three's got to be in one of these four four positions now often I would not corn a pencil Mark threes in such an absolute uh Congregation of cells but in Miracle sudokus it often pays to do ludicrous amounts of pencil marking because there are so many surprising constraints I mean let's let's pencil Mark three in this box uh actually no that's not really gonna work but okay it's in one of four places I'm still going to pencil Market [Music] um yeah now here's a mildly interesting thing about box seven where does three go we've got a pencil mark up here so three is not in those cells but because of this pencil Mark we can't put a three in either of these two cells either because either of these cells because of the knights move constraint would take care of both of these and Frank them in a nasty way so three is actually I don't know ah look look look look that three sees what right so three is in one of three positions only which knocks it out up there and that might not be good enough um well three in box nine I think we're we're tilting at windmills a bit with that three can't go there and I Can See For example it can't go in either of those two cells oh no no it can go in this one I'm wrong it can't go in that one because that will see this cell this cell this cell and this cell can go in that one though because although that wipes out all those those two would be legitimate wouldn't they so I think it's got an absolute yeah it's got a multitude of places it can live I fear in box nine and the response to that is the standard one bobbins um but okay I'm going to I'm going to change tap then I'm going to look at one in the middle box because I can immediately see it can't go anywhere apart from there those are ruled out by Sudoku those ignites moves away and that's a king's move away so we can place one here which means we can uh look look yes where does one go in row five well it's in one of these three cells by Sudoku but these two see that one because of the ludicrous rules so this is the one uh let's try one in box eight boom boom boom boom we're getting quicker at scanning this that's going to be the same isn't it so one is sort of overlapping with threes up there in the corners um okay oh dear no I might I might be about to get very badly stuck I fear I really might be hang on hang on hang on what's going on one is in one of those cells one oh dear come on I would actually actually know this box must be the one must be restricted because this one does look in to some extent um okay one is in one of three positions yes and this is good okay so what the way to do this quickly actually was to switch Tack and rather than look at boxes was to look at rows and we could have asked and I should have asked probably where does one go in row seven because this one is awfully powerful it rules out all of those cells through a combination of Sudoku Knights moves and Kings moves this one sees that one that one sees that one so one is in a app is in a surprising Domino and it is a surprising Domino but it's not a very useful one no okay oh I've got something ah right okay this is Classic this is classic Miracle Sudoku nonsense where does one go in box two and the answer at first blush is in an awful lot well at least three places these three this one pokes in and knocks those out but now look we can ask the same question about Row three where does one go and the combination of all of these various things means it can only go in one position exactly and that knocks it out of here by Sudoku and there by Knight's move so one is in one of these one is here exactly that's going to do some damage now this is doing marvelous stuff like now look at where one goes in box nine one position left that knocks it knocks it out of this one so one's in one of these so this isn't a one so that's the one and I've noticed also that this three pencil mark up here knocks this out from being a three so that's become a three and let's just give this a moment can we do can we do any more miraculous stuff okay I don't know I mean we're left with I think we've got seven ones in the grid so we're left with ones in that Arrangement which we're not going to be able to break up from the digits that we've placed so we're either going to need something like fours to displace these ones or something like that or just another digit we need another digit to get placed somewhere in those dominoes to break up this pattern of ones and what we haven't done yet is thought about two either so that's probably the next Port of Call where does two go in this box well by Sudoku and all of the various constraints it's pushed into the bottom row which is ah I've just had another thought actually which is not very useful here but let me let me tell you what the thought is and the thought about twos well it's going to be relevant up there the two could not go in either of those squares because if it did it would put the three in the other cell and create a domino that added up to five so we do need to be a little bit Yeah in fact look oh that's that's it I'm going to come straight back down to box eight how could this be a three if that's a three it will be next to a two on one side of it and it will create a naughty Domino and we mustn't create naughty dominoes so that's a three um okay so that's push push three down there which makes this a three and that means this can't be a two because that would create an naughty Domino this can't be a three it's too close to this three by King's movage so that becomes a three that knocks three out of here oh right look where does three go in column seven this three rules the roost out of those cells and that three rules the roost over those cells so let's actually only one place for it and we and look we get left with a similar pattern for threes that we've got left for ones but I'm sort of hopeful that we might be able to resolve this now let me just think about this for a second um ah yeah well okay I can't resolve that but I can ask where two goes in this row and these pencil marks tell me there's a two in one of those cells but we can't put it next to the three without creating naughty dominoes so that's a two now Knights moving King's move and not make creating naughty dominoes here puts a two here which puts a two there because these would be chess moves away so now surely yes okay now this would create a naughty Domino if we put two there so two goes in this is y and a sort of Miracle sudokus are just they really are fun to solve again look where does the two go in this box it's got to go there and now well that's not a two so this is a two that can't be a two of the kings move away so that's a two that's a one by pencil marking and we have done all the twos in the grid we have now done all the ones in the grid now all we've got left to do is these threes then we can do it don't create naughty dominoes there we go all the threes are done so now now is going to be a question well literally we've got to totally rethink our strategy now because we have literally finished the ones twos and threes in the puzzle and we've got to place fours fives sixes sevens eights and nines so what are the very restricted digits I mean cells like this obviously can't be eight or seven now because that will create ten dominoes which are naughty uh hang on a minute let me think about this so the two the two was affecting the three and the eight the threes have been placed the two has one digit it now affects the one has two digits it now affects because it still affects fours so fours and nines can't go next to ones and threes did affect twos but now they can only affect sevens so I feel like it's fours and nines that are now the most restricted neither can go next to a one um now I'm just thinking about this now so do we I think what I'm going to do is I'm going to highlight all the cells that can be fours and nines so that's basically that's going to be a lot of cells there it's going to be anything that's not orthogonally adjacent to a one I think this is not actually going to work is it even with the profoundness of this constraint uh well okay box four is about actually box four is much better because it's got three cells that would be orthogonally adjacent to ones so actually um no that might have just died died in immediate death there's literally no constraint Oh No actually that's a one so so there is a small constraint we can reduce box five to a w pentomino um box six isn't too bad that cell yeah okay let me just double check this am I oh hang on that cell it's next to a one why have I highlighted that one I was so that's so disappointing I was about to get rid of this one from being green on the basis that it would rule out greens entirely in box six so imagine that was a four um ignore this one if that was a four you couldn't have actually placed four anywhere then in box six but obviously actually because it's next to a one already it didn't deserve its Greenly status so it was it was punching above its ways um oh we've got two cells there in box nine uh this this I think is a Fool's errand I'm afraid I don't think I'm doing the right thing here [Music] let me just mull this over is there any cell now in the greens that would rule out green from another box so I'm thinking you know it's almost cells like that one because that obviously gets rid of these two but it doesn't get rid of this one so I think that that's okay that's okay that's not that's not okay okay so that cell can't be green because that would rule green entirely out of box eight owl bobbins no that can't be green because it's next to a one and what do you do you see this is what I'm gonna have got wrong here let's just double click all the ones now are any of these ones orthogonally are next to a green no alright so this is better right okay that is much better actually because I have now noticed something I've noticed one thing I've almost noted oh I've almost noted two things I'll tell you right the one thing I've noticed is in this column there's only two green cells so those two squares have to be the four and the nine in this column now we've almost got something similar in this row look in fact aha right yes this is where we're going to look now because that digit whatever it is let's um let's give it its own color we'll make it blue so what whether this is four or nine where does it live in row eight now it can't be here because it would be in the same box as itself and it can't be there it would be a night a king's move away from itself so it's only possible cell is that so that is now whatever this is and then by Sudoku it's there and now it's in one of these two hang on hang on it's in one of those two which means it's in one of these three one of those two one of these three so yeah okay I think we're gonna have to be quite careful here um I'm actually going to highlight all of those cells as possibly blue just to show you what I'm thinking um in this box now where is the blue digit it's not there it would wipe blue out of box one it's not here it would white blue out of box one so blue is in one of those which means blue is in one of these and that's about as useful as chocolate teapot isn't it ah you rotten thing sorry I thought that was going to be quite profound [Music] um okay well let's let's instead of that let's think about this digit then let's make that yellow so where's yellow in the world of yeah that's good where does yellow go in this box now that's got to be yellow and now all of a sudden look that cell has lost its greenliness because that cell can be neither blue nor yellow so that's that that one we can take out of the equation where does the yellow go in this box it's got to go there by Sudoku that takes that one out of the of the the panoply of greenliness is um right so yellow is in one of those two squares again that's that loses its greenliness yellow has only one spot now in box four because of these yellows and these yellows and the fact that these two see each other so this is yellow which is nearly going to be useful oh right hang on hang on hang on where does yellow go in that box and the answer is I don't know but it's definitely in there look so yellow is placed in box six and that places yellow in box five and that does it doesn't seem to place yellow somewhat amazingly it doesn't seem to place yellow in box eight that is ridiculous this is still in two places that loses its greenliness because that could be neither green nor yellow now these both you lose their creaminess okay so it might actually be worth getting rid of the greenliness now I think because effectively we've plotted the positions of um blues and yellows haven't we these are all of the possible cells now I'm sure I'm sure there's going to be ways we could do better actually let me just give that a second or two's thought um no no that would be that would be more a Tigger bounce than a night's move wouldn't it so oh well hang on hang on hang on those can't be that can't be yellow it's too close to this one so that's yellow aha right so that is useful so now this has become well all the yellows are done we've just got all the yellows I just missed this connection here so can we finish off the blues that's going to be the next challenge and the answer to that where where have we definitely got blues we definitely got these three blues I've got a couple of dominoes nah okay I don't know actually so this column then is that what we're meant to think about now what have we got we've got five six seven and eight so oh nearly oh yes done it okay I've done it where does seven go in this column that's the question we should have asked that's the I could have asked that question a while ago where does seven go in this column it can't go in a Cell that's orthogonally adjacent to a three because it will create a 10 Domino so seven is exactly there look bobbins I should have seen that before so seven is now in one of these two cells let's see if we can let's see what damage we can do with the sevens of the world so seven is now not there because it would see both those sevens so seven is in one of those three don't forget it can't be in a blue or a yellow Square unless the blue and the yellow Square have there's more than one of them in a box okay so let's have a look maybe yeah okay let's have a look at seven in this box because it can't go here by Sudoku and it can't be orthogonally adjacent to the three so it's in one of two places and that places it rather beautifully in box five because it can't go there make it make an already Domino it can't go there it would make a naughty Domino so it must go there taking away a blue cell so that forces this to be blue which forces that not to be blue and the seven runs the absolute rule over this box well nearly anyway it puts the seven in one of these two cells seven is now in one of these two squares inbox three and then they both rule out this one if there was a seven in either of these it would see that through the the chess constraints so that becomes seven which means seven can't go next to three so that becomes seven and seven can't go next to three so seven is in one of these two cells in box one knocking it out of here placing it here which knocks that cell out from being blue again so this is now not seven that's become a Seven knocking this one out from being blue placing blue there so all of a sudden look let's double click these sevens and see if we can finish soft sevens now that's ludicrous oh no no it's not it's fine this happens that one that's about to be very upset that puts seven there which knocks it out of here which places it here oh okay and we get left with a naughty naughty sort of unfinishable pattern of sevens okay but that was very cool so sevens are now very nearly done aren't they and we got some blues as a result of that although somehow or other Blues still seem to want to not be finished which is really weird okay let's try let's try let's try eight s then actually I say eights I'm not sure I like the look of eights very much I'm just trying to think about what's affected by the negative constraint though yeah I am going to try eight because of where it can go in this box actually because it can't go in any of those squares because it would be next to a two and make a naughty ten Domino so eight is in one of two places yes eight is in one of two places over here and eight is in one of two oh that's done it that's done it look look look look so the eight in this box is in it can't go next to a two and it can't be on top of a yellow because yellow is a four or a nine so eight is placed and that knocks eight out of here which places eight here which makes this cell you've guessed it not blue so this is blue that's not blue therefore so this is blue that's not blue um that's seeing that cell I think I could have done that before but didn't see it so all my Blues are now done and I suspect we can go absolute Ham on eights now yes where does eight go in this box by Sudoku it's got to go here where does eight go here it's got to go there remember we can never put it on a yellow or blue cell anymore so that's become an eight um that's becoming eight this has become an eight now this is where it gets terrifying doing these puzzles because if you've made a mistake it will quickly come and bite you um fives and sixes now so fives and sixes the only thing affecting five is nothing basically so sixes can't go next to fours um which is presumably in some way going to work and be important but I don't quite know how yet yes I do yes I do let's look at this box because that by Sudoku is a five six pair now therefore if this was a four if yellow was a four it will be making a naughty Domino with a six in One Direction or another so yellow has to be nine and that means that blue has to be four and now where does the six go in that box not next to the four so that's six that's five that's six that's five that's six that's five that's five that's six that's six oh the seventh is still not fixed that's weird the five and six go here five six go here six gets pushed into the corner correcting the sevens giving us the five here and I think I've just flooded with a finish it wasn't that absolutely beautiful what a great puzzle just curb that was that was really interesting so it was it was a classic Miracle uh in the sense that there was all sorts of absolute nonsense you could do in the grid with these crazy patterns um but it had a bit of depth to it because even after we got quite far with ones twos and threes we had to use coloring or I had to use coloring at least to do fours and nines and then it was sort of sevens and eights and you could keep you could keep sort of generating New Logic um and then we finished with a flourish I absolutely love that what a delightful way to spend Easter 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 [Music]

Channel: Cracking The Cryptic

Views: 53,604

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Id: lgEkM-vUR88

Length: 34min 58sec (2098 seconds)

Published: Sun Apr 09 2023