Tutorial #78 Sudoku. The Bug +1

[Music] [Applause] hey everyone here we are tutorial number 78 and this is robin the sudoku guy with yet another bit of fun another hope adventure here we go this is one that i got from the los angeles times and it's one of these puzzles where it's a pattern and some of these patterns are fun to do but this one is not as easy as it looks because you've got these empty spaces here and here and here and here but anyway let's have fun see what we can do you ready let's go first of all we're going to do the basics um tmb lcr and this time if i see something ahead of time like across me i'm going to put it in if you see something do it right there here we go a long cross here first of all um we have one we have two sixes a six here and a six there gives us two sixes in here there's our two sixes now ninety-one seven ninety-seven eight eight and nine there's two nines and in this case we have a nine that can go one two three so i put it for those who are beginners there's a little clue that means they're all going to be one of those one of these cells there's going to be a 9. okay then that's about it for that one i think um just now go to this set in here ones here's the one at the bottom here's a one on the top the one has to be in the middle and there's a there's a one down in here so it can go there and there great twos we have a top two and a bottom two so the two has to be in here somewhere look up and down here's a two here so we can go there and there good um threes well if we got two threes we have a top and a middle it has to be in the bottom down here it can't be here because of that three so this is going to be a big three we make and we're getting we've got a big number finally okay four no fours there at all fives here's something that i'd like to to show i've just noticed with the fives we can do the cross method cross meet method using this block and if i go across there and down here for that five we can have two fives in there so i can put it there and there great pushing right along we were five six there's no only one six in here now i know that six has to be hey look at this here's a six and here's the six that means that if this can be a five six matching pair way to go i didn't see that before uh sevens here we have two sevens a bottom and a top and there's a seven down here so it has to go there great sevens uh eight there's only one eight let me see now eight well here's an eight here's an eight this is this becomes an eight now here's something that i've noticed i put that eight in this row has only got two left so let's put them in while we see it the numbers are four and nine let's look around four now there's no other four and a nine and okay anything any fours and nines up in here but we didn't have much success but we know that it's a matching pair well watch out for that now because of that's a 490 look at this because that's a five six five six matching pair and there's only two cells left this is a four nine as well wasn't that neat okay pushing right along um we were doing now we do the bottom section here we have two ones a one here and a one here that gives us ones in here there's no ones up in here so we can put a one there and a one there okay twos any twos nope only one two okay if i do a cross cross no oh look at that look at this if i do a cross there and down here that gives us a two here and a two there if that that that fits two okay with the two two so it'll work not only being right center left but it'll work also with a uh using the uh cross meat technique okay threes there's only one three three too many spots fours there's no fours at all fives five five five one two three four two many sixes no sixes sevens we have two sevens and we can put the seven one seven there and one seventh there it goes in two spots so we can put it in eight we have two eighths we have an eight on the right eight on the left the eight to have to be here or here can't be in the middle so we can put those two eights in there's an eight and there's an eight well we're doing all right things are happening we're laying a foundation as well what i would say um now uh with the nines let's have a look at the ninths nines there's nothing we can do on the nines um but i'll tell you what though this could be a 9 9 it has to be on this side it can't be there so therefore down in here we could have nines well we could have nines all over the place in here we could so you can do it two ways you can put 999 in or you can just simply say a little nine down in here a little arrow up now it's pushing right along um what about we'll do the verticals this way we have ones ones ones ones ones no twos twos ah let me see ones twos twos threes are all there fours there's two fours four four a four can go here or here good uh fives oh there's only one five but let me show you something here if i take this five and go up to this block in here a five can only be in two spots there and there great that's handy to know sixes we have two sixes a left a center it has to be down in here this becomes a six good well we have two sevenths right center left this becomes a seven now we have two sevens along here this is a top a middle a seven can't be there so it could be down in here you better remember to look that way so you're gonna look both ways when you put a new number in um now let me see we have a six six six seven seven seven eight eight eight is already there nines you'll be nine here well look at this this is interesting see this block here that's the only one left in this block and it has to be a nine so what's the ramification of that we have a right we have a setter nine has to be here or in here those two spots now moving right along we'll take this set of blocks now vertically we have two ones one here and one here and they can be here here or here so i can put a little one here with a little down um and uh we'll make that into an arrow so you don't get confused um twos twos well do you know what i'm going to do here i'm going to do a cross meet uh cross meet with the twos if you take this two and come down here take that two and go across there you've got a two two here now that is really neat look if that's that we know where 2 is going to be on the right 2 is going to be in the center up here it has to be on the left so this becomes a 2. now now i just noticed before and i forgot to come back to it here's a one two here's a one two matching pair so that means that that no longer can be a two up there it comes it becomes a one if that's a one we can have uh what have we got left in here we have a a two and a five well there's a two down in here so that means that this has to be a five okay and this has to be the two fantastic now we have a five five there's five we have a five in here we have a five in here uh the two we got two two two two that's all there what about coming down this way oh look this becomes now a two right center left so that becomes a two and that means that we can get rid of that other little two over here okay so that really helped now now that we look at this now that we have a five here and a five here this can be a four or five matching pair way to go well i never fine that's pushing right along now we've got lots of things that when we did that now let's look at um let's look at something else here eight eight i'm just looking around four four nine when we look at this there's a four 9 here this is also going to be a 4 9 because it's the matching pair only 2 left in that column but here we have a 9 so that can't be a 9 it has to be the 4. and the other one will have to become the nine and one and i see what's going to happen here if that becomes a nine this doubt becomes a four we get rid of that nine becomes a big four wow things are happening here now four now if you go across here we had a four over here didn't we and this four is goes and it becomes a big nine okay now what's the ramification of all that let's look around well when uh here's a 4 there's a 4 there's a 4 in here so we can put a 4 there and there um when i was doing this up right here i just suddenly noticed this it's funny how you miss things here's a three a left and a right that three also goes up there and it goes there to make a matching pair because you see here we have a three four so that makes that a matching pit that's going to be really valuable to know now i was doing nines wasn't i yeah when we put that 9 in here several things here we can do that 9 goes and it becomes a one and this becomes a nine okay bottom top middle now where that nine goes now let's look at oh there's so many things happening here it's easy to miss something here's the 9 on the right here's the 9 on the left we could have a 9 here and we could have a 9 there not down there so we can get rid of this little thing here because it's not three pots there's only two spots now which is great now let's look around a bit more if we can have a look at this block here there's two two cells left the numbers are two three four four and six four and six matching pair again oh i love those matching pairs i'll tell you here we go now let's look at this column here there's only three spices left three spaces left and when i did this down in here the three i missed the three here two look here's the bottom here's the top you've probably been yelling at me hey robin you missed a three there there's a three there because there's a three up there oh see i missed that before when i was doing the bottom section got carried away it's easy to miss but we found it no worries push on not the end of the world okay we were doing this column here weren't we three four and six well this is interesting this is a three there's a four there so this is a three sixth okay that four that four there means that there's a four here and a four here now going up this here again we have four sixths there here we have a six so that is a three four so three four well we did a lot of little itsy bitsy's there but it's really coming um let's now oh look at this remember we had a 9 and a 9 and we said a 9 would have to be in that in this section here but the two is already there and the three bars are already there and when it's part of a matching pair you cannot put any other little numbers or big numbers there so therefore this becomes the big nine that was a great discovery well yes it's exciting when you realize there's things coming together like that so we have a top a bottom and a middle now we have a well listen look look at this look at the top row can you see something there if you look carefully you can see we have a matching three-fold now one of my previous uh tutorials i mentioned i've did a whole section on this if you have a matching pair plus two empty cells in the same row those two empty cells become guess what another matching pair and it turns out it's going to be one two three four five i've already got them there five and an eight here's your matching pair now let's look down look at this there's an eight there so that becomes a real five and the other one will become your eight isn't that fantastic top middle that's good so this becomes an eighth now let me see that's interesting now we have uh something that i missed down here i think yes you know you see it as you're going oh i didn't get back to that eight eight this is an eight and that is a possible eight matching pair again okay dear and here we have we've only got three spaces in here it's a one whoops let me see now now we have four no no there's more than that no forget that i'll come back to that perhaps um let's take this seven seven seven seven seven take this row here we have a six seven eight and a one one six one six seven eight yeah one six seven eight well we could have had a one in here there's no ones down in here i think we could have had a one in there and then over here we could have a there's a one here so that would be a s six is already there so that's a seven eight and this won't be what's left here this one this one could be a one and a seven eight okay eight eight eight okay because of this we've got the seven eight that means oh boy it's interesting okay continuing on here here we have a true a triple or a three by three a one seven eight and this could be a one and this could be a seven well that's interesting isn't it now it's it's funny when i looked at this can you see i can see a danger danger or some people call it a unique rectangle the rectangle is made up of the seven eight seven eight if we're not careful we're going to have a situation where there's two answers to the puzzle and that's a no-no there's always only one answer to a puzzle and the way to overcome that problem seven eight seven eight is to make this into a one and i've got i've got a tutorial much earlier on that so let's do that and see what happens if this becomes a one what happens well along here that one goes that one goes and this one goes leaving a seven if that becomes a seven we have a middle top this down here becomes a seven okay that becomes a seven we can get rid of this little seven and when i put that 18 i forgot to get rid of that little eight so this now becomes a six oh okay wow things are happening here okay now we've got this is interesting we've got um here we've what do we got we have a one one could be there and one could be there one one one uh one could be a three could be there is there a three down here no three could be there and a four could be there and uh one and a one four can be there well here we have again another three by three a one three four triple triplet it's really important to to to chat on check check on that if that's a six uh what have we got down in here with this four now no it's not no no that's not going to help us now we're at the stage where i'm going to finish off all the little numbers to save time be right back well folks i've now added the extra little numbers to save time but you know by doing that i was looking at the puzzle and i suddenly realized that i've missed some ramifications when i put that seven in i should have made this an eight okay if making that an eight will really finish off that whole row now okay if that's an eight watch what happens if that's an eight this now becomes a seven because that eight goes and uh that seven goes and this becomes an eight and that's something i missed before and i'm glad i stopped to put on the extra numbers because i suddenly realized what i'd miss here let me check right left center yeah perfect now getting back to here when i put this 5 in and this five there's two fires that had to go in there and it's interesting to note that if you look here very carefully at this row down the bottom that's the only place a five can go what does that do that means that this becomes a five and we can get rid of that other five and now we have a one nine wasn't that interesting now let's look at this five five one of these is going to be a five that fits perfectly okay now we're at the stage where i'm going to introduce you to something that i covered some years somewhere actually several years ago but i'm going to revise it again it's called the bug plus one now if you look before i start on that one have a look at all the numbers in the in their cells is there something interesting or something unique that you can see have a look at that my sweetheart's nodding your head up and down what about you if you look really careful every one of these single cells except for one is two little numbers only now that could be a problem because what do you do do you guess try not to do that if you can't help it but there is one cell just one cell that's got three numbers and this is what we call the bug plus one i want you to look carefully at this here we have um well by the way i just noticed too when i was doing these numbers that we have a a one four nine triplet there as well that's neat um but anyway bury bear this in mind all these little numbers cells they've all got only two numbers in them a lot of them are matching pairs but this one's got three now this here is a triple one one three and a four now what you have to do here is that you look for a small number that appears in each one of those cells that's the first step very important and the number is four you follow four four or four the next thing you have to do there's two things you've got to look for look for a number that's repeated in each cell the next thing you've got to do is to look for a cell in this case it's the only cell in the whole puzzle that has three little numbers including the four and that's this one and what you have to do is you can try putting the numbers up in here and guessing up there it won't work but if if you put a four here in place of that make this a four let's see what happens both plus one you're two things uh a triplet a number that appears three and three cells and a cell that has three little numbers so this now we're going to make it a four and watch what happens this becomes a one okay that one disappears with that one and this becomes a nine we finally got our nine and that nine goes so we now have a four because they're all by value cells by value if that is a four this four goes and this becomes a two okay if that two goes this two goes and this becomes a one okay now let's look at the four if this four and that four because we put that four in this becomes a six and therefore that was a plan this becomes a four here we go and if we have left right center right center left now we have a three six three six well when we put that four in that made this a three right so that 4 goes this becomes a 3. okay if that is a 3 that 3 cancels this 3 out down here and this becomes a 6 and if that goes as it becomes a 6 this becomes your 3. okay just let me double double check here 6 6 6 great three no that's whoops i've been t and i was you know you're probably yelling at me by now that's a three okay now we have three three three that's all correct now this three means that that three goes and we get a four okay if we get a 4 there that 4 goes and we get a 3. things are really happening here aren't they now let's push on let's have a look over here this nine means that that nine goes and this becomes a five okay if that becomes a five this becomes a 2 5 goes and it becomes a 2. see what happens when you go by value yourselves oh boy by value meaning it's only two little numbers there here's two this two now has to go and it becomes the sixth okay okay and that six has to go now in this cell so this becomes a nine okay nine and because we got this six here oh because we got that six there um well i can see all kinds of things happening here now uh four four four yeah that's correct that six means that this becomes a five and this becomes a four if that is a four this becomes a five if that's a five this becomes a six if that's why oh you don't believe it we solved it fantastic why because we discovered uh the boat plus one and we discovered a danger danger so let's hope you learned something from this one can't wait to show you some more so bye for now

Channel: Sudoku Guy

Views: 48,016

Keywords: Sudoku lessons, sudoku tutorials, sudoku techniques, sudoku tricks, sudoku hints, sudoku for seniors, sudoku for the frustrated, sudoku for the family, sudoku, sudoku for beginners, sudoku for advanced, sudoku for dummies, how to solve sudoku puzzles, how solve sudoku, brain fittness game, learn sudoku, watch sudwatch sudoku being solved., Sudoku Instruction, Learn sudoku step-by-step, learn Sudoku, Sudoku instruction, easy to understand sudoku

Id: PEqzR6ti4mo

Length: 28min 25sec (1705 seconds)

Published: Fri May 21 2021