Lesson 26 Sudoku For Kids LCR

foreign the Sudoku guy welcome to the second lesson last lesson we looked at horizontal blocks where we looked at these blocks of nine across this way this way in this way and we were using the principle of top middle bottom to work out where the numbers went each of these blocks has a top and a middle and a bottom now today we're going to introduce you to another step to solve these puzzles and it's called the LCR and you may wonder what does that mean well it refers to left Center and right I'll explain that more in detail later on but let's get going and solve this puzzle we'll go through the same procedure as we did for the last Puzzle first of all we look at ones there's only one one so forget it twos all the twos are there top middle and bottom so forget it they're done threes there's only one three no three here or here so forget it don't worry about it fours there's only one four there's not one here or here so forget about it fives there's not one five there so we'll push on to six now there are two sixes we have a six in this block on the bottom we have a six in this block in the middle therefore this block that doesn't have a six it has to be on the top and there's only one place for it to go and that is there let's do sevens now we have two sevens we have a seven on the bottom here in this block a seven at the top here therefore a seven has to go in here so we put a little seven there and a little seven there and now we come to the next important step we look down the column to see if there is a seven because you can't have two sevens in a column and yes there is a seven there so that cancels out this seven so therefore this seven becomes the real big seven eight there's only one eight forget it nine there's two nines there's a nine on the top in this block there's a nine on the bottom of this block therefore top bottom it has to be in the middle so this becomes a nine look down there's no nines here so we're fine um let's now go to these three blocks ones to begin with well we have a one on the top here in this block we have a one on the top here in this block therefore we need a one in them well here we have a one on the bottom of this block sorry and therefore in this block the one has to be in the middle and there's only one place for it to go and that's there oh that's neat next go to the twos there's only one two forget it threes we've got all the threes bottom middle and a top fours we have two fours a top and a bottom therefore the fours need to go over here so you can you can do it two ways you can do four four four and then look up and down well let's do that if you look down here there's a four already so that cancels out that four and if you look here down there's no Force but here when you look up there's a four there so that cancels out that four so the real four will go there let's look at now at fives we have a five here and a five here a bottom and a top it has to be over there in the middle so we put all two little fives there little five there and there and I look up and down there's no other five so leave it for the time being sexist well here we have two sixes we have a six on the top in this block we have a six on the bottom in this block and we have a six needs to be in these two cells so we can put two little sixes in but if you look upwards here you'll notice that there's a six already in that column so that cancels that six out this becomes your sixth big number sevens there's only one seven okay eight I don't see any Eights nines there's only one nines one nine so we push down down to these three horizontal blocks take the ones we have a top a middle and a bottom done forget about it fixed twos there's no twos there's no twos in either of these three blocks threes yes there's one three that's not good enough we need two of them four we have two fours the top here and a bottom here so therefore the fours have to go in the middle now we'll put a four in here a four in here and a four in here and we look up oh look here there's a four there so that means that this cannot be a four we've already got a four but those two could be because there's no four up above them so this it's all we can do is for the time being it just stays little numbers um fives there's only one five I think six yes this is an interesting one we have a bottom we have a middle and we have a top and now if I put a six it can be anywhere any one of these three but when we look here up here on this column that six is cancels out this one and we look to take this six here and go up that 6 cancels out this one which means that this has to be the real six because the only one left sevens there's two sevens a middle a bottom therefore in this one it has to be on the top there's no seven there and it has to go there and eights there's two eighths we have an eight on the top here we have an eight in the middle here therefore in this block the eight has to be in the bottom so we do an eight there and an eight there and look up oh there's no weights on either of them so we keep the little H there now that's completed what we learned last lesson but now we come to the next step the left Center and right it's called LCR left Center and right what do I mean by that and there is these are vertical columns and they have a left row or column A Center column and a right column similarly here a left column center right right column same over here and we're going to do it this way Watch How I do it once again we'll start with ones and go up to nine let's take the ones we have one on the left one on the center and one on the right done fixed don't worry about it two there's only one two in these three blocks threes well we have two threes we have a three in the center we have a three on the left therefore the three has to be over on the right in this block and it there's only one place for it to go so it replaces that four and this is the neat thing when you put two little numbers in once you've done that you know that that has to be a four because we figured out that's the only two places a four could go what about fours well we have two fours now we have a four here Center a four on the left so therefore up in here a four has to be on the right well there's only one place for a four can go if I put it there and there I don't want to work with it so we will rub that one out because there's a four over there so this becomes the four okay pushing right along fives we've only got one five don't worry move on six is we've got our sixes well look at this we have a right the left and a center uh sevens we've got our sevens fantastic what I wanted to point out to you is this word up here see that word Ram when we do the vertical we look to see if whatever number we put in what does that lead to in terms of another number and let me show you something here and let me see what new numbers did we put in we put in a nine that didn't have any effect because we've got all our nines there now the four oh this four had a ramification look if you look across here that 4 means that you've got a four in the middle here now four four four because top middle and bottom now that four is very valuable just because we looked at for Ram now we did did I put a new three in did that help us at all no it didn't what is another new number that I put in I put in a three here we've got that number but that didn't have any ramifications force and that four finished up these three fours so we're we're doing all right let's take the five we didn't have anything with five sixes we did the sixes sevens sevens are done nines this is interesting look at this here is a here's a left there's a right this block doesn't have a nine and it therefore has to be in the center so it will go there okay pushing right along now we'll do these three vertical blocks and include Ram as well let's take the ones well here's a one in the center here's the one in the right whatever goes in this block has to be on the left and we could put it there or we could put it there but guess what we look over here and there's a one already there so that cancels out that one this becomes the one and now let's look at the ramification of that one we have now two ones in this horizontal section one one a bottom and a top therefore there's got to be a one over here in these two little ones now let's look at look down same same principle you look down oh there's a one here so that cancels out this one and therefore this one becomes the one was that ever Nate saying the ramification of that you know sometimes you can go right around the whole puzzle filling in numbers just because of ramification knowing using the the top middle bottom and LCR left center right system I have just noticed something and that is in this row we've only got one cell left why not fill it in what would it be that's counted up one two three four five there's no Note 5 so we'll put a five there and now that block has only got one left in it what number would that be one two three three is missing now when any ramifications of that one yes look at the ramifications of this one uh bottom middle this has to be a three wow what a difference it makes when you look for ramifications now what I was up to doing down here we got up to two we we had two we have this block has got a two where you're in continuing on with a vertical vertical blocks this one's got a two this one's got a two that's the left that's a right that's the center this one has to be on the left and there's two little ones I look this way in this way there's no other twos leave them small for the time being threes well here's a three and there's a three a right a left therefore it has to be in the center so this becomes a three now is there any any ramifications of that no there isn't because we now got all the threes across Fantastic Fours fours are done we have a center a left and a right fives we have one five that doesn't help us sixes we have a a center a right and a left we're done sevens we have we have a center a left so this one has to have it on the right left center right that's the only place it can go Okay now what's the ramification of doing that well here is a here is a middle there's a top this one has to be on the bottom so it goes there any ramifications of that no all these sevens are done now okay let's do Eights in these three blocks there's only one eight so we push on to Nines Nines in these three blocks we have only one nine so leave it now we'll go and do vertical blocks on these three going down let's take the ones ones and we got a right we've got a left we've got a center we're set twos we've got one two here and that's all leave it threes now I know some of you are going to say oh I can see how you put another number in don't worry those steps are going to come later in the course okay um Center a right and left they're done four right left Center done fives we have one five here that cancels out this five so this becomes a five okay and that works out you can always check yourself look left center right yes we did it right okay um sixes six we have a six here a six here and a six there and we have a center a left and a right we're doing fine uh eight sevens we're done with the sevens here done eight we have two eights we have two eights we have a center and we have a left this block has a left this block has a center therefore this blocker has to have it on the right so that becomes an eight now what does that mean we've now got this blocked it's only got one number left we can work out what that is very quickly by going one two three oh which is two didn't even get to nine okay now once we've got that two in we look for the ramifications we have a right we have a center and this has got to be on the left so that's the only place it can go now what's the ramification of putting that there well that means it cancels out this two so that two is gone therefore that becomes the big two you see how that works the ramification can just be so powerful you get so many numbers little numbers and big numbers now I look at this block here I notice that there's only one cell left let's count up find out what it is one two three four five six seven eight it's a nine now to check ourselves we have a center a right and a left we've done it right we okay now we're at the stage where we're going to be looking for um blocks and rows and so on that are maybe only got one left one cell left well here's a here's a a column that's only got one left and the number missing is one two three four and there's no five so the five goes in there fantastic okay now we have a block here that only has one left in it let's count up one two three four five six seven eight it has to be a nine we can double check ourselves by going Bottom Middle top now this row here only has one left in it let's count up find out what it is one two three four it's a five that's missing and now we've got this column with only one number left and guess what it's going to be it's got to be eight one two three four five six seven it's eight we've got a nine there so that becomes the eight so we not that no longer is an eight but that block here has only got one cell left it is a two I believe one two yes there's two missing in there now what's the ramification of that anything let's find out look here is something that I had noticed before because this has happened a lot with ramification you've missed it when I put that two in I didn't look this way and look we have a two and a two therefore this becomes a two because it's a top a middle and a bottom now this particular block has only got one left in it one two three four five six seven it's an eight okay eight so we have a left we have a right we have to have a center that becomes an eight now this long row has only got one left one two three four it's a five that's missing we'll put the five in okay now this column here only has one left is that correct oh and this row only has one left and this row is only one left we're getting close to the end okay here we go with uh let me see now uh we'll do this one first one two three four five six seven eight that's got to be an eight and that's a middle bottom top yes we did it right what about this row here we have a one two three four five six seven eight it's got to be a nine and we just if you want to check yourself you go right center left okay this row is this column has only got one left in it one two three four I think it's a five five goes there and therefore this block has only got one left in it or you could do it this column has only got one left and take your pick and I think it's an eight one two three four five six seven eight and voila whoopee we've completed a puzzle what have we done we've done horizontal blocks and then we've done vertical blocks with ramifications and then when we've done all that we look for rows columns and blocks with only one cell left easy now I should give you some heads up on this we're still doing the very easy puzzles don't think that you can now go out and buy a book and they're all the easy ones in the book are going to be easy you know what I've found let me talk a bit about books there's lots of them on the market and there's this there's there's advantages and disadvantages one thing about the books is that I've found sometimes they'll say it is easy and it's not sometimes I'll say it is difficult and it's easy so they're not always that very accurate but generally speaking the larger the number of initial numbers the easier it is but that's only a general comment not always the case also if you're going to go out and buy a book may I suggest listen for me anyway with my bad eyes I buy a book that's got fairly large little cells in it if you buy a book that's got three or four puzzles on one page it becomes too small and gets very smashy with all the little numbers and so on so if you can get a book that's got bigger little cells cells in the puzzle maybe a one one puzzle of page is a great way to go but that's up to you of course there's another thing about books they've got the answers at the back and it's so easy to cheat try and avoid doing that if you can okay now there are going to be some times where you can look at the back of the book to see if you've made a right decision but it's very dangerous because you tend to see other numbers and that's not good so that's it for today's lesson next lesson we go on to some more advanced work and I'm looking forward to seeing you then bye for now

Channel: Sudoku Guy

Views: 5,095

Keywords: Sudoku lessons, sudoku tutorials, sudoku techniques, sudoku tricks, sudoku hints, sudoku for seniors, sudoku for the frustrated, sudoku for the family, Learn, sudoku, sudoku for beginners, sudoku for advanced, sudoku for dummies, how to solve sudoku puzzles, how solve sudoku, brain fittness game, Family sudoku, sudoku for kids

Id: GqpcwY9GA9M

Length: 20min 4sec (1204 seconds)

Published: Sat Dec 31 2022