Mini sudoku? | 3x3 by Phurba

Added: 2026-05-17

[00:00:10]Hello, good day and welcome. I'm Dumatab and today I'm going to solve 3x3 by Fer.

[00:00:16]Um, if you would like to try solving this puzzle for yourself, it'll be the first link in the description. Before I get to the rules, I am currently on a push to get to 1,000 subscribers.

[00:00:27]Um, so if you've not yet subscribed, I'd really appreciate it if you would. Um, that will help the algorithm uh, let people know that um, this is content that people enjoy. So would really appreciate your help with that. Doesn't cost you anything and it helps me out.

[00:00:46]All right, let's have a look at the rules. Normal Stoker rules apply. So we are going to place the digits one to nine once each and every row, every column and every box.

[00:00:57]uh digits in a cage cannot repeat and must sum to the small number in the top left corner. So those three digits sum to nine as do those three. And crop key pairs digits separated by a white dot are consecutive. So if this were a two, this could be a one or a three. Uh not all dots are necessarily given. So, by the rule, if this is a two, it's perfectly fine by for that to be a one or a three, even though there's no drop between them.

[00:01:28]I'm going to restart the puzzle to reset the timer, and let's begin.

[00:01:33]Okay, we have a distinct pattern of nines, nine cages.

[00:01:40]Um, and the question is well I can see that so there there are three different kinds of nine cage with three cells. There's 126 135 and 234.

[00:01:58]And I can see that these two have to be different because if they were the same, say one two six, then I would have four digits um or four cells that have to be made up of three different digits which would necessitate a repeat and that's not going to work.

[00:02:17]So does this one have to be different from both of the other two?

[00:02:27]And the answer to that question is yes.

[00:02:32]Right. So each nine cage has two digits from 1 2 and three.

[00:02:40]Um and then it has one digit from four five and six and no digits from 7 8 and 9.

[00:02:49]So um the reason we can easily see that it has two digits from 1 2 and three is let us suppose that it only had one digit from 1 2 and three. If I make that one digit as low as possible that be a 1 and then put in the next two lowest digits in that are not two and three that would be four and five but 1 + 4 + 5 is 10. So this has two digits from 1 2 and 3 in.

[00:03:15]And this has two digits from one, two, and three in. And this has two digits from one, two, and three in.

[00:03:22]And what that means is if these two cages were the same, which um absent anything else in the grid, they could be that would use the same two digits from 1, two, and three in.

[00:03:38]Um, and then where would this get its two digits, two low digits from? There's only one left available in rows two and three at that point.

[00:03:51]So, these three have to be different.

[00:03:54]Um, and in the columns in the stacks, the um, uh, the nine cages have to be different as well. So, these nine cages are also going to form like a 3x3 sedoku. I guess that's where the title comes from.

[00:04:10]But how does that help?

[00:04:14]How does that get me any digits in the grid? Because there's not an awful lot apart from those nines. There's just four white dots.

[00:04:25]Um, okay. That's really nice.

[00:04:42]So if I have um two low digits there and two low digits there and two low digits there, how many of each of 1, two, and three have I used up in the those two rows?

[00:05:00]And I've used two ones, two twos, and two threes.

[00:05:05]So that means that none of those digits or although none of those cells can be 1, two, or three. I'm just going to highlight those for a moment. Those cannot be 1, two, or three.

[00:05:16]But I can say the exact same thing for rows five and six.

[00:05:22]Those can't be 1, two, and three. And I can say the exact same thing for rows eight and nine.

[00:05:31]But columns two and three, I can say the same thing that I've got uh 1, two, and three twice in the nine cages. So all of these cells are also not 1, two, and three.

[00:05:48]And I can't have 1, two, and three in the nine cage because that only sums to six. So where does my third digit from 1, two, and three go? And that's in these top left cells.

[00:06:02]That's really really nice. That's very clever.

[00:06:07]So do my Yeah, let's remove that coloring. So those are from 1, two, and three. Now this if this were from 1, two, or three, it would make a fourth one, two, or three in the row. So that cannot be. So that has to be a four, which makes that a three. Uh, and this dot does the same. That's a four. So that's a three.

[00:06:29]that eliminates three from all of these cells and means that that's a three.

[00:06:41]Okay.

[00:06:46]So, uh now I don't have a three in this nine cage. That has to be 126.

[00:06:54]And that has to be 126.

[00:06:57]And that has to be 1, two, six.

[00:07:02]7, 8, and nine don't go in nine cages at all. So, looks like I've got a 789 triple there and a 789 triple there.

[00:07:16]All right.

[00:07:31]Now what?

[00:07:49]So okay, one of those two is a six. So all the sixes that are in nine cages are approximately in the grid. So those can't be from those can't have a six in and those can't have a six. That can't have a six in because these are not 126 cages. So one of those two is a six. So that's not a six.

[00:08:20]I guess where does six go in this column asking the same kind of question that must be a six and those two are not.

[00:08:35]So these by the column are one, two, three and five.

[00:08:44]And these two are three, four, and five.

[00:08:47]And one of these two is a four because one of these cages is a 2, three, four cage.

[00:09:08]Um, so one of these is a 135. five cage and one of them is a 2 3 4 cage.

[00:09:43]But where does the five go in this column? I don't know exactly, but it goes in one of these four cells, right?

[00:09:53]And if if it's in this cage and if it's one of these two, then that's not a five because um the five is in one of these two.

[00:10:09]But if it's not in one of these two, then it must be in one of these two. And this is not a 135 gauge because this would be the 135 gauge. So in either case, that's not a five and that's not a five.

[00:10:26]So that gives me a three four pair.

[00:11:06]So, so what?

[00:11:18]Okay.

[00:11:21]Yes. If this is a four, where does four go in this column?

[00:11:28]If that's a four, it's not in one of those two. It's clearly not one of those. So, it's in one of these two. But that's a problem because if this is a four, then this is a 234 cage. This is a 1 135 cage. And what's the four that's in one of these two going to go next to?

[00:11:44]It can't go next to three or five.

[00:11:47]So, that can't have a four on it. So, that is not a four. And this is a four.

[00:11:52]And if that's a four, this is a 2 3 4 cage. So that's two or three. This is now a 1 53 cage.

[00:12:03]Um so that's a three there.

[00:12:07]This means that this five that gives me a two there, a one there, a two, a one, a two, and a one. And I guess in these top left corners, we've just done another 3x3 sudoku.

[00:12:28]Okay.

[00:12:33]So, if this is a 2349 cage and that's a 126, this must be a 135, which makes this 234.

[00:12:47]This is 135.

[00:12:50]And this is 2 3 4. Okay, those aren't three. So that's a three there. That means that that is not a two.

[00:13:07]That four means that those are not four and that is that two. Three is looking down. So that's a one or a five.

[00:13:17]That's not a two. So that's a two.

[00:13:30]Six is looking up. That's a five.

[00:13:46]Okay. What next?

[00:13:56]that white dot.

[00:14:00]Uh 6 7 8 or nine or five. That could be 56.

[00:14:12]Yeah, that cell is 6, seven, eight or nine. But ah this four is not in there. And this two four is looking at that cell. So that's a four.

[00:14:32]This is a four.

[00:14:41]So now four is in one of those two.

[00:14:45]Can four be on the dot? No, it can't because uh it can't be next to a three here because we have a three here and we have a five here. So that can't be four. So that's a four.

[00:15:09]That can't be a five because of that.

[00:15:12]That can't be a five because that can't be four or six. So that's a five.

[00:15:19]That places a five there.

[00:15:23]That gives me a five in one of those two, which means in this row, five must be here.

[00:15:34]Five is in one of those two. And then five is in one of those two.

[00:15:43]So these are from 7, 8, and nine.

[00:15:48]Um, and I need an even digit on a dot.

[00:15:51]So that can't be an eight cuz one of those two is I have a 7 8 9 in the row. So that has to be six.

[00:16:00]That can't be four. So that is that makes that 7 8 or 9 which means that I've got a 7 8 9 in the row.

[00:16:15]This is not 1 2 3 four or five from the box and it's not 7 8 9 from the row. So that's a six. This can't be five. So it's seven.

[00:16:28]That's now 8 9. That six means that that is not a six. That's a one or a two.

[00:16:40]That's not seven.

[00:16:47]This is a very fun puzzle.

[00:17:04]To complete this column, I need 5, eight, and nine.

[00:17:08]Uh, that's eight or nine. Five is in one of those. Those are from 5 8 9.

[00:17:17]So this has to be 78.

[00:17:38]Six is in one of Yes. Six is not there. So that's a six.

[00:17:46]So those are 7, eight or nine.

[00:17:50]But one of those two is a seven from the row. So that's not a seven. That gives me an 8 n pair. Meaning that's a seven.

[00:17:59]So that is not seven.

[00:18:04]So seven's in one of those two. That's not a seven.

[00:18:21]Six is in one of those two. So six in this column must be in one of those two.

[00:18:35]So these must be from 7, 8, and 9.

[00:18:39]And that one can't be an eight.

[00:18:42]Is that right?

[00:18:46]Not 1 2 3 4 or five or six. Yes. So those are indeed from 7 8 and 9. That is not an eight because we know that one of those two is an eight. But that gives me a 7 8 9 triple in the row. So that's a five.

[00:19:03]So that is not five.

[00:19:07]gives me a one, two, three triple in the row.

[00:19:18]Well, this three has been looking up there for ages.

[00:19:23]That's a one or a five.

[00:19:30]This this that four is looking down. That's a two.

[00:19:51]That's a four.

[00:19:53]So that's a one. That's a six. That's a two.

[00:19:59]That's a one. That's a three. That's a five.

[00:20:04]That resolves the two and three there.

[00:20:07]And the two and the one there.

[00:20:11]That one is looking across making that three and that one. So that's two and that's three.

[00:20:25]That five is looking down. So that's a five.

[00:20:32]That is not six by the column. That's not six by the column. So that is a six.

[00:20:39]Making that 7 8 or 9.

[00:20:43]These are from 7 8 and 9.

[00:20:47]This is 7 8 or 9.

[00:20:51]Uh in fact that six is looking up. That is 78 or 9 and that is a six.

[00:21:00]So this is seven, eight or nine.

[00:21:39]Okay.

[00:21:41]Now what?

[00:22:00]H these are from 678 9.

[00:22:07]Let's remove the corner mark.

[00:22:11]These are from 578 9.

[00:22:15]And again remove the corner mark.

[00:22:42]Where is the pressure?

[00:23:06]Where is the pressure?

[00:23:10]Should I color my sevens, eights, and nines?

[00:23:17]Or even just my eights and nines? Maybe that.

[00:23:22]So, let's color that one green, which makes that one purple, which makes that one green, which makes that one purple, which makes that one dream.

[00:23:58]That is green.

[00:24:07]So, one of those two is purple.

[00:24:18]So, that is not purple. So, that must be green.

[00:24:22]And now this must be a seven because it sees green in the box and purple in the column. So, that's a seven.

[00:24:32]And so now that is purple but that makes that nine which makes that eight which makes green eight.

[00:24:49]Uh this must be a seven because of the nine. So that's nine and uh purple.

[00:24:57]Um, these are all nines. I think my coloring has done what it needed to do.

[00:25:08]That is a 79 pair there.

[00:25:11]That is a seven there.

[00:25:14]So that's an 89 pair. This is now a 67 pair.

[00:25:22]That seven and nine is looking down.

[00:25:24]That's an eight. So that's nine.

[00:25:27]That is seven.

[00:25:29]That makes this six and this seven. That makes that one. And that's six. That's five. And that's one.

[00:25:42]That's a five.

[00:25:44]That is not five or seven.

[00:25:49]That eight is looking down. That's a nine. That's an eight. That's a nine.

[00:25:55]That nine is now looking up. That's a seven. That's a nine.

[00:26:03]That's an eight. And that is a seven.

[00:26:09]That is a phenomenal puzzle. I really, really enjoyed that. Um, so elements I liked were it not being completely obvious at first glance that even though it was a hint that in the title, but there's a good and there was a good uh feeling that these were probably three different kinds of nine cage but proving that was nice.

[00:26:38]Um and then the consequence of that forming the uh one, two, three triples in these corners and then the white dots to force the three. And then um for not being able to be on this dot in order to uh because if it were this would be a 135 gauge and then um three and five couldn't be next to the four.

[00:27:14]Uh yeah. and then um using coloring to figure out that this saw both of the eight and nines that we had.

[00:27:31]Really, really nice puzzle. Thoroughly enjoyed it. Um and not too difficult if you have the right insights.

[00:27:38]Well, I enjoyed this solve. Um I hope you did, too. If you did, please hit the like button. You can subscribe to see some more. And I would love to hear your comments. I'm looking forward to next time. Be safe with you.