Join the Smartie Party now to get EXCLUSIVE reward puzzle packs, ad free content, discord access, and so much more 👉www.buymeacoffee.com/timberlakeB/membership Time Stamp: 00:43 Intro 1:42 Hard puzzle walkthrough 5:40 W-Wing components 13:45 W-Wing Example 1 16:38 W-Wing Example 2 19:28 W-Wing Example 3

I used cells R3C2 R3C3 together with R9C2 R9C3 to get R9C2 to be 4 by simple uniqueness

@SmartHobbies

2 жыл бұрын

Nice job. I love hearing other solvers make their way through a puzzle and what strategies they find.

I'm still kinda getting lost among all the different techniques, what's the one you pulled at 9:42 and then later at 10:24?

@SmartHobbies

2 жыл бұрын

Great question. I applied a strategy called a unique rectangle (type 7). We know the puzzle has 1 unique solution. In the first example, the 5’s were limited in those 2 rows to exactly 2 columns in the same 2 blocks. The 6’s were not limited. Each of the 4 cells contained both 5 and 6, and at least 1 of the cells contained just those 2 candidates. You look at cell that is diagonally across from the 5/6 bivalue cell and you can eliminate the candidate that is not limited (which is the 6). The reason is if that cell was a 6, then that would put 5’s in adjacent cells and 6 in the bivalue cell. If we solved the entire puzzle, then you could look at the finished grid and be able to swap the positions of the 5’s and 6’s I. Those 4 cells. That would be impossible since puzzle only has 1 unique solution. I talk about this more clearly in some of my other videos where I solve unique rectangles. Does that make sense?

@marnak24

Жыл бұрын

Hi Timberlake, in what video do you explain the UR more? Thanks!!

1:20 I'm beginning the puzzle now. (I entered it into Sudoku Exchange.) I'm sure I'll have more to comment as I progress (or not) through the puzzle. I got stuck at various points, but managed to find something to progress the puzzle. A couple Y-wings eliminated a couple of 6s and 7s from box 9. A 23 in R8C8 either set up a deadly pattern or broke it. A couple short chains showed that the wrong choice led to a crash. A 69 in R7C5 had this property: the wrong choice forced a 9 in another 69 cell along one path, but forced a 6 in the same cell along a different path. The right choice finally persuaded the puzzle to yield. So back to the video. 5:20 Regarding Rashmika Abajian's comment, I placed the 8 when I noticed that position filling out box 1. I don't know what a hammer pattern is, unless it's the 8s or the potential deadly pattern in boxes 2 and 3. 8:00 I went back to the last chain and decision point to see how your W-wing would play out. (I refuse to return to before the two Y-wings and the deadly pattern prevention.) My grid is simpler: column 7 has all digits placed except for a 69 pair in rows 5 and 9. Row 8 has all digits but a 39 pair in columns 5 and 9. So I will see if a W-wing is possible here. 9:10 At this point, you can place a 4, 8, and 5 in column 7. You'll probably see that in short order. 9:50 Screamer Alert refers to the digits in my previous comment, except that I didn't have that 69 pair yet. After placing the 4, Box 3 has a pair of 8s pointing down, placing the 8 in box 9. Then the 5 is alone. That gave me the 69 pair. (I didn't see the potential deadly pattern in boxes 7 and 9.) 10:30 The highlighted cells are the potential deadly pattern that caught my attention for a while. (R8C8 had 23. I didn't actually base my choice of 2 on avoiding the deadly pattern. Rather, I saw that 3 led to a crash.) 11:10 That Y-wing was the first advanced position I found -- after placing the digits in column 7. 12:50 Right after that Y-wing, a second Y-wing is visible: 6, 7, and 9 in boxes 7 and 9. 13:50 Ahah, we're back at the 69s, and the grid resembles my position more than before. 15:10 Here's what I finally noticed there: if R7C5 were a 9, then 3 must be immediately below. Far to the right is a 9. Below is a 6. The 69 in R9C7 can't be either. The 6 in R7C5 finally persuaded the puzzle to yield. Example 2: 16:50 First thing I noticed is that both 53 cells must be the same. The second thing is that if they're 5, we get a deadly pattern in columns 1 & 9. I want to avoid using that fact. 18:10 I see the chain of logic ruling out the 2 in R8C5. I'm not sure that I could find it myself. Example 3: 19:50 I can see that the two orange cells must be opposite. I doubt that I could find it myself.

@SmartHobbies

Жыл бұрын

You are getting better at this and will start seeing more of these strategies sooner. Thanks for sharing your commentary and insights.

9:53 I absolutely loved this part of the video where you put that text up with the alert. I paused the video and went searching to understand that and how it worked. I had to think about it for a bit, too. I understand pairs, but it took me a bit to immediately see the 9 it removed, and then looked again at your alert and you directly said which cell, too. That was a fun bit of hide and seek mixed in with the rest of an informative video. Thanks for that!

@Corwin256

3 жыл бұрын

So I just finished the video and I gotta say I appreciated the extra examples. I tried following the second example and I just really didn't understand that even after replaying, but when you got to the third and walked us through again, it started to really click with me. I've seen these sorts of W-wings before and sensed they must be important, but didn't know they had a name and certainly didn't know what the importance was. I'm excited to go back to some Sudoku and look to spot these.

@SmartHobbies

3 жыл бұрын

You are welcome and thank you for the comment. Im glad it was helpful. So many times I’ve watched CTC and I’ll fixate on a cell that I can solve that they don’t see yet. When I go back to edit, I’ll see so missed opportunities that I didn’t catch when I solved in real time. I decided to call them screamer cells.

@SmartHobbies

3 жыл бұрын

@@Corwin256 I’m glad this was helpful to you. Before this video, I had a hard time spotting W-wings myself. Putting in practice and research helped me see them easier, so I kept at it until I could explain it to others. I get joy when I discover a new strategy that helps me progress through a puzzle at a point where I used to get stuck. I hope this helps you do the same.

I went back in time for this one. It took me1:40, not counting the time to watch the video and try to figure out the logic. So added up, about 2 1/4 hours. Been a long time since I spent this much time on a puzzle. The unique rectangle on the 28's (blocks 2&3) really threw me because it was not the regular setup for a unique rectangle. I had to go over it many times with coloring to see why it was okay to eliminate the 2's from block 3 column 8.

@SmartHobbies

3 ай бұрын

I am glad you stuck with it Brad. Excited to see one of my regular viewers looking at some of the earlier videos 😎

What a brilliant tutorial, most just jump in and say, 'lets look at this candidate' and then show the logic but here you show how you arrived at the candidate. refreshing although I will practice with Hodoku to cement it, thanks, I need similar for various types of chains now 😀

@SmartHobbies

7 ай бұрын

Thank you so much for watching and for the kind words. I try to do exactly what you expressed in your comments. I wish you the best on your Sudoku journey, and I hope to hear from you again soon.

Who are the other two channels that you mentioned?

@SmartHobbies

2 жыл бұрын

Thank so much for watching. The first channel I mentioned was DxSudoku. The other is SudokuSwami. Both have great Sudoku videos about W-Wings and other advanced Sudoku strategies.

Sir, I enjoyed the puzzle. Attained more clarity when I went through the comments of readers and your clear-cut explanation. Superb.

@SmartHobbies

7 ай бұрын

Thank you so much for the kind words and for watching. I appreciate it!

What an excellent explanation, I am really understanding a lot thanks to your explanations

@SmartHobbies

2 жыл бұрын

Thank you so much! I love to hear that you understanding sudoku better and I wish you happy solving.

Hey! I noticed at 5:07 when you're looking at 8s, you could have placed the 8 in c1r2. It's the only 8 possible in the row, but what caught my attention first was the hammer pattern in box 2 and 3.

@SmartHobbies

2 жыл бұрын

Nice job pointing that out. That helps me understand my own solving blind spots. Thank you so much for watching.

@eisenbam2012

2 жыл бұрын

@@SmartHobbies it was a joy to watch! It's fun to solve along with you and learn :)

Great video. Just wonder what app is this so I can tried on my PC

@SmartHobbies

2 жыл бұрын

Thank you so much for watching and for the kind words. I used Hodoku for that video, which is a free software app. It has a great puzzle generator to help you practice all kinds of strategies.

This seems to be a wonderful app to learn the techniques. Is there a similar app for Mac?

@SmartHobbies

2 жыл бұрын

Thank you so much for watching. I use Hodoku which is a free web-based app. They have a mac download as well. Hope that helps.

This puzzle would be a good example of using 3d medussa...I would use the method myself but I only do puzzles in books and they never give enough room to work! :(

@SmartHobbies

Жыл бұрын

Ok. I’ll look into it. Should be fun.

I'm not clear on how you eliminated the 2s in block 3 column 8.

@SmartHobbies

Жыл бұрын

Great question, Frank. I identified a Unique Rectangle (Type 4) that allowed me to eliminate the 2's Block 3, column 8. It works under the assumption that the puzzle has a unique solution. Since the 8's are limited to exactly 2 rows, 2 columns, and 2 blocks and shares those cells with the 2s, then we know if we put a 2 in either of the block 3 cells, it would force the 2 and 8s in the rest of those 4 cells. In theory, if we solved the whole puzzle and one of those cells had a 2 and the other an 8, then the puzzle could have another solution where the positions of the 2 and 8 in those 2 columns are switched. Since we know the puzzle only has 1 unique solution, we can eliminate those candidates. I recommend you check out my unique rectangle tutorial here where I go through all 7 situations where this occur: kzread.info/dash/bejne/iWh3z8Owcsublbg.html Hope that helps.

@frankgiacon3983

Жыл бұрын

@@SmartHobbies Thanks, just watched your unique rectangles video. All very logical and legit but still feels like cheating to me. You do mention intention. I did solve that puzzle without using that strategy because I didn't understand it. Don't ask me how.

@SmartHobbies

Жыл бұрын

@@frankgiacon3983 Most unique rectangle situations have another way to solve using different logic.

Timberlake, what is the diff between W-wing and Skyscapper? Is it the same technique?

@SmartHobbies

Жыл бұрын

Not quite. Skyscraper involves all one candidate. The one candidate will appear exactly twice in 2 rows or columns and will share 1 of the opposite (row or column) with each other. W-Wing has the same bivalue cells as beginning and end cells and they are connected by a conjugate pair of one of the two candidates in the bivalue cells (for example, if 45 are in the beginning and end cells, then they need to be connected by a conjugate pair of either 4 or 5). I go into more detail in my difference between w-wing and wxyz-zing tutorial. Does that help?

@alexanderstelmakh8906

Жыл бұрын

@@SmartHobbies tnx, but isn’t it just 2 skyscappers, on on 4 and one on 5?

@SmartHobbies

Жыл бұрын

@@alexanderstelmakh8906 It would look the same in one of the 4 W-Wing variations. But the ones where the the conjugate pairs are between the bivalue cells (the “beyond diabolical…” analysis video has one of these), and when one of the conjugate pairs is in the same block as one the bivalue cells would be different from a skyscraper.

@alexanderstelmakh8906

Жыл бұрын

@@SmartHobbies Tnx a lot! Will check the “diabolical” video.

What app are you using?

@SmartHobbies

2 жыл бұрын

I used Hodoku for this video. Thank you so much for watching.

@dennissousa8226

2 жыл бұрын

@@SmartHobbies only works on PC no android app. The one I use enjoy sudoku is a great app but doesn't have the feature that highlights all the by value cells.

@SmartHobbies

2 жыл бұрын

@@dennissousa8226 I haven’t tried that one. Thank you for letting me know. Hodoku has some great features like a training mode along with all the coloring.

Ich bin nicht glücklich mit dem Namen W-Wings, sie scheinen der Quantenverschränkung zu ähneln, aber lassen wir das den Physikern. Ein angemessener Name wäre Timberlake- Paare oder wenigstens T-Paare.

@SmartHobbies

Жыл бұрын

I love your name for these. Thank you so much for suggesting it. 😀