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 Timestamps 0:00 Intro 00:32 It’s Solving Time 00:36 XY-Wing Tip #1 03:12 XY-Wing Tip #2 05:26 BONUS Tip 05:52 What To Do When Stuck 06:40 XY-Wing Tip #3 08:50 XY-Wing Tip #4 10:39 XY-Wing Tip #5 13:34 Seeing Effect Of XY-Wings
I found my first Y-wing while centermarking five-digit houses, after cornermarking: 129 in blocks 7 and 9. As usual, when I have nothing else to do, I centermark the grid. Afterwards, I check through each digit. (All 6s were placed by then.) I placed a lone 5 in column 6, but what got me going again was noticing that I had 4s marked that could see a given 4. Fixing that gave me a 18-pair in column 3, which became a two-option Y-wing with two corner cells -- my second and last Y-wing. The rest was cleaning up, with the help of three triples. 0:40 Tip #1: My first Y-wing was a counterexample -- I found it fairly early. I was also reminded of a puzzle several months ago, where I also found an early Y-wing. Watching the video, I thought it was superfluous until right at the end, when I discovered that it did the dirty work of some kind of W-wing that I didn't understand. 9:10 Once I took care of the 4s, that green cell became a 18-cell, giving the 18-pair. (The first Y-wing had already removed the 9.) 10:10 That one was the one I found early on. It has occurred to me that perhaps a "V-wing" might be a better name. 12:20 That was the Y-wing I found considerably later. I decided to apply the 18-pair first. Not that it made a difference.
Good puzzle, SULPHUR always gives some tough and happy finishing. Filled no's in all cells, got the XY wings, second one 18 is down, and it's, top or down gives same result. Enjoyed, saw vedio nice explanation. Thanks for the puzzle.
Fun puzzle. Crux is a double X-Y wing facing R7C7. R1C1 as pivot and R3C3, R9C1 as pincers knock out the 1. R9C9 as pivot, R7C7, R1C9 as pincers knock out the 9, leaving only an 8 as a possibility there. After that, it's all pretty routine, nothing advanced needed. Now to watch the explanation.
That is a great question, Pokey. They work on both. Most of my viewers prefer hand-crafted due to the intended solve path usually being more fun to discover.
Well, I found an XY-Wing, but I still needed a quick bit of virtual chaining to continue (83 = row 8 column 3): 83, 54, 56, 81, 78, 19, 35, 98, 68, 57, 73 (XY-Wing, boxes 1 and 7, plus virtual 9 tried in R9C5, quickly leading to a contradiction), 33, 36, 12, 28, 65, 62, 21, 38, 32, 51, 42, 91, 11, 53, 24, 63, 52, 23, 89, 26, 64, 75, 66, 84, 44, 74, 99, 27, 29, 47, 89, 77, 92, 27, 95, 16, 15, 86, 85, 18, 49, 59, 45, 55, 48. Ah, I missed the second XY-Wing. that would have led to the same continuation. A clever puzzle.
Glad you were able to solve it, Julian. Sulphur spent months on the puzzles for our latest puzzle pack, and they are all as clever as this. Would you like to become a Smartie Party member to check the rest of them out?
I agree and I’ll consider your feedback in making future videos. In the meantime, you can learn all about XY-Wings in this tutorial: th-cam.com/video/pE3Z_CvFFME/w-d-xo.htmlsi=ZzfskkeJjivvDbFh
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
Timestamps
0:00 Intro
00:32 It’s Solving Time
00:36 XY-Wing Tip #1
03:12 XY-Wing Tip #2
05:26 BONUS Tip
05:52 What To Do When Stuck
06:40 XY-Wing Tip #3
08:50 XY-Wing Tip #4
10:39 XY-Wing Tip #5
13:34 Seeing Effect Of XY-Wings
I found my first Y-wing while centermarking five-digit houses, after cornermarking: 129 in blocks 7 and 9. As usual, when I have nothing else to do, I centermark the grid. Afterwards, I check through each digit. (All 6s were placed by then.) I placed a lone 5 in column 6, but what got me going again was noticing that I had 4s marked that could see a given 4. Fixing that gave me a 18-pair in column 3, which became a two-option Y-wing with two corner cells -- my second and last Y-wing. The rest was cleaning up, with the help of three triples.
0:40 Tip #1: My first Y-wing was a counterexample -- I found it fairly early. I was also reminded of a puzzle several months ago, where I also found an early Y-wing. Watching the video, I thought it was superfluous until right at the end, when I discovered that it did the dirty work of some kind of W-wing that I didn't understand.
9:10 Once I took care of the 4s, that green cell became a 18-cell, giving the 18-pair. (The first Y-wing had already removed the 9.)
10:10 That one was the one I found early on. It has occurred to me that perhaps a "V-wing" might be a better name.
12:20 That was the Y-wing I found considerably later. I decided to apply the 18-pair first. Not that it made a difference.
Nice job John. I’m glad you found XY-Wing early. Like you mentioned, that is not too common.
Very nice one. Learning new things with every video.
Glad to hear that. Thank you so much for watching!
Are there any other strategies you want to see?
Good puzzle, SULPHUR always gives some tough and happy finishing. Filled no's in all cells, got the XY wings, second one 18 is down, and it's, top or down gives same result.
Enjoyed, saw vedio nice explanation.
Thanks for the puzzle.
I am glad you enjoyed the puzzle and the video. Thank you for watching.
11:42 with your help. It wasn't hard but I couldn't find the xy-wings one more time 😅 thank you! ☺
Any time. 👍🏻
I first completed it using mostly SET theory but will redo with the xy wings instead. I am practising both methods.
Nice job, Vanessa. I love that you applied SET to this 🧩.
Fun puzzle. Crux is a double X-Y wing facing R7C7.
R1C1 as pivot and R3C3, R9C1 as pincers knock out the 1.
R9C9 as pivot, R7C7, R1C9 as pincers knock out the 9, leaving only an 8 as a possibility there.
After that, it's all pretty routine, nothing advanced needed. Now to watch the explanation.
You nailed it. Thank you for sharing.
Do these techniques work on computer generated puzzles or only hand-crafted Sudokus?
That is a great question, Pokey. They work on both. Most of my viewers prefer hand-crafted due to the intended solve path usually being more fun to discover.
Well, I found an XY-Wing, but I still needed a quick bit of virtual chaining to continue (83 = row 8 column 3):
83, 54, 56, 81, 78,
19, 35, 98, 68, 57,
73 (XY-Wing, boxes 1 and 7, plus virtual 9 tried in R9C5, quickly leading to a contradiction),
33, 36, 12, 28, 65,
62, 21, 38, 32, 51,
42, 91, 11, 53, 24,
63, 52, 23, 89, 26,
64, 75, 66, 84, 44,
74, 99, 27, 29, 47,
89, 77, 92, 27, 95,
16, 15, 86, 85, 18,
49, 59, 45, 55, 48.
Ah, I missed the second XY-Wing. that would have led to the same continuation. A clever puzzle.
Glad you were able to solve it, Julian. Sulphur spent months on the puzzles for our latest puzzle pack, and they are all as clever as this. Would you like to become a Smartie Party member to check the rest of them out?
Pair of 18 in column 3 (11:49)
Thank you for pointing that out Roger. That does make the solve go a little easier if you spot that pair.
It would be helpful to explain what an XY-wing is before asking us to find one..
I agree and I’ll consider your feedback in making future videos.
In the meantime, you can learn all about XY-Wings in this tutorial: th-cam.com/video/pE3Z_CvFFME/w-d-xo.htmlsi=ZzfskkeJjivvDbFh