📕Get my FREE Solving Guide that will help you solve over 80% of all Sudoku puzzles🧩to include NYT Hard👉👉www.buymeacoffee.com/timberlakeB/e/125822 Time Stamps 0:00 Intro 00:31 Empty Rectangle Category 1 01:46 What Is Sudoku Empty Rectangle? 02:08 Empty Rectangle Components 02:43 What Are Empty Rectangle Shapes? 07:29 Sudoku Conjugate Pairs 08:02 Empty Cells 09:33 BONUS Tip 10:30 Empty Rectangle Category 2
This is one of the most hard stuff that I saw here. The bug+1 (and others) were pretty hard but this one is also. I did understand it, the "slice and dice" but I am pretty sure that I would never find this one trying to solve a puzzle. Neitheir do I would find the bug+1... 😅 I solved the fisrt one in 08:02 with your help. The second one I tried to find this strategy but after 3~4min I gave up and just coloured the 37 pairs (done in 4:19). I appreciate your hard work to show us different types of strategies and I will continue to understand it or at least to watch your solve. But some things are just too much 😂 Thank your for another day! 😎
You are welcome, Ana. I appreciate the feedback. I hope you practice looking for more of these. They have popped up in the Sudokupillar puzzles, so I thought I would make an updated tutorial. Many solvers do not use Empty Rectangles much because of how the shapes can vary so much and also that there is usually another strategy that makes the same elimination (skyscraper or finned X-wing).
It took me ages for ER to finally click in my brain, but now I see it as selecting a possible candidate which then forces pointing to make an elimination. Thinking about it like that has helped me with very tricky puzzles where I extend the logic to forcing pairs/ triples and not just pointing. In the first sudoku today I saw the skyscraper first. All the techniques you mentioned are more apparent to my visual brain if I colour all possible candidates for a certain digit. 😊
It takes some pressure off when the video starts with some candidates already filled in, because that means I don't have to consider the video length as a target time. That said, I never found an empty rectangle on the 3's, but I did find a 2-string kite, then later on I found an empty rectangle on the 8's which ultimately solved my puzzle. 40:04 total time, and that's not too bad for a hard puzzle.
I might have solved the first puzzle before, with my work being deleted for space, because it was already marked as liked. I found a finned X-wing and a skyscraper, along with various pairs and triples. The second, with the gargantuan space of given digits, I colored 37 pairs. A cell saw both colors, and I placed an 8. (Formally, they were skyscrapers in 3s and 7s, but their bases were superfluous.) 0:40 I bactracked to this position, but without block 3's 4 placed and with the centermarked grid. My finned X-wing in 3s is a skyscraper in this video's grid because of the 4. The skyscraper is in rows 3 and 6. 1:00 Because I hadn't placed the 4, I didn't have an empty rectangle. The finned X-wing removed two 3s from the top of column 7 and gave me a 169 triple. 11:00 Block 6 has a pointing pair of 8s that eliminates 8 from the rest of column 9. I can see the 37 skyscraper in rows 1 and 4. I colored the 37s.
Good question and feedback. I organize my tutorials to be more search based, so people who found this in search will get what they are looking for quickly. I'll consider taking more time to familiarize the viewer with the position to help set up the need for the target strategy.
@@SmartHobbies I used only basic strategies to get to this point though, so for me it wasn't a huge spoiler. At the very least, none of the cells were coloured.
@ on reflection it is probably my fault. I knew the technique already. A beginner may have found it very useful. Sorry if I was negative - I really do appreciate and enjoy your channel.
@@davidwalters313 It's quite alright. I try to cover these tutorials in under 10 minutes. This one is 13 and I didn't even show what would happen if you placed the digit in the empty cell 😬
📕Get my FREE Solving Guide that will help you solve over 80% of all Sudoku puzzles🧩to include NYT Hard👉👉www.buymeacoffee.com/timberlakeB/e/125822
Time Stamps
0:00 Intro
00:31 Empty Rectangle Category 1
01:46 What Is Sudoku Empty Rectangle?
02:08 Empty Rectangle Components
02:43 What Are Empty Rectangle Shapes?
07:29 Sudoku Conjugate Pairs
08:02 Empty Cells
09:33 BONUS Tip
10:30 Empty Rectangle Category 2
I wasn't very confused before but now I am!
Oh no, Alan! I can help you understand Empty Rectangles better?
This is one of the most hard stuff that I saw here. The bug+1 (and others) were pretty hard but this one is also. I did understand it, the "slice and dice" but I am pretty sure that I would never find this one trying to solve a puzzle. Neitheir do I would find the bug+1... 😅
I solved the fisrt one in 08:02 with your help. The second one I tried to find this strategy but after 3~4min I gave up and just coloured the 37 pairs (done in 4:19).
I appreciate your hard work to show us different types of strategies and I will continue to understand it or at least to watch your solve. But some things are just too much 😂
Thank your for another day! 😎
You are welcome, Ana. I appreciate the feedback. I hope you practice looking for more of these. They have popped up in the Sudokupillar puzzles, so I thought I would make an updated tutorial.
Many solvers do not use Empty Rectangles much because of how the shapes can vary so much and also that there is usually another strategy that makes the same elimination (skyscraper or finned X-wing).
great description! I've been using ERs for a while but never really had a good explanation on how to spot them 🙂
Glad you found it helpful! 😀
It took me ages for ER to finally click in my brain, but now I see it as selecting a possible candidate which then forces pointing to make an elimination. Thinking about it like that has helped me with very tricky puzzles where I extend the logic to forcing pairs/ triples and not just pointing. In the first sudoku today I saw the skyscraper first. All the techniques you mentioned are more apparent to my visual brain if I colour all possible candidates for a certain digit. 😊
Awesome Paula. Glad it’s starting to click. Thank you so much for sharing.
Interesting
It takes some pressure off when the video starts with some candidates already filled in, because that means I don't have to consider the video length as a target time. That said, I never found an empty rectangle on the 3's, but I did find a 2-string kite, then later on I found an empty rectangle on the 8's which ultimately solved my puzzle. 40:04 total time, and that's not too bad for a hard puzzle.
I might have solved the first puzzle before, with my work being deleted for space, because it was already marked as liked. I found a finned X-wing and a skyscraper, along with various pairs and triples. The second, with the gargantuan space of given digits, I colored 37 pairs. A cell saw both colors, and I placed an 8. (Formally, they were skyscrapers in 3s and 7s, but their bases were superfluous.)
0:40 I bactracked to this position, but without block 3's 4 placed and with the centermarked grid. My finned X-wing in 3s is a skyscraper in this video's grid because of the 4. The skyscraper is in rows 3 and 6.
1:00 Because I hadn't placed the 4, I didn't have an empty rectangle. The finned X-wing removed two 3s from the top of column 7 and gave me a 169 triple.
11:00 Block 6 has a pointing pair of 8s that eliminates 8 from the rest of column 9. I can see the 37 skyscraper in rows 1 and 4. I colored the 37s.
Nice job John, finding the skyscrapers and finned x-wings. I tend to see those first, as well.
Cross shape as well....
The second one stumped me. Maybe it'll take time to understand it.
They get easier with practice. I hope you can consider ER's more when looking for single candidate strategies.
I actually solved it easier by using the “37” pairs and solved for the 8 in box 2.
Cool. Thanks for sharing. 😎
Why are you beginning with a half full grid? You should have waited 10 seconds with that, allowing us to explore some of it on our own terms first.
Good question and feedback. I organize my tutorials to be more search based, so people who found this in search will get what they are looking for quickly. I'll consider taking more time to familiarize the viewer with the position to help set up the need for the target strategy.
@@SmartHobbies I used only basic strategies to get to this point though, so for me it wasn't a huge spoiler. At the very least, none of the cells were coloured.
It’s easy to criticise but a rather cumbersome explanation for what is a very simple concept. Sorry to be a bit negative.
Thank you for the feedback David. I'll use that to simplify my future tutorials.
@ on reflection it is probably my fault. I knew the technique already. A beginner may have found it very useful. Sorry if I was negative - I really do appreciate and enjoy your channel.
@@davidwalters313 It's quite alright. I try to cover these tutorials in under 10 minutes. This one is 13 and I didn't even show what would happen if you placed the digit in the empty cell 😬