Empty Rectangle and the LOGIC Behind It

Рет қаралды 26,853

9 ай бұрын

Lesson #17: The Empty Rectangle appears more often than you would think, you just have to know how to look for it. In this video I explain the pattern first, and then show you two real Sudoku puzzles in progress to demonstrate this very useful pattern. I hope you enjoy this tutorial, and, I hope you Learn Something!

Пікірлер: 23

@thejose965 3 ай бұрын

Great lucid explanation... Thanks a ton from Kuwait 🙏

@jenschafer269 8 күн бұрын

This helped me finish the NYT hard puzzle today!

@tomdalziel4607 4 ай бұрын

Thank you for taking the time to explain every step of the process so clearly!!! 😀💟

@charlottewebb3364 5 ай бұрын

I Like your nuts and bolts approach in describing these patterns. You should write a book or make one available for download. It would be well worth the purchase.

@jaimeriquelme6727 6 күн бұрын

Smart girl, thanks for your lesson and your time.

@thomaswilke6312 3 ай бұрын

Very clear and concise explanation. Thank you very much

@wwfgumby 6 ай бұрын

Well described, thanks.

@eugenetswong Ай бұрын

Thanks for this! I didn't use it specifically, but it didn't help. Using a conjugate pair like that makes a big difference.

@duffelesser6210 4 ай бұрын

Amazing! thx from germany!

@yolotaylor993 4 ай бұрын

Very clear, thanks

@wegtennis8740 2 күн бұрын

In your last example, isn't there also an empty rectangle related to the 2's in block 9 that would lead to the elimination of 2 in the lower left corner of block 3 (cell 7)? This would then leave 2's in cells 3 and 9 of block 3, resulting in the same final result of eliminating the 2 in cell 6 of block 9? Would one of you smart folks let me know if I'm understanding the process? Thx

@kaskazimnoch9583 2 ай бұрын

You're the best.

@dunnetahl 6 ай бұрын

Really aweome technique. Just used this with multiple numbers to solve a puzzle I had completed all pairs, triplets, then x wing, y wing, swordfish and slanted skyscrapper were all nil, but I had several key empty rectangles that helped me solve the puzzle. This technique is really easy to spot, understand and apply.

@VistasdelMar2008 2 ай бұрын

In your last real world example, does the logic of eliminating the 2 in the 9th column also imply that the 2 in the same row immediately adjacent in column 7 also get eliminated ?

@aspartaami Ай бұрын

No, because it doesn't see the empty rectangle. Only the one seeing the empty rectangle can be eliminated.

@seemashrivastava1661 8 ай бұрын

Is it necessary that the conjugate pair should be in different blocks,Or they can be in same block?

@macfid 6 ай бұрын

Go to 6:40

@billgillaspey9036 8 ай бұрын

I'm really enjoying your Sudoku videos; thank you for them. Question: who determines--and/or HOW do they determine--whether a puzzle is hard or "easy". I'm assuming that the number of slots out of 81 slots which are blank is one factor. But what else: is it part of the algorithm that generates these puzzles? Is there Sudoku "checker" that rates them (like a restaurant reviewer...) . Always wondered....

@kyldare 6 ай бұрын

I'm having a hard time figuring out which number is considered to be in the same row/column. As an example, why couldnt the 2 on h9 be considered the one on the same column then removing the 2 from C6 instead? For the example on 12:53

@Jake_Cotumaccio 3 ай бұрын

If you start by choosing the 2 on H9, you’d need there to be only one other 2 in row 9. This is what she means by “conjugate pair”- there’s only two instances of a given digit (2 in this case) in a particular row or column. However, because there are more than two 2s in row H, you can’t use the 2 on H9 as the basis for the empty rectangle trick. You can use the 2 in column 6 because there are only two 2s in that column, meaning it is part of a conjugate pair. Hope that helps!

@TomJones-tx7pb 13 күн бұрын

If you have a valid puzzle, you can switch rows with columns and produce another valid puzzle. If you have a valid puzzle you can switch 2 rows in the same block and produce another valid puzzle. Once you know these 2 concepts, you do not need to belabor all the different patterns for a solving technique.

@nouraalwani1245 Ай бұрын

I think that your explanation for calling this method an empty rectangle is wrong. The empty rectangle refers to the area that consists of the block , the conjugate pair, and the cell that has the number that would be eliminated. When you connect all these they create a rectangle shape.