Thread - stuck in this sudoku

@ 2015-11-15 6:13 AM (#19947 - in reply to #19946) (#19947) Top

swaroop2011

Posts: 668

Country : India

swaroop2011 posted @ 2015-11-15 6:13 AM

ghirsch - 2015-11-15 4:47 AM

I've been working my way through Thomas Snyder's Art of Sudoku book, and I'm pretty stuck on this one. Can anyone help me out (preferably with just a step or two to get me on the right track)? I'm probably just missing something obvious but I can't seem to come up with any ideas for what to do.

9 at r7c7 due to 34 pair at r1c7 and r6c7

Edited by swaroop2011 2015-11-15 6:13 AM

@ 2015-11-15 6:39 AM (#19948 - in reply to #8611) (#19948) Top

ghirsch

Posts: 102

Country : United States

ghirsch posted @ 2015-11-15 6:39 AM

Thanks Swaroop, that did the trick. It's a pretty tough deduction to find though, I guess I still need more practice.

@ 2016-04-05 1:38 PM (#21433 - in reply to #8611) (#21433) Top

kishy72

Posts: 419

Country : India

kishy72 posted @ 2016-04-05 1:38 PM

Anti-diagonal from the Russian GP .I solved this particular sudoku for a long time and had to guess to finish it .Could someone tell me how to continue logically here ?

Edited by kishy72 2016-04-05 1:39 PM

@ 2016-04-05 6:00 PM (#21436 - in reply to #21433) (#21436) Top

rajeshk

Posts: 542

Country : India

rajeshk posted @ 2016-04-05 6:00 PM

kishy72 - 2016-04-05 1:38 PM

Anti-diagonal from the Russian GP .I solved this particular sudoku for a long time and had to guess to finish it .Could someone tell me how to continue logically here ?

Center has to be 1. In case we put 7 there then there will be no place left to put 7 in 6th Box.

@ 2019-10-25 1:25 PM (#27343 - in reply to #8611) (#27343) Top

kishy72

Posts: 419

Country : India

kishy72 posted @ 2019-10-25 1:25 PM

The following sudoku is from CSOC 63 PB.I couldn't understand the English version of the rules given in the example image.I assumed it to be a clone sudoku and started solving like that in contest.However, it quickly broke after that.

Can someone clarify what the rules imply ?

(CP.png)

(IB.png)

Attachments
----------------

CP.png (61KB - 1 downloads)
Attachments

IB.png (100KB - 0 downloads)

@ 2019-10-25 1:40 PM (#27344 - in reply to #8611) (#27344) Top

kishy72

Posts: 419

Country : India

kishy72 posted @ 2019-10-25 1:40 PM

Also, can the admin kindly specify alternate websites for uploading images here ? Earlier, I used to upload from tinypic which seems to have shut down now.
The images posted above are screenshots and are too big and uncomfortable looking.

@ 2019-10-26 7:23 PM (#27348 - in reply to #8611) (#27348) Top

xiao01wei

Posts: 6

Country : China

xiao01wei posted @ 2019-10-26 7:23 PM

CSOC 63 P13's rule:
if there is two same shape, for example, two vertical domino shape, there will be 4 numbers in these 2 shapes:
A C
B D
and
if A>B, and then the result is C>D at the same time
if A<B, and then the result is C<D at the same time
if C>D, and then the result is A>B at the same time
if C<D, and then the result is A<B at the same time
the same inequality between the four numbers in two shapes with corresponding position

Edited by xiao01wei 2019-10-26 7:30 PM

@ 2019-10-26 11:38 PM (#27350 - in reply to #27348) (#27350) Top

kishy72

Posts: 419

Country : India

kishy72 posted @ 2019-10-26 11:38 PM

xiao01wei - 2019-10-26 7:23 PM

CSOC 63 P13's rule:
if there is two same shape, for example, two vertical domino shape, there will be 4 numbers in these 2 shapes:
A C
B D
and
if A>B, and then the result is C>D at the same time
if A if C>D, and then the result is A>B at the same time
if C the same inequality between the four numbers in two shapes with corresponding position

Thanks a lot Xiao Wei for the clarification ! I finished the sudoku now.It is certainly an interesting variant and I will look forward to seeing more of it in future.

@ 2019-11-23 12:36 PM (#27362 - in reply to #8611) (#27362) Top

kishy72

Posts: 419

Country : India

kishy72 posted @ 2019-11-23 12:36 PM

Little Killer from LMD portal by 'Realshaggy'

This sudoku is pure evil.I tried everything that I usually encounter in Little Killer Sudokus from totalling clues,seeing min-max possibilities, clue interaction etc., but this sudoku just yielded nothing.I have been trying for the past week or so to complete this without success.It's kind of demotivating in a way that after so many years of solving sudoku, there are still some that I am unable to be complete. Kindly someone share the break-in for this ' psycho little killer '.

(LK.jpg)

Attachments
----------------

LK.jpg (45KB - 2 downloads)

@ 2019-11-23 6:15 PM (#27363 - in reply to #8611) (#27363) Top

Puzzle_Maestro

Posts: 25

Country : United Kingdom

Puzzle_Maestro posted @ 2019-11-23 6:15 PM

If you add up the clues on the top and bottom rows, you get 369. Adding up the clues in the left and right gives 327. The difference between the two is 42.

Observe that the arrows on the left and right point to 6 cells which are not pointed to by the arrows on top and bottom (with minimum sum 3*(1+2)=9), and similarly the arrows on top and bottom point to 6 cells not pointed to by arrows on the left and right (maximum sum 3*(8+9)=51). The difference between them must be 42, and since the maximum difference between them is 42, we can establish a few 12 and 89 pairs.

@ 2019-11-25 8:52 AM (#27364 - in reply to #27363) (#27364) Top

kishy72

Posts: 419

Country : India

kishy72 posted @ 2019-11-25 8:52 AM

Puzzle_Maestro - 2019-11-23 6:15 PM

If you add up the clues on the top and bottom rows, you get 369. Adding up the clues in the left and right gives 327. The difference between the two is 42.

Observe that the arrows on the left and right point to 6 cells which are not pointed to by the arrows on top and bottom (with minimum sum 3*(1+2)=9), and similarly the arrows on top and bottom point to 6 cells not pointed to by arrows on the left and right (maximum sum 3*(8+9)=51). The difference between them must be 42, and since the maximum difference between them is 42, we can establish a few 12 and 89 pairs.

Thanks a lot ! I could complete it with your pointer.


	@ 2015-11-15 6:13 AM (#19947 - in reply to #19946) (#19947) Top
swaroop2011 Posts: 668 Country : India	swaroop2011 posted @ 2015-11-15 6:13 AM ghirsch - 2015-11-15 4:47 AM I've been working my way through Thomas Snyder's Art of Sudoku book, and I'm pretty stuck on this one. Can anyone help me out (preferably with just a step or two to get me on the right track)? I'm probably just missing something obvious but I can't seem to come up with any ideas for what to do. 9 at r7c7 due to 34 pair at r1c7 and r6c7 Edited by swaroop2011 2015-11-15 6:13 AM
	@ 2015-11-15 6:39 AM (#19948 - in reply to #8611) (#19948) Top
ghirsch Posts: 102 Country : United States	ghirsch posted @ 2015-11-15 6:39 AM Thanks Swaroop, that did the trick. It's a pretty tough deduction to find though, I guess I still need more practice.
	@ 2016-04-05 1:38 PM (#21433 - in reply to #8611) (#21433) Top
kishy72 Posts: 419 Country : India	kishy72 posted @ 2016-04-05 1:38 PM Anti-diagonal from the Russian GP .I solved this particular sudoku for a long time and had to guess to finish it .Could someone tell me how to continue logically here ? Edited by kishy72 2016-04-05 1:39 PM
	@ 2016-04-05 6:00 PM (#21436 - in reply to #21433) (#21436) Top
rajeshk Posts: 542 Country : India	rajeshk posted @ 2016-04-05 6:00 PM kishy72 - 2016-04-05 1:38 PM Anti-diagonal from the Russian GP .I solved this particular sudoku for a long time and had to guess to finish it .Could someone tell me how to continue logically here ? Center has to be 1. In case we put 7 there then there will be no place left to put 7 in 6th Box.
	@ 2019-10-25 1:25 PM (#27343 - in reply to #8611) (#27343) Top
kishy72 Posts: 419 Country : India	kishy72 posted @ 2019-10-25 1:25 PM The following sudoku is from CSOC 63 PB.I couldn't understand the English version of the rules given in the example image.I assumed it to be a clone sudoku and started solving like that in contest.However, it quickly broke after that. Can someone clarify what the rules imply ? (CP.png) (IB.png) Attachments ---------------- CP.png (61KB - 1 downloads) IB.png (100KB - 0 downloads)
	@ 2019-10-25 1:40 PM (#27344 - in reply to #8611) (#27344) Top
kishy72 Posts: 419 Country : India	kishy72 posted @ 2019-10-25 1:40 PM Also, can the admin kindly specify alternate websites for uploading images here ? Earlier, I used to upload from tinypic which seems to have shut down now. The images posted above are screenshots and are too big and uncomfortable looking.
	@ 2019-10-26 7:23 PM (#27348 - in reply to #8611) (#27348) Top
xiao01wei Posts: 6 Country : China	xiao01wei posted @ 2019-10-26 7:23 PM CSOC 63 P13's rule: if there is two same shape, for example, two vertical domino shape, there will be 4 numbers in these 2 shapes: A C B D and if A>B, and then the result is C>D at the same time if A<B, and then the result is C<D at the same time if C>D, and then the result is A>B at the same time if C<D, and then the result is A<B at the same time the same inequality between the four numbers in two shapes with corresponding position Edited by xiao01wei 2019-10-26 7:30 PM
	@ 2019-10-26 11:38 PM (#27350 - in reply to #27348) (#27350) Top
kishy72 Posts: 419 Country : India	kishy72 posted @ 2019-10-26 11:38 PM xiao01wei - 2019-10-26 7:23 PM CSOC 63 P13's rule: if there is two same shape, for example, two vertical domino shape, there will be 4 numbers in these 2 shapes: A C B D and if A>B, and then the result is C>D at the same time if A if C>D, and then the result is A>B at the same time if C the same inequality between the four numbers in two shapes with corresponding position Thanks a lot Xiao Wei for the clarification ! I finished the sudoku now.It is certainly an interesting variant and I will look forward to seeing more of it in future.
	@ 2019-11-23 12:36 PM (#27362 - in reply to #8611) (#27362) Top
kishy72 Posts: 419 Country : India	kishy72 posted @ 2019-11-23 12:36 PM Little Killer from LMD portal by 'Realshaggy' This sudoku is pure evil.I tried everything that I usually encounter in Little Killer Sudokus from totalling clues,seeing min-max possibilities, clue interaction etc., but this sudoku just yielded nothing.I have been trying for the past week or so to complete this without success.It's kind of demotivating in a way that after so many years of solving sudoku, there are still some that I am unable to be complete. Kindly someone share the break-in for this ' psycho little killer '. (LK.jpg) Attachments ---------------- LK.jpg (45KB - 2 downloads)
	@ 2019-11-23 6:15 PM (#27363 - in reply to #8611) (#27363) Top
Puzzle_Maestro Posts: 25 Country : United Kingdom	Puzzle_Maestro posted @ 2019-11-23 6:15 PM If you add up the clues on the top and bottom rows, you get 369. Adding up the clues in the left and right gives 327. The difference between the two is 42. Observe that the arrows on the left and right point to 6 cells which are not pointed to by the arrows on top and bottom (with minimum sum 3(1+2)=9), and similarly the arrows on top and bottom point to 6 cells not pointed to by arrows on the left and right (maximum sum 3(8+9)=51). The difference between them must be 42, and since the maximum difference between them is 42, we can establish a few 12 and 89 pairs.
	@ 2019-11-25 8:52 AM (#27364 - in reply to #27363) (#27364) Top
kishy72 Posts: 419 Country : India	kishy72 posted @ 2019-11-25 8:52 AM Puzzle_Maestro - 2019-11-23 6:15 PM If you add up the clues on the top and bottom rows, you get 369. Adding up the clues in the left and right gives 327. The difference between the two is 42. Observe that the arrows on the left and right point to 6 cells which are not pointed to by the arrows on top and bottom (with minimum sum 3(1+2)=9), and similarly the arrows on top and bottom point to 6 cells not pointed to by arrows on the left and right (maximum sum 3(8+9)=51). The difference between them must be 42, and since the maximum difference between them is 42, we can establish a few 12 and 89 pairs. Thanks a lot ! I could complete it with your pointer.