dailysudoku.com Forum Index dailysudoku.com
Discussion of Daily Sudoku puzzles
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Collection 4/17/12

 
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Other puzzles
View previous topic :: View next topic  
Author Message
arkietech



Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA
PostPosted: Tue Apr 17, 2012 5:37 am    Post subject: Collection 4/17/12 Reply with quote
Code:

 *-----------*
 |..5|...|.97|
 |..8|...|..5|
 |.4.|..6|2..|
 |---+---+---|
 |.1.|...|8..|
 |2..|3..|...|
 |3.7|.9.|...|
 |---+---+---|
 |.6.|8..|.42|
 |..4|..7|5..|
 |...|43.|...|
 *-----------*
 

Play/Print online
Back to top
View user's profile Send private message
tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
PostPosted: Tue Apr 17, 2012 2:37 pm    Post subject: Reply with quote
Code:
*-----------------------------------------------------------------------------*
 | 16      23      5       | 12      1248    12348   | 1346    9       7       |
 | 1679    2379    8       | 1279    1247    1234    | 1346    136     5       |
 | 79      4       13      | 579     57      6       | 2       138     138     |
 |-------------------------+-------------------------+-------------------------|
 | 4       1       69      | 2567    2567    25      | 8       23567   369     |
 | 2       58      69      | 3       145678  1458    | 1679    1567    1469    |
 | 3       58      7       | 1256    9       12458   | 16      1256    146     |
 |-------------------------+-------------------------+-------------------------|
 | 1579    6       13      | 8       15      159     | 1379    4       2       |
 | 189     39      4       | 26      26      7       | 5       138     1389    |
 | 15789   79      2       | 4       3       159     | 1679    1678    1689    |
 *-----------------------------------------------------------------------------*


I had some time this morning, and given the recent discussion on SdC, I specifically searched for one. I found an almost SdC but the extra digit is removed due to a conflict leaving a straightforward SdC pattern.

almost SdC(16789)r9c789
ab=(79)r9c2
cd=(18)r8c8
e=(6)r9c789
Fin(3)r8c8
If SdC is true then: r9c1<>7, r9c16<>9, r7c7,r8c9<>1, r8c9<>8

If fin is true then:
(3)r8c8-r*34c8=r4c9-r3c98*=r3c3-r7c3=r8c2; CONFLICT => r8c8<>3 thus the SdC it true

Edited to add comment: This step does not solve the puzzle.

Ted
Back to top
View user's profile Send private message
arkietech



Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA
PostPosted: Tue Apr 17, 2012 3:15 pm    Post subject: Reply with quote
No SdC Crying or Very sad but I'm looking Shocked
Code:
 *-----------------------------------------------------------------------------*
 | 16      23      5       | 12      1248    12348   | 146-3   9       7       |
 | 1679    2379    8       | 1279    1247    1234    | 146-3   136     5       |
 | 79      4      b13      | 579     57      6       | 2      a138    a138     |
 |-------------------------+-------------------------+-------------------------|
 | 4       1       69      | 2567    2567    25      | 8       23567   369     |
 | 2       58      69      | 3       145678  1458    | 1679    1567    1469    |
 | 3       58      7       | 1256    9       12458   | 16      1256    146     |
 |-------------------------+-------------------------+-------------------------|
 | 1579    6      c13      | 8       15      159     |d1379    4       2       |
 | 189     39      4       | 26      26      7       | 5       138     1389    |
 | 15789   79      2       | 4       3       159     | 1679    1678    1689    |
 *-----------------------------------------------------------------------------*
sashimi X-Wing (3)r3c89=r3c3-r7c3=(3)r7c7 => r12c7<>3;
stte

Play/Print online
Back to top
View user's profile Send private message
Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
PostPosted: Tue Apr 17, 2012 4:44 pm    Post subject: Reply with quote
Same Sashimi as Dan.
Back to top
View user's profile Send private message
DonM



Joined: 15 Sep 2009
Posts: 51
PostPosted: Tue Apr 17, 2012 5:59 pm    Post subject: Reply with quote
tlanglet wrote:
Code:
*-----------------------------------------------------------------------------*
 | 16      23      5       | 12      1248    12348   | 1346    9       7       |
 | 1679    2379    8       | 1279    1247    1234    | 1346    136     5       |
 | 79      4       13      | 579     57      6       | 2       138     138     |
 |-------------------------+-------------------------+-------------------------|
 | 4       1       69      | 2567    2567    25      | 8       23567   369     |
 | 2       58      69      | 3       145678  1458    | 1679    1567    1469    |
 | 3       58      7       | 1256    9       12458   | 16      1256    146     |
 |-------------------------+-------------------------+-------------------------|
 | 1579    6       13      | 8       15      159     | 1379    4       2       |
 | 189     39      4       | 26      26      7       | 5       138     1389    |
 | 15789   79      2       | 4       3       159     | 1679    1678    1689    |
 *-----------------------------------------------------------------------------*


I had some time this morning, and given the recent discussion on SdC, I specifically searched for one. I found an almost SdC but the extra digit is removed due to a conflict leaving a straightforward SdC pattern.

almost SdC(16789)r9c789
ab=(79)r9c2
cd=(18)r8c8
e=(6)r9c789
Fin(3)r8c8
If SdC is true then: r9c1<>7, r9c16<>9, r7c7,r8c9<>1, r8c9<8> r8c8<>3 thus the SdC it true

Edited to add comment: This step does not solve the puzzle.

Ted


Almost SDCs are relatively frequent. In easier puzzles, they can often be helpful. In more difficult puzzles, they don't necessarily solve the puzzle and not infrequently they aren't helpful, but every so often they can provide a crucial link.

Since I gave my SDC link elsewhere here, I might as well give the related Almost-SDC links:

http://forum.enjoysudoku.com/the-almost-sue-de-coq-asi-2-t6411.html
http://forum.enjoysudoku.com/the-almost-sue-de-coq-part-2-asi-2b-t6462.html
http://forum.enjoysudoku.com/solving-with-almost-sue-de-coq-extreme-118-asi-2c-t6563.html
http://forum.enjoysudoku.com/solving-with-almost-sue-de-coq-extreme-122-asi-2d-t6564.html
Back to top
View user's profile Send private message
Luke451



Joined: 20 Apr 2008
Posts: 310
Location: Southern Northern California
PostPosted: Tue Apr 17, 2012 7:00 pm    Post subject: Reply with quote
@ arkietech: Dan, just a quick thank you for your tireless efforts in posting puzzles every day. You are keeping us afloat and I'm very appreciative!

@ tlanglet: Nice, an almost SdC w/memory. Don't see that every day....

...unless you're DonM, king of the SdQ/aSdQ Very Happy

See Don's post in a recent thread over yonder for this concept in action.

Oh, and thanks for all the links, Don. Nice to get back up to speed on this fun stuff.
Back to top
View user's profile Send private message
Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
PostPosted: Tue Apr 17, 2012 9:43 pm    Post subject: Reply with quote
Quote:
@ arkietech: Dan, just a quick thank you for your tireless efforts in posting puzzles every day. You are keeping us afloat and I'm very appreciative!


Dan, Luke's not alone with that thought!
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Other puzzles All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group