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 

March 15 VH

 
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Daily Sudoku puzzles
View previous topic :: View next topic  
Author Message
Earl



Joined: 30 May 2007
Posts: 677
Location: Victoria, KS

PostPosted: Sun Mar 15, 2009 3:38 am    Post subject: March 15 VH Reply with quote

One shot. (389) xy-wing.

Early Earl
Back to top
View user's profile Send private message Send e-mail
swando



Joined: 09 Mar 2009
Posts: 17
Location: Surrey, BC. Canada

PostPosted: Sun Mar 15, 2009 9:48 am    Post subject: Reply with quote

389 it was!
Back to top
View user's profile Send private message Send e-mail Visit poster's website
cgordon



Joined: 04 May 2007
Posts: 769
Location: ontario, canada

PostPosted: Sun Mar 15, 2009 1:31 pm    Post subject: Reply with quote

I don't like looking for xy wings - too painful. So for me it was an x-wing on <3>: two Type 4 URs (15) and (49) and another x-wing on <9>.
Back to top
View user's profile Send private message
Clement



Joined: 24 Apr 2006
Posts: 1110
Location: Dar es Salaam Tanzania

PostPosted: Sun Mar 15, 2009 1:33 pm    Post subject: Reply with quote

I used two XY-Wings:-
1) XY-Wing {359} with Pivot {5,3}r5c5 eliminating 9 in r8c2
2) XY-Wing {389} with Pivot {3,8}r5c3 eliminating 9 in r7c2 solves the puzzle. However, the 389 XY-wing was enough.
Back to top
View user's profile Send private message AIM Address
Louise56



Joined: 21 Sep 2005
Posts: 94
Location: El Cajon, California USA

PostPosted: Tue Mar 24, 2009 2:46 pm    Post subject: 15 March VH XY wing Reply with quote

Could someone explain to me the 389 XY wing in this puzzle? I understand the XY wing when it is a rectangle, but this one appears not to be. I couldn't solve the puzzle. Thanks!
Back to top
View user's profile Send private message
wapati



Joined: 10 Jun 2008
Posts: 472
Location: Brampton, Ontario, Canada.

PostPosted: Tue Mar 24, 2009 3:06 pm    Post subject: Re: 15 March VH XY wing Reply with quote

Louise56 wrote:
Could someone explain to me the 389 XY wing in this puzzle? I understand the XY wing when it is a rectangle, but this one appears not to be. I couldn't solve the puzzle. Thanks!


The cell marked with "@" can only be a 3 or an 8.
That means that one of the cells marked with a "#" must be a 9.
All the cells marked with a "/" cannot be a 9 because they "see" both 9s. Smile

Code:
.---------------------.---------------------.---------------------.
| 489    5      389   | 3489   2      3489  | 1      6      7     |
| 4789   389    1     | 34789  39     6     | 34     2      5     |
| 47     6      2     | 3457   1      3457  | 34     8      9     |
:---------------------+---------------------+---------------------:
| 5      2      /4    | 89     7      89    | 6      3      1     |
| 19    #39     /6    | 135    35     2     | 8      7      4     |
| 18     7     @38    | 6      4      13    | 5      9      2     |
:---------------------+---------------------+---------------------:
| 3      /49    7     | 1459   8      1459  | 2      15     6     |
| 6      /489  #89    | 2      59     1459  | 7      15     3     |
| 2      /1     5     | 37     6      37    | 9      4      8     |
'---------------------'---------------------'---------------------'
Back to top
View user's profile Send private message
Louise56



Joined: 21 Sep 2005
Posts: 94
Location: El Cajon, California USA

PostPosted: Tue Mar 24, 2009 5:15 pm    Post subject: Reply with quote

Thank-you Wapati for a great explanation. I have always had a mental block with y wings. It's hard to locate them, but your logic is clear and simple.
Back to top
View user's profile Send private message
wapati



Joined: 10 Jun 2008
Posts: 472
Location: Brampton, Ontario, Canada.

PostPosted: Tue Mar 24, 2009 5:16 pm    Post subject: Reply with quote

Very Happy
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Daily Sudoku 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