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 

Puzzle 11/02/22 Fun Size

 
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Puzzles by daj
View previous topic :: View next topic  
Author Message
daj95376



Joined: 23 Aug 2008
Posts: 3854
PostPosted: Tue Feb 22, 2011 3:37 am    Post subject: Puzzle 11/02/22 Fun Size Reply with quote
Puzzles posted early because I'll be busy embarrassing myself trying the Patterns Game on Tuesday.

Code:
 +-----------------------+
 | . . 6 | . 8 9 | 5 7 . |
 | . 3 8 | 5 . 7 | . . 1 |
 | 4 5 . | 6 . 1 | 9 . . |
 |-------+-------+-------|
 | . 8 9 | 1 . . | . . . |
 | 3 . . | . 5 . | . . 7 |
 | 7 1 5 | . . . | . . 9 |
 |-------+-------+-------|
 | 6 . 1 | . . . | . . . |
 | 5 . . | . . . | . . 8 |
 | . 7 . | . 9 5 | . 1 6 |
 +-----------------------+

Play this puzzle online at the Daily Sudoku site
Back to top
View user's profile Send private message
Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
PostPosted: Wed Feb 23, 2011 1:46 am    Post subject: Reply with quote
Not sure which, if any, of my first two steps were necessary.

Quote:
Type 2 UR (23-4)
M-Wing (34); r4c9<>3 +transport; r6c4<>3
M-Wing (34); r7c9<>3
XY-Wing (254); r4c6<>4
Back to top
View user's profile Send private message
tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
PostPosted: Wed Feb 23, 2011 3:14 am    Post subject: Reply with quote
Quote:
Type 2 UR(23)r89c37; r24c7,b9q235<>4
xy-wing 34-6 vertex (34)r6c8; r2c7,r4c8<>6

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



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
PostPosted: Wed Feb 23, 2011 3:37 am    Post subject: Reply with quote
Code after basics:

Code:
*-----------------------------------------------------------*
 | 1     2     6     | 34    8     9     | 5     7     34    |
 | 9     3     8     | 5     24    7     | 246   46    1     |
 | 4     5     7     | 6     23    1     | 9     8     23    |
 |-------------------+-------------------+-------------------|
 | 2     8     9     | 1     7     34    | 346   3456  45    |
 | 3     6     4     | 9     5     8     | 1     2     7     |
 | 7     1     5     | 234   6     234   | 8     34    9     |
 |-------------------+-------------------+-------------------|
 | 6     49    1     | 8     34    234   | 7     3459  245   |
 | 5     49   #23    | 7     1     6     |#234   349   8     |
 | 8     7    #23    | 234   9     5     |#234   1     6     |
 *-----------------------------------------------------------*


Notice the Type 2 UR(23)r89c37 marked #.
To prevent the deadly UR, r8c7=4 or r9c7=4; thus r24c7,r7c89,r8c8<>4

This is a nice move, but we miss some more deletions if we proceed to other patterns. Instead, if we look at the external implications we find that to prevent the deadly UR pattern r2c7=2 or r4c7=3.

Thus: (4=3)r4c7-UR(23)r89c37[(3)r4c7=(2)r2c7]-(2=4)r2c5-r1c4=r1c9; r4c9<>4 which completes the puzzle.

Ted
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Puzzles by daj 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