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 10/10/08: C XY

 
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: Fri Oct 08, 2010 5:27 am    Post subject: Puzzle 10/10/08: C XY Reply with quote

Code:
 +-----------------------+
 | 7 . . | . 4 . | . . . |
 | . 4 6 | . 7 . | . . 8 |
 | . 2 3 | . 6 . | . 7 1 |
 |-------+-------+-------|
 | . . . | . 8 . | 3 . 4 |
 | 3 6 8 | 4 5 . | . 1 . |
 | . . . | . . 7 | 6 8 . |
 |-------+-------+-------|
 | . . . | 5 . 4 | . 3 . |
 | . . 7 | . 3 6 | 8 2 . |
 | . 3 5 | 7 . . | . . . |
 +-----------------------+

Play this puzzle online at the Daily Sudoku site
Back to top
View user's profile Send private message
JC Van Hay



Joined: 13 Jun 2010
Posts: 494
Location: Charleroi, Belgium

PostPosted: Fri Oct 08, 2010 9:09 am    Post subject: Reply with quote

Quote:
XY Wing Style : 8B1 5R3 (5=19)R1C26 : r1c2<>19
Remote Pairs (19) : r6c2<>19
BUG+2 : r1c4=1 or r1c6=9 -> r8c4=9
Back to top
View user's profile Send private message
peterj



Joined: 26 Mar 2010
Posts: 974
Location: London, UK

PostPosted: Fri Oct 08, 2010 9:20 pm    Post subject: Reply with quote

Found this one tough! Four steps with no basics between the first three...
Quote:
xy-chain ; (1=5)r2c1 - (5=2)r2c7 - (2=1)r2c4 - (1=9)r8c4 - (9=1)r8c2 ; r1c2<>1, r79c1<>1
remote pairs(19) grouped r8c2, r6c5 ; r6c2<>19=5
s-wing(89) ; (9)r8c2=r8c4 - (9=8)r3c4 - (8)r1c4=r1c2 ; r1c2<>9
skyscraper(9) ; r4c6<>9
Back to top
View user's profile Send private message
tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills

PostPosted: Fri Oct 08, 2010 9:40 pm    Post subject: Reply with quote

Three really fun steps.........

Quote:
Grouped RP(19) r8c2=>r8c4=>r79c5=>r6c5; r6c2<>19=5 (Fun but not needed. See next step.)
ANP(19=5)r1c36-(5=9r3c6*-(89=5)als:r3c14-(5=1)r2c1; r1c4*<>9,r1c2<>1
w-wing (89)r1c2 & r3c4 SL (9)r8c24; r1c4,r3c1<>8

Edit: Corrected error deletion of 5 in r1c2

Ted


Last edited by tlanglet on Fri Oct 08, 2010 11:59 pm; edited 1 time in total
Back to top
View user's profile Send private message
peterj



Joined: 26 Mar 2010
Posts: 974
Location: London, UK

PostPosted: Fri Oct 08, 2010 10:32 pm    Post subject: Reply with quote

Ted, interesting second move! I can see the elimination of...
(9)r1c4 since either (19)r1c36 or (9)r3c6; and...
(1)r1c2 since either (19)r1c36 or (1)r2c1; but...

I'm having a hard time to see the (5) elimination?

Just intuitively I don't see a fragment of your AIC that starts with "not a 5" and ends with "is a 5" that makes that elimination.
Back to top
View user's profile Send private message
tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills

PostPosted: Fri Oct 08, 2010 11:56 pm    Post subject: Reply with quote

peterj wrote:
Ted, interesting second move! I can see the elimination of...
(9)r1c4 since either (19)r1c36 or (9)r3c6; and...
(1)r1c2 since either (19)r1c36 or (1)r2c1; but...

I'm having a hard time to see the (5) elimination?

Just intuitively I don't see a fragment of your AIC that starts with "not a 5" and ends with "is a 5" that makes that elimination.


Peter, it is my move to be Embarassed Embarassed

After posting this result, I went outdoors to cut some more firewood to heat the house this winter and was suddenly struck by the fact that I messed up badly in handling that 5. My original solution included the three steps I posted, but then when I prepared the post I suddenly thought step 2 could delete the 5 in r1c2 and edited my post accordingly. I will edit my original post.

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