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 11/08/12: ~ XY (BBDB?)

 
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: 3855

PostPosted: Fri Aug 12, 2011 6:18 pm    Post subject: Puzzle 11/08/12: ~ XY (BBDB?) Reply with quote

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

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



Joined: 13 May 2011
Posts: 36
Location: Southeastern US

PostPosted: Fri Aug 12, 2011 10:02 pm    Post subject: Reply with quote

Quote:
X wing 7 r34c59; r34c16<>7
X wing 2 r34c19; r34c5<>2
DP (26)(67)(27)r34c159; r4c5=1
Back to top
View user's profile Send private message
ronk



Joined: 07 May 2006
Posts: 397

PostPosted: Fri Aug 12, 2011 11:25 pm    Post subject: Reply with quote

susume wrote:
Quote:
DP (26)(67)(27)r34c159; r4c5=1

susume, the rows need to "play" in the same band.
Back to top
View user's profile Send private message
susume



Joined: 13 May 2011
Posts: 36
Location: Southeastern US

PostPosted: Sat Aug 13, 2011 12:05 am    Post subject: Reply with quote

I think you mean I used too many boxes? Bother. Thanks for setting me straight.

edit: Hopefully this will recover a shred or two of my dignity:

X wing 7 r34c59
X wing 2 r34c19
S wing 72 (7)r4c9 =r4c5 -(7=2)r6c6 -r5c4 =(2)r5c7; r4c9<>2=7

If that's another blunder, I'll just crawl under a rock for a while.

~Sue
Back to top
View user's profile Send private message
peterj



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

PostPosted: Sat Aug 13, 2011 7:30 am    Post subject: Reply with quote

A move with unexpextedly lucky consequence Exclamation

I found this x-cycle/fish...
Code:
(6)r5c4=r1c4 - r3c5=r3c1 - r4c1=r4c56 -loop => (6)r4c56=r5c4

...but its impact is on the als(27) in r4 and b6...
Code:
als(27=6)r4c19 - (6)r4c56=r5c4 - als(6=27)r5c7|r4c9 ; r12c6<>6, r26c1<>6, r6c6<>6, r4c56<>7

(In fact the last strong link on 6 is extraneous for the eliminations on 7 but more fun!)

[dajEdit: corrected mismarked cells.]
Back to top
View user's profile Send private message
ronk



Joined: 07 May 2006
Posts: 397

PostPosted: Sat Aug 13, 2011 1:00 pm    Post subject: Reply with quote

Almost the same as susume's ...

x-wing(7)c59\r34 ==> r3c138, r4c16<>7
x-wing(2)c19\r34 ==> r3c2358, r4c56<>2
w-wing: (2=6)r4c1 - r6c23 = r6c8 - (6=2)r5c7 ==> r4c9<>2 ste

It took a few naked pair and locked candidate moves too, but it appears accepted practice is to not list basic moves. If this is correct, where is the line drawn?

I used the iPad app 'EnjoySudoku' (by JasonLion) while sitting outside with the dogs. Very nice fun-to-use app. One drawback: I didn't find a way to copy&paste the puzzle.
Back to top
View user's profile Send private message
Luke451



Joined: 20 Apr 2008
Posts: 310
Location: Southern Northern California

PostPosted: Sat Aug 13, 2011 1:59 pm    Post subject: Reply with quote

susume wrote:
I think you mean I used too many boxes? Bother. Thanks for setting me straight.

edit: Hopefully this will recover a shred or two of my dignity:

X wing 7 r34c59
X wing 2 r34c19
S wing 72 (7)r4c9 =r4c5 -(7=2)r6c6 -r5c4 =(2)r5c7; r4c9<>2=7

If that's another blunder, I'll just crawl under a rock for a while.

~Sue
Nice recovery!

Don't feel bad at all for mistakes. Posting public blunders is how I learned half of what little I know. Even when one is right, others can point out nuance or improvements that flesh out one's understanding of things.

The three horizontal chutes in a grid are called bands.
The three vertical chutes are called stacks.
The DP you were going for was a BUG-Lite and that type of BUG-Lite is confined to the three boxes of a band or stack.
Back to top
View user's profile Send private message
daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Sat Aug 13, 2011 3:03 pm    Post subject: Reply with quote

ronk wrote:
It took a few naked pair and locked candidate moves too, but it appears accepted practice is to not list basic moves. If this is correct, where is the line drawn?

The Basics from my ratings list are used to draw the line.
Back to top
View user's profile Send private message
Marty R.



Joined: 12 Feb 2006
Posts: 5065
Location: Rochester, NY, USA

PostPosted: Sun Aug 14, 2011 4:32 am    Post subject: Reply with quote

Potential 16 DP, boxes 58, common outcomes; r4c9, r6c6 = 7.
Back to top
View user's profile Send private message
peterj



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

PostPosted: Sun Aug 14, 2011 9:00 am    Post subject: Reply with quote

Marty R. wrote:
Potential 16 DP, boxes 58, common outcomes; r4c9, r6c6 = 7.

Marty, for others who are a bit "telepathically challenged" I had a go at writing this move down for the "non notationally challenged" Wink
Code:
ur(16)r48c56
(6)r4c1 - r3c1=r3c5 - r1c4=r5c4 - (6=2)r5c7 ; r4c9<>2=7
||
(6)r7c5 - r3c5=r3c1 - (6=27)r4c19 - (7)r4c5=r3c5 - (7=2)r3c9 ; r4c9<>2=7
At least for 4c9... I think!

Last edited by peterj on Sun Aug 14, 2011 5:05 pm; edited 1 time in total
Back to top
View user's profile Send private message
Marty R.



Joined: 12 Feb 2006
Posts: 5065
Location: Rochester, NY, USA

PostPosted: Sun Aug 14, 2011 3:56 pm    Post subject: Reply with quote

peterj wrote:
Marty R. wrote:
Potential 16 DP, boxes 58, common outcomes; r4c9, r6c6 = 7.

Marty, for others who are a bit "telepathically challenged" I had a go at writing this move down for the "non notationally challenged" Wink
Code:
ur(16)r48c56
(6)r4c1 - r3c1=r3c5 - r1c4=r5c4 - (6=2)r5c6 ; r4c9<>2=7
||
(6)r7c5 - r3c5=r3c1 - (6=27)r4c19 - (7)r4c5=r3c5 - (7=2)r3c9 ; r4c9<>2=7
At least for 4c9... I think!

Well, your response is much more satisfying than what I often get (euphemistically) from various members, "Marty, I'm unable to replicate your solution."

I don't understand why a 6 is at the start of each notation line, since the UR was 16 and I was testing other numbers, a so-called "internal analysis."

Also, what does that symbol mean, the parallel bars between the two lines of notation?
Back to top
View user's profile Send private message
susume



Joined: 13 May 2011
Posts: 36
Location: Southeastern US

PostPosted: Sun Aug 14, 2011 4:00 pm    Post subject: Reply with quote

Thank you Peter, and nice find, Marty.

Peter, where you have (6=2)r5c6 I wonder if you mean (6=2)r5c7?

~Sue

edit: The double bar || is a sideways equal sign, or strong link. Here it means "Either (6)r4c1 is true or (6)r7c5 is true" (those being the cells that can break the DP by pulling a 6 out of it, and for which Peter found matching outcomes).
Back to top
View user's profile Send private message
peterj



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

PostPosted: Sun Aug 14, 2011 5:09 pm    Post subject: Reply with quote

Susume, thanks for pointing out the typo - my second on this puzzle!

Marty, as Sue indicated it seemed easier using an "external analysis" rather than an internal one - but maybe not, I didn't really look.
Back to top
View user's profile Send private message
Marty R.



Joined: 12 Feb 2006
Posts: 5065
Location: Rochester, NY, USA

PostPosted: Sun Aug 14, 2011 7:39 pm    Post subject: Reply with quote

OK, I did the basics again via Draw/Play and came up with this:

Code:

+------------------+--------------+---------------+
| 8    2346 24567  | 26 9    2567 | 2356 24567 1  |
| 2367 9    2567   | 1  4    2567 | 2356 2567  8  |
| 267  1246 124567 | 3  267  8    | 2569 24567 27 |
+------------------+--------------+---------------+
| 267  5    9      | 4  1267 1267 | 8    3     27 |
| 4    8    17     | 26 3    9    | 26   17    5  |
| 2367 1236 1267   | 8  5    267  | 4    1267  9  |
+------------------+--------------+---------------+
| 5    26   8      | 7  26   3    | 1    9     4  |
| 9    246  246    | 5  126  126  | 7    8     3  |
| 1    7    3      | 9  8    4    | 25   25    6  |
+------------------+--------------+---------------+

Play this puzzle online at the Daily Sudoku site

I didn't see at the time that an external analysis could be done using just two possible 6s. With my internal, I had the 2s, of course, in r8c56 and the pseudo cell 27 (is that a quantum pair?) in r4. Thanks for clarifying things Peter.
Back to top
View user's profile Send private message
Marty R.



Joined: 12 Feb 2006
Posts: 5065
Location: Rochester, NY, USA

PostPosted: Sun Aug 14, 2011 7:41 pm    Post subject: Reply with quote

susume wrote:
Quote:
X wing 7 r34c59; r34c16<>7
X wing 2 r34c19; r34c5<>2
DP (26)(67)(27)r34c159; r4c5=1

Susume, not that it's a big deal, but most of us have stopped using the whiteout on the theory that we don't read the threads until after we do the puzzle.
Back to top
View user's profile Send private message
daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Mon Aug 15, 2011 2:24 am    Post subject: Reply with quote

Marty R. wrote:
Code:
ur(16)r48c56
(6)r4c1 - r3c1=r3c5 - r1c4=r5c4 - (6=2)r5c6 ; r4c9<>2=7
||
(6)r7c5 - r3c5=r3c1 - (6=27)r4c19 - (7)r4c5=r3c5 - (7=2)r3c9 ; r4c9<>2=7

Also, what does that symbol mean, the parallel bars between the two lines of notation?

The parallel bars mean ... OR. In this case, they mean: either r4c1=6 or r7c5=6 must be true.
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