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Puzzle 11/06/22: ~ Extreme

 
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Wed Jun 22, 2011 5:42 pm    Post subject: Puzzle 11/06/22: ~ Extreme Reply with quote

I wanted to generate more Advanced puzzles but, inadvertantly, left my puzzle generator configured for XY puzzles. This one popped out as an excessive XY puzzle. Enjoy!

Code:
 +-----------------------+
 | . 8 3 | . 4 . | . . . |
 | 6 7 1 | . . 5 | . . 8 |
 | 2 4 . | . . . | . . . |
 |-------+-------+-------|
 | . . . | . 2 9 | . 5 . |
 | 5 . . | 3 1 4 | . 6 . |
 | . 6 . | 5 8 . | 9 . . |
 |-------+-------+-------|
 | . . . | . . 3 | 6 1 . |
 | . . . | 4 9 . | 2 8 . |
 | . 3 . | . . . | . . 9 |
 +-----------------------+

Play this puzzle online at the Daily Sudoku site
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peterj



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

PostPosted: Wed Jun 22, 2011 8:20 pm    Post subject: Reply with quote

Not sure how to reconcile this with "extreme" - guess more than two links in a turbot/xchain not prioritised by your solver?
Quote:
colouring(2)/xchain ; (2)r6c3=r6c8 - r2c8=r2c4 - r1c6=r9c6 ; r9c3<>2
kite(4) ; (4)r7c1=r7c9 - r9c8=r6c8 ; r6c1<>4
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tlanglet



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

PostPosted: Wed Jun 22, 2011 9:47 pm    Post subject: Reply with quote

Here is my two cents.........

Quote:
axy-wing (27-6) vertex (27)r1c8 with fin (1)r1c6; r1c9,r3c5<>6
xy-wing=(1)r1c6-als(1=5)r1c487-(5=7)r9c7-r9c8=r1c8-(7=6)r3c9;

Coloring (4) completes the puzzle.

Ted
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Wed Jun 22, 2011 10:01 pm    Post subject: Reply with quote

peterj wrote:
Not sure how to reconcile this with "extreme" - guess more than two links in a turbot/xchain not prioritised by your solver?

Incorrect. Correct when you consider the fish techniques that I allow my solver to use on puzzles posted to this forum.

All of these techniques are 2-Fish as far as my solver is concerned:

Code:
turbot fish: 2-String Kite, Skyscraper, Empty Rectangle, finned/Sashimi X-Wing

Your X-Chain(2) uses three strong inferences, and thus qualifies as a 3-Fish/Swordfish variant by my solver. It wasn't "allowed" when considering techniques to solve the puzzle. Ironically, your X-Chain(2) was allowed by the old version of my solver used with the puzzle generator. It finds most fish eliminations through templates -- which doesn't resolve the number of strong inferences present.
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Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA

PostPosted: Sat Jun 25, 2011 4:29 am    Post subject: Reply with quote

I used my typical excess moves.

Multi-coloring (2)
Type 4 UR (29)
XYZ-Wing (478)
XY-Wing (267)
Coloring (4)
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PIsaacson



Joined: 13 Jun 2011
Posts: 11
Location: Campbell, CA

PostPosted: Sat Jun 25, 2011 7:44 am    Post subject: Reply with quote

Basics +
kite (7) r3c59 and r19c8 => r9c5 <> 7
UR Type 4 29 r57c23 => r57c3 <> 2
followed by 2 WXYZ-Wings
Code:
 *-----------------------------------------------------------*
 | 9     8     3     |a127   4    a126   | 157  a27    2567  |
 | 6     7     1     | 29    3     5     | 4     29    8     |
 | 2     4     5     | 189   67    8-1   | 13    39    67    |
 |-------------------+-------------------+-------------------|
 | 3478  1     478   | 6     2     9     | 378   5     47    |
 | 5     29    789   | 3     1     4     | 78    6     27    |
 | 34    6     24    | 5     8     7     | 9     234   1     |
 |-------------------+-------------------+-------------------|
 | 48    29    489   | 278   57    3     | 6     1     457   |
 | 17    5     67    | 4     9    b16    | 2     8     3     |
 | 148   3     2468  | 1278  56    1268  | 57    47    9     |
 *-----------------------------------------------------------*
     WXYZ-Wing ALS (a) r1c468 - 6 - (b) r8c6 => r3c6 <> 1
 *-----------------------------------------------------------*
 | 9     8     3     |a127   4     16-2  | 157  b27    2567  |
 | 6     7     1     |a29    3     5     | 4     29    8     |
 | 2     4     5     |a19    67    8     | 13    39    67    |
 |-------------------+-------------------+-------------------|
 | 3478  1     478   | 6     2     9     | 378   5     47    |
 | 5     29    789   | 3     1     4     | 78    6     27    |
 | 34    6     24    | 5     8     7     | 9     234   1     |
 |-------------------+-------------------+-------------------|
 | 48    29    489   | 278   57    3     | 6     1     457   |
 | 17    5     67    | 4     9     16    | 2     8     3     |
 | 148   3     2468  | 1278  56    126   | 57    47    9     |
 *-----------------------------------------------------------*
     WXYZ-Wing ALS (a) r123c4 - 7 - (b) r1c8 => r1c6 <> 2

Singles + one more kite (4) r6c18 and r49c3 => r9c8 <> 4 then ste

I'm uncertain where the WXYZ-Wing fits into the techniques priority scheme. It is sometimes called an extended XYZ-Wing or an ALS-XZ pattern. I like ALS patterns since they are ubiquitous and often crack really hard puzzles. Since this puzzle is in the extreme category, is it okay to use ALSs/DBs/SDCs???

Cheers,
Paul
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Sat Jun 25, 2011 4:24 pm    Post subject: Reply with quote

PIsaacson wrote:
I'm uncertain where the WXYZ-Wing fits into the techniques priority scheme. It is sometimes called an extended XYZ-Wing or an ALS-XZ pattern. I like ALS patterns since they are ubiquitous and often crack really hard puzzles. Since this puzzle is in the extreme category, is it okay to use ALSs/DBs/SDCs???

Paul, your solution is fine ... and thanks for the details! Also, it's okay to use ALS/DB/SdC/MUG and the extended "wings". Members also like to be creative with their UR steps as well. BTW: thanks for the detailed specifics for the WXYZ-Wings.

Regards, Danny
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