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XY-Wing compendium

 
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Nick70

Joined: 08 Jun 2005
Posts: 160
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PostPosted: Sat Jul 23, 2005 11:52 pm    Post subject: XY-Wing compendium Reply with quote

Here are a few puzzles that can be solved using the XY-Wing pattern. You might need to use other advanced techinques like X-Wing or Swordfish to solve some of them.

The puzzles are roughly in order of difficulty. YMMV.

Puzzle 1:

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


Puzzle 2:

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


Puzzle 3:

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


Puzzle 4:

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


Puzzle 5:

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


Puzzle 6:

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


Puzzle 7:

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


Puzzle 8:

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


Puzzle 9:

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


Puzzle 10:

Code:
 . . 9 | . 8 . | 7 . 6
 . 3 2 | 6 . . | . . .
 5 . . | . . . | . . .
-------+-------+-------
 . . . | . . 5 | . . .
 . . 8 | . 1 . | 2 . .
 . . . | 4 . . | . . .
-------+-------+-------
 . . . | . . . | . . 5
 . . . | . . 7 | 8 2 .
 7 . 1 | . 3 . | 6 . .
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Nick70

Joined: 08 Jun 2005
Posts: 160
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PostPosted: Sun Aug 07, 2005 9:51 am    Post subject: Reply with quote

This is a nice xy-wing puzzle.

My solver does 7 of them in a row, before finally being able to place a big number. Mind you, they might not be all needed Smile Still, it might be one of the best xy-wing examples to date--especially because it doesn't require any other advanced technique apart from a hidden pair (or a naked triple).

Code:
..9.4.8.1
.376.....
6........
.....5...
..8.1.7..
...4.....
........7
.....732.
5.4.2.9..
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angusj
Site Admin
Joined: 18 Jun 2005
Posts: 406
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PostPosted: Fri Sep 09, 2005 10:43 am    Post subject: Reply with quote

Nick70 wrote:
This is a nice xy-wing puzzle.


Perhaps you'll like this one too. Very Happy

Code:
 *-----------*
 |8.9|.6.|.2.|
 |...|..1|.9.|
 |.7.|...|..8|
 |---+---+---|
 |4..|..9|.52|
 |..2|.4.|9..|
 |98.|6..|..1|
 |---+---+---|
 |5..|...|.6.|
 |.9.|2..|...|
 |.2.|.8.|3.7|
 *-----------*
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Nick70

Joined: 08 Jun 2005
Posts: 160
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PostPosted: Fri Sep 09, 2005 11:53 am    Post subject: Reply with quote

Thanks Angus, really excellent. Lots of turbots and lots of xy-wings.
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angusj
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Joined: 18 Jun 2005
Posts: 406
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PostPosted: Fri Sep 09, 2005 12:27 pm    Post subject: Reply with quote

Nick70 wrote:
Thanks Angus, really excellent. Lots of turbots and lots of xy-wings.

I've got dozens of them if you want more Very Happy
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