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Hard puzzles, chains are not required. Rarely, ALS is.
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Jean-Christophe

Joined: 19 Mar 2006
Posts: 126
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Location: Belgium

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PostPosted: Mon Jul 07, 2008 8:41 pm    Post subject: Reply with quote

Interseting puzzle, which can be unlocked with only one advanced move. After simple steps and a sashimi X-Wing (skyscraper) we get:
Code:
+-------------------+-------------------+-------------------+
| 368   5     1     | 2     *369  7     | *89   4     3689  |
| 9     36    27    | 8     *36   4     | 27    1     5     |
| 3678  2346  2478  | 1     5     369   | 2789  378   3689  |
+-------------------+-------------------+-------------------+
| 2     7     9     | 34    *368  368   | 4-8   5     1     |
| 5     1     3     | 49    7     89    | 6     2     48    |
| 4     8     6     | 5     2     1     | 3     9     7     |
+-------------------+-------------------+-------------------+
| 3678  2346  2478  | 39    1     389   | 5     378   3489  |
| 1     34    478   | 6     3489  5     | 4789  378   2     |
| 38    9     5     | 7     348   2     | 1     6     348   |
+-------------------+-------------------+-------------------+

ALS-XZ: (8=9)r1c7-(9=368)r124c5 -> r4c7 <> 8 = 4
The rest are singles only.

This ALS-XZ only involves 4 cells. So it's not really harder to spot than a Sue de Coq with 4 cells.
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Jean-Christophe
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." Sherlock Holmes.
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wapati

Joined: 12 Jun 2007
Posts: 622
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Location: Canada

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PostPosted: Mon Jul 07, 2008 9:58 pm    Post subject: Reply with quote

Nice find Jean-Christophe !

I got to the same place as you (doing it on paper) and found a finned swordfish, a different ALS and then two xy-wings.
Your method was sitting there through each of my steps! Embarassed

Code:

+-------------------+-------------------+-------------------+
| 368   5     1     | 2     369   7     | 89    4     3689  |
| 9     36    27    | 8     36    4     | 27    1     5     |
| 3678  2346  2478  | 1     5    #369   | 2789 #378   3689  |
+-------------------+-------------------+-------------------+
| 2     7     9     |#34    368  #368   | 48    5     1     |
| 5     1     3     | 49    7     89    | 6     2     48    |
| 4     8     6     | 5     2     1     | 3     9     7     |
+-------------------+-------------------+-------------------+
| 3678  2346  2478  |#39    1    #389   | 5    #378   489-3 |
| 1     34    478   | 6     3489  5     | 4789 #378   2     |
| 38    9     5     | 7     348   2     | 1     6     348   |
+-------------------+-------------------+-------------------+

+-------------------+-------------------+-------------------+
| 368   5     1     | 2     369   7     | 89    4     3689  |
| 9     36    27    | 8     36    4     | 27    1     5     |
| 3678  2346  2478  | 1     5     369   | 2789  378   3689  |
+-------------------+-------------------+-------------------+
| 2     7     9     | 34    368   368   | 48    5     1     |
| 5     1     3     | 49    7     89    | 6     2    #48    |
| 4     8     6     | 5     2     1     | 3     9     7     |
+-------------------+-------------------+-------------------+
| 3678  2346  2478  | 39    1     389   | 5    @378   49-8  |
| 1     34    478   | 6     3489  5     | 4789 @378   2     |
| 38    9     5     | 7     348   2     | 1     6    @348   |
+-------------------+-------------------+-------------------+

+-------------------+-------------------+-------------------+
| 368   5     1     | 2     369   7     | 89    4     3689  |
| 9     36    27    | 8     36    4     | 27    1     5     |
| 3678  2346  2478  | 1     5     369   | 2789  378   3689  |
+-------------------+-------------------+-------------------+
| 2     7     9     | 34    368   368   | 48    5     1     |
| 5     1     3     | 49    7    *89    | 6     2    *48    |
| 4     8     6     | 5     2     1     | 3     9     7     |
+-------------------+-------------------+-------------------+
| 3678  2346  2478  | 39    1     38-9  | 5     378  *49    |
| 1     34    478   | 6     3489  5     | 4789  378   2     |
| 38    9     5     | 7     348   2     | 1     6     348   |
+-------------------+-------------------+-------------------+

+-------------------+-------------------+-------------------+
| 368   5     1     | 2     369   7     | 89    4     3689  |
| 9     36    27    | 8     36    4     | 27    1     5     |
| 3678  2346  2478  | 1     5     369   | 2789  378   3689  |
+-------------------+-------------------+-------------------+
| 2     7     9     | 34    368   368   | 48    5     1     |
| 5     1     3     | 4-9   7    *89    | 6     2     48    |
| 4     8     6     | 5     2     1     | 3     9     7     |
+-------------------+-------------------+-------------------+
| 3678  2346  2478  |*39    1    *38    | 5     378   49    |
| 1     34    478   | 6     3489  5     | 4789  378   2     |
| 38    9     5     | 7     348   2     | 1     6     348   |
+-------------------+-------------------+-------------------+
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wapati

Joined: 12 Jun 2007
Posts: 622
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Location: Canada

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PostPosted: Tue Jul 08, 2008 9:07 am    Post subject: Reply with quote

Smalls including W-Wing.

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

Joined: 12 Jun 2007
Posts: 622
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Location: Canada

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PostPosted: Wed Jul 09, 2008 9:12 am    Post subject: Reply with quote

Swordfish, finned swordfish.
There are several Kites that are hard to avoid.
W-wings can avoid the swordfish.

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

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Posts: 622
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Location: Canada

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PostPosted: Thu Jul 10, 2008 9:13 am    Post subject: Reply with quote

Swordfish, finned swordfish, sue de coq.

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

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Posts: 622
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PostPosted: Fri Jul 11, 2008 9:07 am    Post subject: Reply with quote

Finned and sashimi swords.

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

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Posts: 622
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PostPosted: Sat Jul 12, 2008 12:26 pm    Post subject: Reply with quote

URs, Sword, finned sword, and sashimi sword.

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

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Posts: 622
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Location: Canada

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PostPosted: Sat Jul 12, 2008 4:49 pm    Post subject: Reply with quote

JSudoku generated. I am having great fun with this!

Bonus puzzle. This one needs W-wing/ M-wing/ 2 ALS patterns, where "/" means "or". Smile

Sashimi sword, 2 skyscrapers, maybe the x-wing and one of the above.

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


Here is an example of an M-wing, close to a W-wing and xy-wing in terms of spotting the pattern. The cells marked "*" are strongly linked on 1. The cells marked "@" are strongly linked on 2.
Code:
+-------------------------------------+
|  .  *12  .  | -2  .  .  |  .  .  .  |
|  .    .  .  |  .  .  .  |  .  .  .  |
|  .    .  .  |  .  .  .  |  .  .  .  |
|-------------+-----------+-----------|
|  .  *13  .  |  .  .  .  |  .  .  .  |
|*12@   .  .  | 26@ .  .  |  .  .  .  |
|  .    .  .  |  .  .  .  |  .  .  .  |
|-------------+-----------+-----------|
|  .    .  .  |  .  .  .  |  .  .  .  |
|  .    .  .  |  .  .  .  |  .  .  .  |
|  .    .  .  |  .  .  .  |  .  .  .  |
+-------------------------------------+
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wapati

Joined: 12 Jun 2007
Posts: 622
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Location: Canada

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PostPosted: Sun Jul 13, 2008 8:21 am    Post subject: Reply with quote

Small patterns.

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


Bonus puzzle.

UR type 6 (twice), UR and 3 W-wings.

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

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Location: Canada

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PostPosted: Sun Jul 13, 2008 10:55 pm    Post subject: Reply with quote

Incredibly easy puzzle. W-wing by-passes 3 sashimi swordfish and a jellyfish.
Only hard technique is W-wing/semi-remote pair/y-wing styles.
There is an nearly worthless W-wing also available.
Use the one with 3 eliminations, not one.

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

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PostPosted: Mon Jul 14, 2008 7:28 am    Post subject: Reply with quote

Sword, finned sword, sashimi sword, BUG.

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

Joined: 12 Jun 2007
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PostPosted: Tue Jul 15, 2008 10:06 am    Post subject: Reply with quote

Hidden UR, UR, BUG.
W-wing available.

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

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PostPosted: Wed Jul 16, 2008 3:21 pm    Post subject: Reply with quote

Swordfish, hidden UR.

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

Here is a hidden UR.
"#" marks strong links on A.

+-----------------------------------------+
| #AB   . #ABD    |  .  .  .  |  .  .  .  |
|  .    .  .      |  .  .  .  |  .  .  .  |
|  .    .  .      |  .  .  .  |  .  .  .  |
|-----------------+-----------+-----------|
|  .    .  .      |  .  .  .  |  .  .  .  |
|  .    .  .      |  .  .  .  |  .  .  .  |
| #ABC  .  AEF-B  |  .  .  .  |  .  .  .  |
|-----------------+-----------+-----------|
|  .    .  .      |  .  .  .  |  .  .  .  |
|  .    .  .      |  .  .  .  |  .  .  .  |
|  .    .  .      |  .  .  .  |  .  .  .  |
+-----------------------------------------+

Here is UR practice.  There are about 6 including a hidden UR.

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

Joined: 12 Jun 2007
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PostPosted: Thu Jul 17, 2008 2:41 pm    Post subject: Reply with quote

Sword, finned sword, sashimi sword, UR.
W-wing available.

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

Joined: 09 Mar 2007
Posts: 22
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PostPosted: Thu Jul 17, 2008 2:54 pm    Post subject: Reply with quote

Wapati said:
Quote:
Here is UR practice. There are about 6 including a hidden UR.

Thanks for the excercise. Even though I am still looking for all of them I have learned a lot.

dan
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