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10 June

 
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kragzy



Joined: 01 May 2007
Posts: 112
Location: Australia

PostPosted: Mon Jun 09, 2008 11:55 pm    Post subject: 10 June Reply with quote

I normally resist the uniqueness techniques but a UR on 29 became obvious so early in the piece that I could not resist - the puzzle fell apart in a couple of minutes.

I then did it a second time ignoring the UR and using my normal approach - ended up needing an XYZ wing. Took much longer the second time around.
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Marty R.



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

PostPosted: Tue Jun 10, 2008 1:10 am    Post subject: Reply with quote

I just did it once and used the UR, consistent with my habit of taking the path of least resistance.
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nataraj



Joined: 03 Aug 2007
Posts: 1048
Location: near Vienna, Austria

PostPosted: Tue Jun 10, 2008 6:14 am    Post subject: Reply with quote

I resisted the UR temptation (consistent with my habit of prolonging the pleasure Smile ) and used an x-wing which opened an xyz-wing.

Hint:

The x-wing (3) in rows 5 and 9 removes 3 from c2c8 and r4c2, setting r2c8=1 and r4c2=1.

Now with the 1 gone from r4c1, there is an xyz-wing ( 3,7,8 ) in box 4 and col 3 which removes 7 from r6c3. Thus r6c4=7 and the puzzle falls apart.


Code:

+--------------------------+--------------------------+--------------------------+
| 4       6       2        | 8       3       1        | 5       7       9        |
| 5       8       9        | 26      7       4        | 1236    13      236      |
| 3       7       1        | 9       5       26       | 246     8       246      |
+--------------------------+--------------------------+--------------------------+
| 178     13      378      | 5       48      67       | 2346    9       2346     |
| 6       35      4        | 1       29      29       | 7       35      8        |
| 9       2       578      | 67      48      3        | 146     145     46       |
+--------------------------+--------------------------+--------------------------+
| 27      9       37       | 247     1       8        | 34      6       5        |
| 78      4       578      | 3       6       57       | 9       2       1        |
| 12      135     6        | 24      29      259      | 8       34      7        |
+--------------------------+--------------------------+--------------------------+
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andras



Joined: 31 Oct 2007
Posts: 56
Location: Mid Wales

PostPosted: Tue Jun 10, 2008 6:39 am    Post subject: Reply with quote

I didn't see the x-wing, so went for the UR instead.

Easy, but satisfying!

John
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Johan



Joined: 25 Jun 2007
Posts: 206
Location: Bornem Belgium

PostPosted: Tue Jun 10, 2008 10:13 am    Post subject: Reply with quote

Another UR solution is the 78 UR* in R48C13, which pins <5> in R5C2, all three digits marked (+) in the 78 UR are the possible solutions for avoiding the 78
deadly pattern, all three results in R5C2=5, which solves the puzzle.

Code:
+-------------------------+-------------------------+-------------------------+
| 4         6       2     | 8          3       1    | 5         7       9     |
| 5         8       9     | 26         7       4    | 1236      13      236   |
| 3         7       1     | 9          5       26   | 246       8       246   |
+-------------------------+-------------------------+-------------------------+
|*78+1      13     *78+3  | 5          48      67   | 2346      9       2346  |
| 6         3=5     4     | 1          29      29   | 7         35      8     |
| 9         2       578   | 67         48      3    | 146       145     46    |
+-------------------------+-------------------------+-------------------------+
| 27        9       37    | 247        1       8    | 34        6       5     |
|*78        4      *78+5  | 3          6       57   | 9         2       1     |
| 12        135     6     | 24         29      259  | 8         34      7     |
+-------------------------+-------------------------+-------------------------+
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cgordon



Joined: 04 May 2007
Posts: 769
Location: ontario, canada

PostPosted: Tue Jun 10, 2008 11:23 am    Post subject: Reply with quote

There are x wings for <3> and <7> which exposed the UR on <78>. But I concede the straightforward route is the UR on <29>.
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storm_norm



Joined: 18 Oct 2007
Posts: 1741

PostPosted: Wed Jun 11, 2008 12:53 am    Post subject: Reply with quote

I like the UR here, especially if you use the draw/play, you need to take care of some box line stuff first, then it just all falls into place.
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