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April 16 VH

 
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prakash



Joined: 02 Jan 2008
Posts: 67
Location: New Jersey, USA

PostPosted: Wed Apr 16, 2008 12:20 am    Post subject: April 16 VH Reply with quote

I thought this would be a one trick wonder. After spotting the first xy-wing (24-47-27) I started plowing through assuming I was done. Surprise! There was the second xy waiting for me (39-36-69). On the whole a good one.
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storm_norm



Joined: 18 Oct 2007
Posts: 1741

PostPosted: Wed Apr 16, 2008 12:35 am    Post subject: Reply with quote

Code:
2      368    58     | 1      469    346    | 7      389    359
13689  1368   7      | 2      5      36     | 4      1389   139
139    4      15     | 37     79     8      | 6      1239   12359
------------------------------------------------------------------
47     9      3      | 6      1      5      | 2      47     8
1678   1678   18     | 4      78     2      | 5      39     39
5      278    24     | 78     3      9      | 1      6      47
------------------------------------------------------------------
1348   12378  24     | 9      468    346    | 38     5      27
38     358    6      | 358    2      7      | 9      14     14
3478   23578  9      | 358    48     1      | 38     27     6



those xy-wings for sure the easiest route...
just for kicks, there is a type 3 UR present in the grid
the first xy-wing opens up a w-wing on {3,6}
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nataraj



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

PostPosted: Wed Apr 16, 2008 5:41 am    Post subject: Reply with quote

For me, it was the xy-wing 24-47-72, and then a w-wing (39, strong link on 3 in first row).

I thoroughly enjoyed this one.
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andras



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

PostPosted: Wed Apr 16, 2008 7:31 am    Post subject: Reply with quote

Actually the xy on 2,4,7 is all that I needed to break the puzzle (Pivot on R7C9).

It was a little slower to start than Monday's, but a good puzzle all the same.

John

(Edited for reasons of jealousy - my wife subsequently did it in about ten minutes and found no advanced techniques at all. And there are no mistakes in her answer - I checked! Smile )
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cgordon



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

PostPosted: Wed Apr 16, 2008 1:28 pm    Post subject: Reply with quote

I thought this was very difficult. In an effort to impress, I tried looking for something other than wings. I found the Type 3 UR mentioned above - first time I've ever found one - but it did nothing. Ended up having to use two xy-wings <247> and <369>.
I'd bet the farm this cannot be done without advanced techniques. Sorry John, I think you and the missus just got lucky.
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tlanglet



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

PostPosted: Wed Apr 16, 2008 1:40 pm    Post subject: Reply with quote

I found the puzzle very time consuming!

After basics, I initially removed a useless <7> at r7c1 using coloring, then the previously reported Type 3 UR and the two xy-wings, but I seemed to make only small progress with each trick and had to essentially start the entire puzzle all over again.

Ted
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nataraj



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

PostPosted: Wed Apr 16, 2008 4:38 pm    Post subject: Reply with quote

cgordon wrote:
I'd bet the farm this cannot be done without advanced techniques. Sorry John, I think you and the missus just got lucky.


Wouldn't bet the farm, but I concur. After the xy-wing and some cleanup, this is where advanced techniques are needed a second time:

Code:

+--------------------------+--------------------------+--------------------------+
| 2       36      8        | 1       69      4        | 7       39      5        |
| 369     1       7        | 2       5       36       | 4       8       39       |
| 39      4       5        | 37      79      8        | 6       1       2        |
+--------------------------+--------------------------+--------------------------+
| 4       9       3        | 6       1       5        | 2       7       8        |
| 678     678     1        | 4       78      2        | 5       39      39       |
| 5       78      2        | 78      3       9        | 1       6       4        |
+--------------------------+--------------------------+--------------------------+
| 1       2       4        | 9       68      36       | 38      5       7        |
| 38      358     6        | 358     2       7        | 9       4       1        |
| 378     3578    9        | 358     4       1        | 38      2       6        |
+--------------------------+--------------------------+--------------------------+

play online
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storm_norm



Joined: 18 Oct 2007
Posts: 1741

PostPosted: Wed Apr 16, 2008 5:54 pm    Post subject: Reply with quote

tlanglet wrote:
I found the puzzle very time consuming!

After basics, I initially removed a useless <7> at r7c1 using coloring, then the previously reported Type 3 UR and the two xy-wings, but I seemed to make only small progress with each trick and had to essentially start the entire puzzle all over again.

Ted


I feel ya, I have to look away for a few minutes just to get my eyes back in my head. concentrating on removing the candidates eliminated by the basic moves is time consuming. but its all worth it when you find that advanced move on the way.
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Dart45



Joined: 16 Apr 2008
Posts: 17
Location: Canada

PostPosted: Wed Apr 16, 2008 8:22 pm    Post subject: Reply with quote

Hello all ... New to this site, but been solving the daily puzzles regularly. I never figured out what wings and all those other tricks of the trade were, but tried solving each day's puzzle as it came, without "pencil" marks or anything else. Just one square at a time! The Easy and Medium levels are never a problem, the Hard ones get me every once in a while, and the Very Hard ones are always a challenge - but most satisfying. Todays was no different - a very pleasant and satisfying challenge to solve outright.
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