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April 18 VH - Wing It

 
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prakash



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

PostPosted: Fri Apr 18, 2008 12:35 am    Post subject: April 18 VH - Wing It Reply with quote

For me, this one required a lot of advanced techniques. An X-Wing in 8, an XY-Wing 46-45-56, An X-Wing on 7 and an XYZ wing 46-467-47. I am sure there is a better way. Not really understanding ERs, I did not try to find any.
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Marty R.



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

PostPosted: Fri Apr 18, 2008 5:08 am    Post subject: Reply with quote

I don't know about ERs in this one, I didn't look for them. But the X-Wing on 7 and a W-Wing on 47 did the trick.
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storm_norm



Joined: 18 Oct 2007
Posts: 1741

PostPosted: Fri Apr 18, 2008 6:03 am    Post subject: Reply with quote

x-wing on 7
xy-wing 4,5,6
xyz-wing 4,6,7 in box 5
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Johan



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

PostPosted: Fri Apr 18, 2008 7:52 am    Post subject: Reply with quote

I found a 4-cell xy-chain (64-47-75-56) with pincer ends at R6C4(A) and R5C8(D), which eliminates <6> in R5C4, that collapses the whole puzzle.

Code:
+-------------------------+-------------------------+-------------------------+
| 3578      4       357   | 1         39      2     | 568       567     3569  |
| 378       1       9     | 5         6       347   | 48        2       34    |
| 2         6       357   | 47 B      389     3478  | 1       C 57      3459  |
+-------------------------+-------------------------+-------------------------+
| 367       9       8     | 2         35      37    | 456       1       456   |
| 1         37      3467  | 4-[6]7    358     3478  | 9       D 56      2     |
| 46        5       2     | 46 A      1       9     | 7         3       8     |
+-------------------------+-------------------------+-------------------------+
| 9         8       56    | 3         2       1     | 56        4       7     |
| 45        2       145   | 8         7       6     | 3         9       15    |
| 367       37      1367  | 9         4       5     | 2         8       16    |
+-------------------------+-------------------------+-------------------------+
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sdq_pete



Joined: 30 Apr 2007
Posts: 119
Location: Rotterdam, NL

PostPosted: Fri Apr 18, 2008 12:54 pm    Post subject: Reply with quote

storm_norm wrote:
x-wing on 7
xy-wing 4,5,6
xyz-wing 4,6,7 in box 5

ditto. Not sure the X-wing on 7 was really necessary.

Peter
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tlanglet



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

PostPosted: Fri Apr 18, 2008 1:19 pm    Post subject: Reply with quote

sdq_pete wrote:

Not sure the X-wing on 7 was really necessary.

Peter


Peter,

I used the x-wing to remove the <7> at r1c9 to make that cell a <3>. Then, r1c9=<3>=>r9c2=7=>r5c2=3 thereby eliminating the <3> at r5c3 which is needed for the <467> xyz-wing in box 5.

Ted


Last edited by tlanglet on Fri Apr 18, 2008 9:26 pm; edited 1 time in total
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Stanley P



Joined: 27 Feb 2008
Posts: 20
Location: Tennessee, USA

PostPosted: Fri Apr 18, 2008 1:47 pm    Post subject: Reply with quote

I did the wing thing on this one successfully. From an efficiency standpoint it appears that the xy-chain is quite a bit better. I usually look for xy-chains after getting frustrated trying to find wings. Maybe I should reverse the order and look for chains first.
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cgordon



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

PostPosted: Fri Apr 18, 2008 6:32 pm    Post subject: Reply with quote

OK - I need serious help. I found an x-wing, an xy-wing and an xyz wing.
I also found two ERs for <5> and <7>. That's more than the rest of you put together - and yet I can't get past this point. If I stare at it any longer I could damage something. I reckon I'm missing something (maybe the left side of the brain!)


Code:
            
+----------+-----------+-----------+   
|3578 4 357| 1  39  2  |68 567 3569|   
|378  1  9 | 5  6  347 |48  2   34 |   
| 2   6 357|47 389 348 | 1 57  3459|   
+-------+--------------+-----------+   
|367  9  8 | 2  35  37 |456  1  456|   
| 1  37 347|467 358 348| 9  56   2 |   
|46   5  2 |46   1   9 | 7   3   8 |   
+----------+-----------+-----------+   
| 9   8  56| 3   2   1 |56   4   7 |   
|45   2 145| 8   7   6 | 3   9  15 |   
|37  37  16| 9   4   5 | 2   8  16 |
+----------+-----------+-----------+
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Marty R.



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

PostPosted: Fri Apr 18, 2008 7:33 pm    Post subject: Reply with quote

Check out the X-Wing on 7 in rows 2 and 4.

(Edited to correct "rows 2 and 5" to "rows 2 and 4").


Last edited by Marty R. on Sat Apr 19, 2008 12:50 am; edited 1 time in total
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cgordon



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

PostPosted: Fri Apr 18, 2008 8:05 pm    Post subject: Reply with quote

Quote:
Check out the X-Wing on 7 in rows 2 and 5.

I don't believe it! I was staring at this thing for at least an hour. Also I have often thought x-wings are so easy to spot, they don't deserve to be in the Very Hard category. Can't win 'em all eh!
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cgordon



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

PostPosted: Fri Apr 18, 2008 8:40 pm    Post subject: Reply with quote

'ang about !! My xyz wing is <347> from box2. Using the x-wing on 7s on my grid, I don't see any <467> xyz in Box 5 mentioned above. Maybe it's not me!
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tlanglet



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

PostPosted: Fri Apr 18, 2008 9:24 pm    Post subject: Reply with quote

cgordon wrote:
'ang about !! My xyz wing is <347> from box2. Using the x-wing on 7s on my grid, I don't see any <467> xyz in Box 5 mentioned above. Maybe it's not me!


As I indicated in my earlier message, I needed the x-wing on <7> to "create" the <467> xyz-wing. xyz <467> is in r5c4 and xz <46> is in r6c4 as given in the code you posted. yz <47> is in r5c3 once the <3> is removed from that cell via the x-wing elimination of <7> in r9c1 and the basic eliminations that result from it.

Ted
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cgordon



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

PostPosted: Fri Apr 18, 2008 9:56 pm    Post subject: Reply with quote

Thank you Ted. Based on my struggles with this one, I think they should give me a good meal and put me down.
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crunched



Joined: 05 Feb 2008
Posts: 168

PostPosted: Fri Apr 18, 2008 10:51 pm    Post subject: Reply with quote

Marty R. wrote:
Check out the X-Wing on 7 in rows 2 and 5.


I hope you mean rows 2 & 4 (not rows 2 and 5), which would take out some 7s in column 1? Otherwise, I am lost.
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Marty R.



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

PostPosted: Sat Apr 19, 2008 12:48 am    Post subject: Reply with quote

crunched wrote:
Marty R. wrote:
Check out the X-Wing on 7 in rows 2 and 5.


I hope you mean rows 2 & 4 (not rows 2 and 5), which would take out some 7s in column 1? Otherwise, I am lost.

Yes, sorry for the typo.
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Glassman



Joined: 21 Oct 2005
Posts: 50
Location: England

PostPosted: Sat Apr 26, 2008 10:18 pm    Post subject: Reply with quote

What you all seem to have missed is the jellyfish (order 4 x-wing) on 7s not that it solves the puzzle more quickly, but that it is such a rarity in order 9 puzzles. It is the first order 9 jellyfish I have found and I felt like breaking out the champers!

In combination with the 456 xy-wing, the 7s jellyfish quickly resolves c2.
Thank you, Sam.



Glassman Cool
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