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xx men's mags

 
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prakash



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

PostPosted: Wed Aug 06, 2008 1:35 am    Post subject: xx men's mags Reply with quote

than this have severely reduced fitness faster rates of cell growth and cell pro- changes in antigenic and cytoadherent
give in to it! Better to give in to a craving and allow yourself 100 extra calories broom handles, and balls of various assimilate inorganic minerals. You can only assimilate
Yeah, sorry for the views with no responses. I tend to stay away from NetBeans, after having used it years ago when it really wasn't all that good. Eclipse is where it's at for me, though I'm sure
gous, leading to the suggestion that the unit, units with D- and L-configurations 590 Chirality in Biology morphology. The fact that cells commonly


Last edited by prakash on Tue Sep 07, 2010 1:59 pm; edited 2 times in total
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storm_norm



Joined: 18 Oct 2007
Posts: 1741

PostPosted: Wed Aug 06, 2008 4:17 am    Post subject: Re: Aug 06 VH Reply with quote

prakash wrote:
Finally a VH. As usual, I used the wings. Also trying Marty's trick to make sure I don't spoil the fun for the others. Still can't figure out how to put the code in keep the color white.

Quote:


X wing on 1 clears up quite a bit.
XY Wing 16-68-18 removes 1 from R3C2
After the basics:
.---------------.---------------.---------------.
| 18 3 5 | 7 2 9 | 4 6 18 |
| 126 4 27 | 16 3 8 | 17 9 5 |
| 168 19 79 | 16 5 4 | 178 2 3 |
:---------------+---------------+---------------:
| 4 26 38 | 25 18 56 | 9 13 7 |
| 5 7 1 | 9 4 3 | 2 8 6 |
| 9 26 38 | 28 7 16 | 5 13 4 |
:---------------+---------------+---------------:
| 7 19 29 | 58 6 15 | 3 4 128 |
| 3 5 6 | 4 18 2 | 18 7 9 |
| 12 8 4 | 3 9 7 | 6 5 12 |
'---------------'---------------'---------------'


I never believed it was cooth to disguise the solutions in white as to not give the solutions away to quickly so that others would find joy in the puzzle without spoiling the fun... I even tried it myself...

totally absurd in my opinion

...Absurdity meter... this falls in about 9.9 Exclamation
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nataraj



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

PostPosted: Wed Aug 06, 2008 6:08 am    Post subject: Reply with quote

Same solution as prakash.

The xy becomes visible only after the x.
Here's the position after basics

Code:

+--------------------------+--------------------------+--------------------------+
| 18      3       5        | 7       2       9        | 4       6       18       |
| 126     4       27       | 16      3       8        | 17      9       5        |
| 168     19      79       | 16      5       4        | 178     2       3        |
+--------------------------+--------------------------+--------------------------+
| 4       26      38       | 25      18      56       | 9       13      7        |
| 5       7       1        | 9       4       3        | 2       8       6        |
| 9       26      38       | 28      7       16       | 5       13      4        |
+--------------------------+--------------------------+--------------------------+
| 7       19      29       | 58      6       15       | 3       4       128      |
| 3       5       6        | 4       18      2        | 18      7       9        |
| 12      8       4        | 3       9       7        | 6       5       12       |
+--------------------------+--------------------------+--------------------------+


As a uniqueness alternative to the wings:

A) consider the potential DP 16 in r23c14.
There is a strong link on 6 in col 1, which means that if any of r23c1 were 1, the other would have to be 6 - which is the deadly pattern (UR type 4)

Therefore neither r2c1 nor r3c1 can be 1.

B) This leaves a BUG+2 situation. In order to avoid the DP, one of r3c7,r7c9 must be 1. That is only possible if r1c9=8.

It is interesting that this last elimination was achieved using a single strong link (1)r3c7=r7c9 created by the BUG+2 argument. Usually (when we look at strong links as two cells in a house containing a given candidate) we need at least two strong plus one weak link to make the elimination.
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Captain Pete



Joined: 09 Jun 2007
Posts: 55
Location: Oley, PA

PostPosted: Wed Aug 06, 2008 12:34 pm    Post subject: A request for tougher puzzles Reply with quote

I an not an "advanced" puzzle solver, but after doing VH puzzles at this site for a year or so, they are no longer much of a challenge. After basics on today's puzzle, one obvious XYZ wing opened up the puzzle to a quick solution. I wonder if the folks running this site couldn't include a "super hard" from time to time, along the lines of the SH Menneske puzzles. Not only would the puzzles be a challenge, the discussion would be helpful to those of us trying to learn advanced techniques.
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wings



Joined: 06 Aug 2008
Posts: 1
Location: HONG KONG

PostPosted: Wed Aug 06, 2008 2:54 pm    Post subject: Re: A request for tougher puzzles Reply with quote

Captain Pete wrote:
I an not an "advanced" puzzle solver, but after doing VH puzzles at this site for a year or so, they are no longer much of a challenge. After basics on today's puzzle, one obvious XYZ wing opened up the puzzle to a quick solution. I wonder if the folks running this site couldn't include a "super hard" from time to time, along the lines of the SH Menneske puzzles. Not only would the puzzles be a challenge, the discussion would be helpful to those of us trying to learn advanced techniques.

would you tell me which XYZ wing, I can not find it
I only find the x wing 1 r1c1 r1c9, r9c1 r9c9
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Marty R.



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

PostPosted: Wed Aug 06, 2008 3:35 pm    Post subject: Reply with quote

The one XYZ-Wing 168-18-16 pivoted in r3c1 was my only move.
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Clement



Joined: 24 Apr 2006
Posts: 1111
Location: Dar es Salaam Tanzania

PostPosted: Wed Aug 06, 2008 6:57 pm    Post subject: Daily Sudoku: Wed 6-Aug-2008 VH Reply with quote

There is a potential deadly pattern on {1/6} in r23c14. 8 cannot be a candidate in r3c7 as it leads to a deadly pattern in r23c14. Therefore, 8 must be in r1c9. This solves the puzzle Smile .
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nataraj



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

PostPosted: Wed Aug 06, 2008 7:10 pm    Post subject: Re: Daily Sudoku: Wed 6-Aug-2008 VH Reply with quote

Clement wrote:
8 cannot be a candidate in r3c7 as it leads to a deadly pattern in r23c14.


How does it do that? Why couldn't r2c1 be 2?

In my grid, if r3c7=8 then r1c9=1, r9c9=2, r9c1=1 and the DP is broken...

Maybe we have different positions?
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Florida Bob



Joined: 25 Jul 2007
Posts: 12

PostPosted: Wed Aug 06, 2008 7:24 pm    Post subject: Reply with quote

I didn't find any wings however I found that if R3C2 is a 1 then you have a bug situation. Place the 9 there and the puzzle solves quickly.
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nataraj



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

PostPosted: Wed Aug 06, 2008 8:03 pm    Post subject: Reply with quote

Florida Bob wrote:
I didn't find any wings however I found that if R3C2 is a 1 then you have a bug situation. Place the 9 there and the puzzle solves quickly.


It so happens that the xyz-wing mentioned by Captain Pete and Marty R. removes exactly that same 1 from r3c2 Smile

and it does so by using the same cells that appear in the contradiction (not a BUG pattern) created by setting r3c2=1:

if r3c2=1 then r3c4=6,r1c1=8 and r3c1 is left without candidates (contradiction)

when looked at from the other side, the xyz wing pattern says that the combination of r1c1,r3c1 and r3c4 means that r3c2 cannot be 1...

So, in a way, Florida Bob, you did find the xyz wing Very Happy
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Clement



Joined: 24 Apr 2006
Posts: 1111
Location: Dar es Salaam Tanzania

PostPosted: Wed Aug 06, 2008 8:23 pm    Post subject: Daily Sudoku: Wed 6-Aug-2008 VH Reply with quote

It goes like this:r3c7=8 leaves {1/6} in r3c1 and r1c9=1, r2c7=7,r2c3=2 leaving {1/6} in r2c1 the deadly pattern.
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nataraj



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

PostPosted: Wed Aug 06, 2008 8:56 pm    Post subject: Reply with quote

I see ... From r1c9=1 we get
a) (by way of c9, r9, c1 and r1; my chain) r3c1=6 and r2c1=2
b) (by way of r1 and r2; Clement's chain) r2c1<>2

So, with or without the uniqueness argument, 1 in r1c9 is toast...
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Asellus



Joined: 05 Jun 2007
Posts: 865
Location: Sonoma County, CA, USA

PostPosted: Wed Aug 06, 2008 9:56 pm    Post subject: Reply with quote

Clement's elimination is an XY Chain that exploits the strong link (2=8) induced in the 16 UR:
UR[(8)r3c1=(2)r2c1] - (2=7)r2c3 - (7=1)r2c7 - (1=8)r1c9; r3c7<>8
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arkietech



Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA

PostPosted: Wed Aug 06, 2008 10:56 pm    Post subject: Reply with quote

A couple of x-wings and a triple got me here:
Code:

 *--------------------------------------------------*
 | 18   3    5    | 7    2    9    | 4    6    18   |
 | 26   4    27   | 16   3    8    | 17   9    5    |
 | 68   19   79   | 16   5    4    | 178  2    3    |
 |----------------+----------------+----------------|
 | 4    26   38   | 25   18   56   | 9    13   7    |
 | 5    7    1    | 9    4    3    | 2    8    6    |
 | 9    26   38   | 28   7    16   | 5    13   4    |
 |----------------+----------------+----------------|
 | 7    19   29   | 58   6    15   | 3    4    28   |
 | 3    5    6    | 4    18   2    | 18   7    9    |
 | 12   8    4    | 3    9    7    | 6    5    12   |
 *--------------------------------------------------*

This leaves an xy-wing or bug+1 to finish.
Being new to the forum -- did I miss something?
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kragzy



Joined: 01 May 2007
Posts: 112
Location: Australia

PostPosted: Thu Aug 07, 2008 2:16 am    Post subject: Reply with quote

I'm with arkitech on this one. Basics led me to the position posted by him and all that I could see was the BUG which solved it quickly. Being a disliker of uniqueness solutions, I looked for a wing but couldn't find any. Obviously didn't check carefully enough.

To save me the effort of re-looking, can you tell where you saw the XY wing please Dan.

Thanks
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kragzy



Joined: 01 May 2007
Posts: 112
Location: Australia

PostPosted: Thu Aug 07, 2008 2:17 am    Post subject: Reply with quote

Oh, and I meant to say, welcome to the forum!

Cheers
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Marty R.



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

PostPosted: Thu Aug 07, 2008 3:35 am    Post subject: Reply with quote

Quote:
To save me the effort of re-looking, can you tell where you saw the XY wing please Dan.


Umm, my name's not Dan, but there's a 68-18-16 XY-Wing pivoted in r3c1, the same cell where the XYZ-Wing was pivoted.
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kragzy



Joined: 01 May 2007
Posts: 112
Location: Australia

PostPosted: Thu Aug 07, 2008 7:02 am    Post subject: Reply with quote

Ah-ha! I knew it would be there somewhere.

Thanks Marty-Dan
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arkietech



Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA

PostPosted: Thu Aug 07, 2008 10:53 am    Post subject: Reply with quote

kragzy said:
Quote:
To save me the effort of re-looking, can you tell where you saw the XY wing please Dan.


Here is the xy-wing I saw:
Code:

 *--------------------------------------------------*
 |*18   3    5    | 7    2    9    | 4    6    18   |
 | 26   4    27   | 16   3    8    | 17   9    5    |
 |*68   9-1  79   |*16   5    4    | 178  2    3    |
 |----------------+----------------+----------------|
 | 4    26   38   | 25   18   56   | 9    13   7    |
 | 5    7    1    | 9    4    3    | 2    8    6    |
 | 9    26   38   | 28   7    16   | 5    13   4    |
 |----------------+----------------+----------------|
 | 7    19   29   | 58   6    15   | 3    4    28   |
 | 3    5    6    | 4    18   2    | 18   7    9    |
 | 12   8    4    | 3    9    7    | 6    5    12   |
 *--------------------------------------------------*


Hope this helps
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kragzy



Joined: 01 May 2007
Posts: 112
Location: Australia

PostPosted: Fri Aug 08, 2008 8:39 am    Post subject: Reply with quote

thanks
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