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Earl
Joined: 30 May 2007 Posts: 677 Location: Victoria, KS
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Posted: Mon May 11, 2009 2:19 am Post subject: May 11 VH |
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This one offers alternate routes.
Solution: x-wing (3), then xy-wing (269); or an xy-chain beginning at R8C2 to R4C6, extended to R3C5 eliminates the <6> in R3C2 for a single step solution.
Early Earl |
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Marty R.
Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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Posted: Mon May 11, 2009 4:16 am Post subject: |
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I used what I'll call a 1-1/2 step solution.
Quote: | XY-Wing on 239 and then a pincer transport |
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crunched
Joined: 05 Feb 2008 Posts: 168
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Posted: Mon May 11, 2009 5:37 am Post subject: |
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I think below shows the grid after basics are removed.
Code: |
+----------+-------------+----------+
| 5 4 69 | 169 3 169 | 2 7 8 |
| 8 2 39 | 7 49 459 | 1 345 6 |
| 1 36 7 | 256 246 8 | 35 345 9 |
+----------+-------------+----------+
| 2 7 5 | 8 69 69 | 4 1 3 |
| 6 1 8 | 23 24 234 | 59 59 7 |
| 3 9 4 | 15 7 15 | 8 6 2 |
+----------+-------------+----------+
| 7 5 23 | 4 8 29 | 6 39 1 |
| 4 36 236 | 129 129 7 | 39 8 5 |
| 9 8 1 | 36 5 36 | 7 2 4 |
+----------+-------------+----------+
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Play this puzzle online at the Daily Sudoku site
Last edited by crunched on Mon May 11, 2009 5:56 am; edited 1 time in total |
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crunched
Joined: 05 Feb 2008 Posts: 168
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Posted: Mon May 11, 2009 5:50 am Post subject: |
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I also found an x wing on 1s (rows 1 & 6). That opened up a 239 xy wing. But I did not see the xy wing that Earl found. Nor did I solve the puzzle. LOL
Marty R. wrote: | I used what I'll call a 1-1/2 step solution.
Quote: | XY-Wing on 239 and then a pincer transport |
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George Woods
Joined: 28 Mar 2006 Posts: 304 Location: Dorset UK
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Posted: Mon May 11, 2009 9:22 am Post subject: a not v elegant solution! |
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Using the grid given by crunched , I found the XY wing(239) that eliminates the 9 from r2c6. But so What?. Looked hard at the 45 at r2c6 and realised that a 4 kills the 9 at r1c4so r8c4 is9, and a 5 at releases the triplet 236 in col 4 that makes r8c4 9. So r8c4 is 9. Now look again and see that the XY wing wasn't needed for this logic . Use the ALS? set 36 23 and 256 in col 4 . If r3c4 is not 5 then r8c4 is 9, and if it is 5 the the 49 pair in Box2 mean that r8c4 is 9.
So having done all that I went to draw/play and used the hints to see how the "official" solution went- Wow a 9 at r8c4! So something close to my barbaric solution is the "official" one! |
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arkietech
Joined: 31 Jul 2008 Posts: 1834 Location: Northwest Arkansas USA
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Posted: Mon May 11, 2009 12:06 pm Post subject: |
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Needed two steps: Quote: | x-wing 3
xy-wing 269 |
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tlanglet
Joined: 17 Oct 2007 Posts: 2468 Location: Northern California Foothills
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Posted: Mon May 11, 2009 1:57 pm Post subject: |
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Marty R. wrote: | I used what I'll call a 1-1/2 step solution.
Quote: | XY-Wing on 239 and then a pincer transport |
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Marty, I like your new definition! I also solved the puzzle in 1-1/2 steps but used a pincer pseudo-cell. Should my move be called a 1-1/2 + 1/4 = 1-3/4?
xy-wing 369 with pivot 36 in r3c2 and pseudo-cell 69 in row8; transport 9 r8c7 to r1c4 via r8c4 to complete the puzzle.
Ted |
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Ema Nymton
Joined: 17 Apr 2009 Posts: 89
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Posted: Mon May 11, 2009 5:56 pm Post subject: Re: a not v elegant solution! |
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The recent spate of VH Sudoku seem to be exercises in minutiae.
George Woods wrote: | Using the grid given by crunched , I found the XY wing(239) that eliminates the 9 from r2c6. But so What?. Looked hard at the 45 at r2c6 and realised that a 4 kills the 9 at r1c4so r8c4 is9, and a 5 at releases the triplet 236 in col 4 that makes r8c4 9. So r8c4 is 9. Now look again and see that the XY wing wasn't needed for this logic . Use the ALS? set 36 23 and 256 in col 4 . If r3c4 is not 5 then r8c4 is 9, and if it is 5 the the 49 pair in Box2 mean that r8c4 is 9.
So having done all that I went to draw/play and used the hints to see how the "official" solution went- Wow a 9 at r8c4! So something close to my barbaric solution is the "official" one! |
Is this not a fancy way of saying you guessed? ...
Much of the bragging going on here seems to be being done in an absence of reason/logic. As posted, after being crunched,
The basic puzzle has no visible "239" in and cell.
The basic puzzle has no visible triplet 236 in col 4
I am sorry for raining on any one's parade. I have not solved this one and am frustrated.
~@:o?
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Kdelle
Joined: 20 Mar 2008 Posts: 59 Location: Hudson, NH
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Posted: Mon May 11, 2009 7:10 pm Post subject: |
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Never mind......Brain cramp! |
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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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Posted: Mon May 11, 2009 7:22 pm Post subject: |
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George Woods wrote: Quote: | Use the ALS? set 36 23 and 256 in col 4 . If r3c4 is not 5 then r8c4 is 9, and if it is 5 the the 49 pair in Box2 mean that r8c4 is 9. |
George,
I like your logic.
can I assume that you found the hidden single 1 at r8c5 which makes r8c4 {2,9}?
if this is the case then, if you don't mind, I can translate into a chain.
Code: | .---------------.---------------.---------------.
| 5 4 69 |16-9 3 169 | 2 7 8 |
| 8 2 39 | 7 *49 *459 | 1 345 6 |
| 1 36 7 |*256 246 8 | 35 345 9 |
:---------------+---------------+---------------:
| 2 7 5 | 8 69 69 | 4 1 3 |
| 6 1 8 |*23 24 234 | 59 59 7 |
| 3 9 4 | 15 7 15 | 8 6 2 |
:---------------+---------------+---------------:
| 7 5 23 | 4 8 29 | 6 39 1 |
| 4 36 236 |*29 1 7 | 39 8 5 |
| 9 8 1 |*36 5 36 | 7 2 4 |
'---------------'---------------'---------------' |
np = naked pair
nt = naked tripe
np(49)r2c56 = (5)r2c6 - (5)r3c4 = nt(236)r359c4 - (2)r8c4 = (9)r8c4; r1c4 <> 9 |
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Marty R.
Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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Posted: Mon May 11, 2009 9:14 pm Post subject: |
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Quote: | Much of the bragging going on here seems to be being done in an absence of reason/logic. As posted, after being crunched,
The basic puzzle has no visible "239" in and cell.
The basic puzzle has no visible triplet 236 in col 4
I am sorry for raining on any one's parade. I have not solved this one and am frustrated. |
Ema,
If you are referring to my and other references to a 239 XY-Wing, it is indeed present in Crunched's grid.
The 239 designation does not mean a cell with those three numbers. It is a standard method of describing an XY-Wing that consists of three cells, 23-29-39. In the grid above it can be found in r7c3, r7c6 and r2c3. The pincers of 9 remove the 9 from r2c6, after which the 9 from r2c3 can be transported to r4c5 (via r2c5) and the new pincers remove the 9 from r4c6. |
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swando
Joined: 09 Mar 2009 Posts: 17 Location: Surrey, BC. Canada
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Posted: Tue May 12, 2009 7:42 am Post subject: |
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This were I got with the basics and then used a 269 to eliminate the 9 in R 1 C4 and that did it.
[code]
+---------+-------------+----------+
| 5 4 69 | 169 3 169 | 2 7 8 |
| 8 2 39 | 7 49 459 | 1 345 6 |
| 1 36 7 | 256 246 8 | 35 45 9 |
+---------+-------------+----------+
| 2 7 5 | 8 69 69 | 4 1 3 |
| 6 1 8 | 23 24 234 | 59 59 7 |
| 3 9 4 | 15 7 15 | 8 6 2 |
+---------+-------------+----------+
| 7 5 23 | 4 8 29 | 6 39 1 |
| 4 36 26 | 29 1 7 | 39 8 5 |
| 9 8 1 | 36 5 36 | 7 2 4 |
+---------+-------------+----------+ |
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Ema Nymton
Joined: 17 Apr 2009 Posts: 89
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Posted: Tue May 12, 2009 12:00 pm Post subject: |
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Thank you for the help. It is very helpful.
Marty R. wrote: | Quote: | Much of the bragging going on here seems to be being done in an absence of reason/logic. As posted, after being crunched,
The basic puzzle has no visible "239" in and cell.
The basic puzzle has no visible triplet 236 in col 4
I am sorry for raining on any one's parade. I have not solved this one and am frustrated. |
Ema,
If you are referring to my and other references to a 239 XY-Wing, it is indeed present in Crunched's grid.
The 239 designation does not mean a cell with those three numbers. It is a standard method of describing an XY-Wing that consists of three cells, 23-29-39. In the grid above it can be found in r7c3, r7c6 and r2c3. The pincers of 9 remove the 9 from r2c6, after which the 9 from r2c3 can be transported to r4c5 (via r2c5) and the new pincers remove the 9 from r4c6. |
~@:o?
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