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crunched
Joined: 05 Feb 2008 Posts: 168
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Posted: Tue May 26, 2009 4:50 am Post subject: May 26, VH |
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Where is the Earlster?
Here is the grid after basics. It proved to be a one-stepper for me. I did the whole puzzle in about 10 minutes. That means the wizards here probably solved it in about 30 seconds.
Code: |
+---------+-----------+-----------+
| 68 3 2 | 14 9 17 | 5 48 4678 |
| 1 58 4 | 6 57 2 | 9 3 78 |
| 56 9 7 | 45 8 3 | 2 1 46 |
+---------+-----------+-----------+
| 58 58 9 | 7 1 6 | 4 2 3 |
| 3 2 1 | 458 45 48 | 6 7 9 |
| 4 7 6 | 3 2 9 | 8 5 1 |
+---------+-----------+-----------+
| 9 1 3 | 2 6 48 | 7 48 5 |
| 7 4 8 | 9 3 5 | 1 6 2 |
| 2 6 5 | 148 47 17 | 3 9 48 |
+---------+-----------+-----------+
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Play this puzzle online at the Daily Sudoku site |
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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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Posted: Tue May 26, 2009 5:46 am Post subject: |
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crunched,
you have a pointing pair of 4's in column 4 in box 2. |
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arkietech
Joined: 31 Jul 2008 Posts: 1834 Location: Northwest Arkansas USA
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Posted: Tue May 26, 2009 11:54 am Post subject: |
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One step: Quote: | a 468 xy-wing did it for me
| An easy one. |
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giadich
Joined: 15 May 2009 Posts: 3
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Posted: Tue May 26, 2009 4:00 pm Post subject: |
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The HARD rated puzzle on 5-24 is much harder than this one 5-26! |
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Clement
Joined: 24 Apr 2006 Posts: 1111 Location: Dar es Salaam Tanzania
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Posted: Tue May 26, 2009 6:52 pm Post subject: Daily Sudoku: Tue 26-May-2009 VH |
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BUG 1 Solves the puzzle. |
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Wendy W
Joined: 04 Feb 2008 Posts: 144
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Posted: Tue May 26, 2009 11:27 pm Post subject: |
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Really easy. I thought I'd make a mistake, it was falling apart so quickly (NO -- how could that be). After basics the first XY-wing solved the whole thing. |
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crunched
Joined: 05 Feb 2008 Posts: 168
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Posted: Tue May 26, 2009 11:57 pm Post subject: |
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storm_norm wrote: | crunched,
you have a pointing pair of 4's in column 4 in box 2. |
Yep, you are correct. Below is the grid after the "pointing pair" takes out a coupla 4s:
Wendy, I had the same good fortune, that the 1st xy wing solved the puzzle. However, note how many xy-wings are in this puzzle: 4-5-8, 1-4-8, 4-5-7 & 4-6-8. Those other than the 4-6-8 are not worth anything from what I can find. Usually my luck is to have the find the last xy-wing to do any good.
Code: |
+---------+----------+-----------+
| 68 3 2 | 14 9 17 | 5 48 4678 |
| 1 58 4 | 6 57 2 | 9 3 78 |
| 56 9 7 | 45 8 3 | 2 1 46 |
+---------+----------+-----------+
| 58 58 9 | 7 1 6 | 4 2 3 |
| 3 2 1 | 58 45 48 | 6 7 9 |
| 4 7 6 | 3 2 9 | 8 5 1 |
+---------+----------+-----------+
| 9 1 3 | 2 6 48 | 7 48 5 |
| 7 4 8 | 9 3 5 | 1 6 2 |
| 2 6 5 | 18 47 17 | 3 9 48 |
+---------+----------+-----------+
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Play this puzzle online at the Daily Sudoku site |
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cgordon
Joined: 04 May 2007 Posts: 769 Location: ontario, canada
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Posted: Wed May 27, 2009 1:57 pm Post subject: |
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I saw a different xy wing using <478>. But I don't see Clement's Bug+1 with all those triples still remaining. |
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Marty R.
Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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Posted: Wed May 27, 2009 3:40 pm Post subject: |
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cgordon wrote: | I saw a different xy wing using <478>. But I don't see Clement's Bug+1 with all those triples still remaining. |
The original posted grid had locked 4s which made eliminations. Look at Crunched's grid right above your post. |
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cgordon
Joined: 04 May 2007 Posts: 769 Location: ontario, canada
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Posted: Wed May 27, 2009 4:17 pm Post subject: |
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Yes - I missed that - but still don't see how to use a Bug+1 with a quad left. |
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Marty R.
Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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Posted: Wed May 27, 2009 4:42 pm Post subject: |
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cgordon wrote: | Yes - I missed that - but still don't see how to use a Bug+1 with a quad left. |
Well, I'm not 100% sure of the logic, but someone will let me know if it's wrong. If you remove the 4 and 8 from the quad cell you'd be left with the BUG pattern. Thus it needs to be 4 or 8 to kill the BUG. |
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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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Posted: Wed May 27, 2009 6:43 pm Post subject: |
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Marty R. wrote: | cgordon wrote: | Yes - I missed that - but still don't see how to use a Bug+1 with a quad left. |
Well, I'm not 100% sure of the logic, but someone will let me know if it's wrong. If you remove the 4 and 8 from the quad cell you'd be left with the BUG pattern. Thus it needs to be 4 or 8 to kill the BUG. |
Marty,
that is some awesome logic.
r1c9 <> 67 |
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cgordon
Joined: 04 May 2007 Posts: 769 Location: ontario, canada
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Posted: Wed May 27, 2009 7:20 pm Post subject: |
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Quote: | Marty, that is some awesome logic |
I once read that a BUG was an acronym for a Bivalue Universal Grave – which sounds more like something from Shawn of the Dead. I just remember techniques by rote. Thus: if there’s one triple left in the puzzle -say 123, and it sees a 13 and a 23 – shove the no that occurs three times (ie. 3) in place of the triple. Marty’s logic requires too much painful thinking. |
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Wendy W
Joined: 04 Feb 2008 Posts: 144
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Posted: Thu May 28, 2009 12:15 am Post subject: |
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CG, that is the best and most easily understandable explanation of a BUG I've ever seen.
Would you please get a job writing cell phone manuals? |
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Clement
Joined: 24 Apr 2006 Posts: 1111 Location: Dar es Salaam Tanzania
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Posted: Sat May 30, 2009 5:45 pm Post subject: Daily Sudoku: Tue 26-May-2009 VH |
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Storm_norm wrote: Quote: | Marty,
that is some awesome logic |
The 4 in r1c9 is removed by the XY-Wing (148) with pivot(18)r9c4 and that cell(r1c9) remains with three candidates (678). All the remaining cells are bi-value, hence, the BUG pattern |
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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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Posted: Sat May 30, 2009 11:56 pm Post subject: Re: Daily Sudoku: Tue 26-May-2009 VH |
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Clement wrote: | Storm_norm wrote: Quote: | Marty,
that is some awesome logic |
The 4 in r1c9 is removed by the XY-Wing (148) with pivot(18)r9c4 and that cell(r1c9) remains with three candidates (678). All the remaining cells are bi-value, hence, the BUG pattern |
or
because of the BUG either r1c9 is 4 or 8... BUG[(4=8)r1c9]
BUG[(8=4)r1c9] - (4=1)r1c4 - (1=8)r9c4; means r9c9 <> 8 |
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