| View previous topic :: View next topic |
| Author |
Message |
ravel
Joined: 21 Apr 2006
Posts: 536
|
 Posted: Mon Aug 11, 2008 4:09 pm Post subject: VH+ by JPF (game 0045) |
 |
|
| Code: | +-------+-------+-------+
| . . 1 | 2 . . | . . . |
| . 3 . | . . 4 | 5 . . |
| 6 . . | . . . | . 1 . |
+-------+-------+-------+
| 1 . . | 7 . . | . 6 . |
| . . . | . . . | . . . |
| . 4 . | . . 8 | . . 5 |
+-------+-------+-------+
| . 9 . | . . . | . . 4 |
| . . 3 | 6 . . | . 7 . |
| . . . | . . 5 | 8 . . |
+-------+-------+-------+ JPF
|
>>> play online
I forgot to answer a PM question, where these puzzles are from. I find them in the Patterns Game. Puzzles with ratings between 6.9 and 7.2 may be good candidates for a VH+. But they also can be rather hard, so be careful. |
|
| Back to top |
|
 |
nataraj
Joined: 03 Aug 2007
Posts: 1048
Location: near Vienna, Austria
|
| Posted: Mon Aug 11, 2008 4:42 pm Post subject: Re: VH+ by JPF (game 0045) |
|
|
| ravel wrote: | | they also can be rather hard, so be careful. |
Thanks for the warning, ravel. That is a long way through basics ...
In case anyone wants to skip the drudgery:
| Code: |
+--------------------------+--------------------------+--------------------------+
| 5 78 1 | 2 39 6 | 3479 3489 3789 |
| 289 3 289 | 1 7 4 | 5 28 6 |
| 6 27 4 | 8 5 39 | 2379 1 2379 |
+--------------------------+--------------------------+--------------------------+
| 1 28 5 | 7 234 23 | 2349 6 2389 |
| 2389 6 289 | 5 234 1 | 2347 2348 2378 |
| 23 4 7 | 9 6 8 | 1 23 5 |
+--------------------------+--------------------------+--------------------------+
| 28 9 28 | 3 1 7 | 6 5 4 |
| 4 5 3 | 6 8 29 | 29 7 1 |
| 7 1 6 | 4 29 5 | 8 239 239 |
+--------------------------+--------------------------+--------------------------+
|
play online
swordfish(2) and x-wing/coloring(9) seem to be a good start:
the swordfish gets rid of 2 in r9c8, which opens an xy-wing.
the x-wing removes 9 from r9c9, which opens another xy-wing
Also, a w-wing (28) r7c1,r2c8 with strong link (2) in row 6
And, using the strong link on 9 in col 8, a very generalized m-wing (3) r1c5=r9c9 (removes 3 from r1c9, same result as the second xy-wing). |
|
| Back to top |
|
|
nataraj
Joined: 03 Aug 2007
Posts: 1048
Location: near Vienna, Austria
|
| Posted: Mon Aug 11, 2008 5:28 pm Post subject: |
|
|
After cleanup, a w-wing (3) r4c6=r6c8 via strong link (2) in row 5 removes 3 from r4c7 and r4c9
| Code: |
+--------------------------+--------------------------+--------------------------+
| 5 78 1 | 2 39 6 | 34 349 78 |
| 289 3 289 | 1 7 4 | 5 28 6 |
| 6 27 4 | 8 5 39 | 2379 1 2379 |
+--------------------------+--------------------------+--------------------------+
| 1 28 5 | 7 234 23* |-349 6 2-389 |
| 389 6 89 | 5 234# 1 | 347 348 2378# |
| 23 4 7 | 9 6 8 | 1 23* 5 |
+--------------------------+--------------------------+--------------------------+
| 28 9 28 | 3 1 7 | 6 5 4 |
| 4 5 3 | 6 8 29 | 29 7 1 |
| 7 1 6 | 4 29 5 | 8 39 23 |
+--------------------------+--------------------------+--------------------------+
|
at which point an m-wing (49 in r4c7, (4)r1c7=r1c8 and (9)r1c8=r9c8) eliminates 9 in r8c7 and the puzzle finally is solved. |
|
| Back to top |
|
|
ravel
Joined: 21 Apr 2006
Posts: 536
|
| Posted: Tue Aug 12, 2008 8:47 pm Post subject: |
|
|
My warning was about the puzzles with ratings SE 6.9 to 7.2, not the ones i selected 
This one is "very easy" after basics. Obviously Myth Jellies and Asellus have not seen it so far. I was lucky to find it.
Its a one-quick-trick-pony. |
|
| Back to top |
|
|
Asellus
Joined: 05 Jun 2007
Posts: 865
Location: Sonoma County, CA, USA
|
| Posted: Tue Aug 12, 2008 9:57 pm Post subject: |
|
|
| ravel wrote: | | Obviously Myth Jellies and Asellus have not seen it so far. |
I've seen it now. There's a 6-cell 289 DP in the left tower: r5c1 must be <3>, easily solving the puzzle. (Sorry, nataraj!) |
|
| Back to top |
|
|
storm_norm
Joined: 18 Oct 2007
Posts: 1741
|
| Posted: Tue Aug 12, 2008 10:05 pm Post subject: |
|
|
| Ravel, are you stopping your posting career on this site at 999?? |
|
| Back to top |
|
|
nataraj
Joined: 03 Aug 2007
Posts: 1048
Location: near Vienna, Austria
|
| Posted: Fri Aug 15, 2008 11:28 am Post subject: |
|
|
| Asellus wrote: | | There's a 6-cell 289 DP in the left tower: r5c1 must be <3>, easily solving the puzzle. (Sorry, nataraj!) |
Ah, but no reason to be sorry. I know those DPs going beyond simple rectangular shapes are on my "to get comfortable with" list. Matter of fact, I looked at those cells but could not make a useful elimination. Even now I see the 28s in r8 quite clearly but how to construct a usable DP in r2 and r5, especially with the 27 and 28 cells in boxes 1 and 4 - still eludes me. Could you please spare a few more words .. is this a DP with tri-value cells or just a regular 28-29-89 pattern?
I have been away for a few days, travelling in Europe, and will be away from home for the better part of next week , but I hope to have broadband internet access at least in some of the hotels, so I don't miss my daily sudoku fix ... (getting much closer to kragzy's time zone; maybe I'll be posting about "today"'s vh when you guys in the USofA are coming home from the office, that's going to be weird ...)
See you all again a week from now (or earlier if technology permits). BTW, I had the same problem as keith (what to take on a trip to a desert island) and took a supply of this site's VHs (Aug-Nov last year, hoping I've forgotten the solutions) some Times fiendish and super fiendish, and a HSDPA/GSM card for my notebook just in case 
Keep up the good work! |
|
| Back to top |
|
|
Asellus
Joined: 05 Jun 2007
Posts: 865
Location: Sonoma County, CA, USA
|
| Posted: Fri Aug 15, 2008 7:09 pm Post subject: |
|
|
| nataraj wrote: | | Ah, but no reason to be sorry. |
None, indeed. It was 'said' tongue-in-cheek ... a much too lame attempt at humor, I'm afraid.
| nataraj wrote: | | Could you please spare a few more words .. is this a DP with tri-value cells or just a regular 28-29-89 pattern? |
The conjugate <9>s in the r2 trivalues are the key. In effect, this will either be an 89 pair or a 29 pair. In the former case, it is a Type 1 UR. In the latter case, it is a "Type 1" 29-89-28 6-cell bivalue DP. Either way, r5c1 is 3. |
|
| Back to top |
|
|
ravel
Joined: 21 Apr 2006
Posts: 536
|
| Posted: Sat Aug 16, 2008 2:04 pm Post subject: |
|
|
In Myth Jellies' thread you can find some multidigit deadly patterns. If you look at this one
3-digit 2-row 3-column 3-box
| Code: | . abc . | . abc . | . abc .
. abc . | . abc . | . abc .
. . . | . . . | . . .
-----------+-----------+-----------
|
it is immediately clear, that also
| Code: | . abc . | . abc . | . ab .
. abc . | . abc . | . ab .
. . . | . . . | . . .
-----------+-----------+-----------
|
is deadly.
Another way to see it is:
If you have a solution
| Code: | . 1 . | . 2 . | . 3 .
. 2 . | . 3 . | . 1 .
. . . | . . . | . . .
---------+---------+---------
|
you always can swap the numbers in rows 1 and 2 to get a second solution (provided that none is a given here).
The reason is, that you have pairs in columns and boxes and triples in the rows. So no 1, 2 or 3 in the solution can prevent this swapping.
And any solution you can get with the above patterns will have the same properties. |
|
| Back to top |
|
|
cgordon
Joined: 04 May 2007
Posts: 769
Location: ontario, canada
|
| Posted: Sat Aug 16, 2008 9:53 pm Post subject: |
|
|
| What's a DP? - A Deadly Pattern? I've recently noticed a surge in the use of this acronym. I see a Type 2 UR which knocks of a 9 in B1 - which then leads to an x-wing on 9. But can't get further - still too much clutter in B3 and 6. |
|
| Back to top |
|
|
Asellus
Joined: 05 Jun 2007
Posts: 865
Location: Sonoma County, CA, USA
|
| Posted: Sun Aug 17, 2008 4:10 am Post subject: |
|
|
As ravel points out, my use of the conjugate <9>s was over-determining. I rather thought it might be.
Craig,
Yes, DP is Deadly Pattern. I see a 28 Type 2 UR in r27c13, but it has no victims. So, I'm not following you. Maybe you're seeing something else? In any case, the 6-cell DP we are discussing immediately determines r5c1=3 and solves the puzzle. Forgoing that, nataraj's solution works as an alternative. |
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
