| View previous topic :: View next topic |
| Author |
Message |
LloydB
Joined: 09 Jul 2007
Posts: 21
Location: Skagit Co., WA USA
|
 Posted: Wed Sep 17, 2008 10:48 am Post subject: Sep 17 VH |
 |
|
I must have missed some easier way, but the way I solved it was certainly fun.
An X-wing on 3 and another on 7 unlocked a series of 3 XY-wings (147, 247, 249) to finally solve it.
It will be interesting to see if all these were necessary for others. |
|
| Back to top |
|
 |
tlanglet
Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
|
| Posted: Wed Sep 17, 2008 12:23 pm Post subject: Re: Sep 17 VH |
|
|
| LloydB wrote: | I must have missed some easier way, but the way I solved it was certainly fun.
An X-wing on 3 and another on 7 unlocked a series of 3 XY-wings (147, 247, 249) to finally solve it.
It will be interesting to see if all these were necessary for others. |
Well Lloyd, you seemed to have had more fun than I did. I noticed a skyscraper while doing basics, which was all that was necessary to do the job.
Details:
| Quote: | | Skyscraper on <9> r2c68; deletes r5c5 & r6c7. |
Ted |
|
| Back to top |
|
|
cgordon
Joined: 04 May 2007
Posts: 769
Location: ontario, canada
|
| Posted: Wed Sep 17, 2008 12:56 pm Post subject: |
|
|
| I used a rather elegant ER solution from the two <9>s in C6 and the T shaped hinge in Box3. This elimated the <9> in R6C7 to leave a <3> in R5C5. |
|
| Back to top |
|
|
Marty R.
Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
|
| Posted: Wed Sep 17, 2008 3:50 pm Post subject: |
|
|
| I also used an ER on 9, which was preceded by two hidden URs, which apparently weren't necessary, but I did see them first. |
|
| Back to top |
|
|
Earl
Joined: 30 May 2007
Posts: 677
Location: Victoria, KS
|
| Posted: Wed Sep 17, 2008 4:42 pm Post subject: Sept 17 VH |
|
|
After simple basics, there is a finned x-wing which eliminates the 9 in R2C6 and solves the puzzle.
Earl |
|
| Back to top |
|
|
arkietech
Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA
|
| Posted: Wed Sep 17, 2008 6:42 pm Post subject: |
|
|
| Code: |
*-----------*
|..1|.67|..2|
|6..|3..|8..|
|..2|...|..5|
|---+---+---|
|.9.|.54|...|
|...|2.1|...|
|...|67.|.8.|
|---+---+---|
|2..|...|3..|
|..4|..6|..9|
|5..|98.|6..|
*-----------*
*-----------------------------------------------------------*
| 489 48 1 | 5 6 7 | 49 3 2 |
| 6 457 57 | 3 1249 *29 | 8 *1479 147 |
| 3479 347 2 | 14 149 8 | 1479 6 5 |
|-------------------+-------------------+-------------------|
| 137 9 6 | 8 5 4 | 127 127 137 |
| 347 3457 8 | 2 3-9 1 | 4579 *4579 6 |
| 134 2 35 | 6 7 *39 | 145-9 8 134 |
|-------------------+-------------------+-------------------|
| 2 6 9 | 147 14 5 | 3 17 8 |
| 378 1378 4 | 17 23 6 | 1257 1257 9 |
| 5 137 37 | 9 8 23 | 6 1247 147 |
*-----------------------------------------------------------*
an er solves the puzzle |
|
|
| Back to top |
|
|
DennyOR
Joined: 12 Sep 2007
Posts: 33
Location: Portland, Oregon
|
| Posted: Fri Sep 19, 2008 11:58 pm Post subject: |
|
|
The same grid depicts the 9s skyscraper.
Denny |
|
| Back to top |
|
|
keith
Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA
|
| Posted: Sat Sep 20, 2008 3:41 am Post subject: |
|
|
After basics: | Code: | +----------------+----------------+----------------+
| 489 48 1 | 5 6 7 | 49 3 2 |
| 6 457 57 | 3 1249@ 2-9 | 8 1479@ 147 |
| 3479 347 2 | 14 149# 8 | 1479 6 5 |
+----------------+----------------+----------------+
| 137 9 6 | 8 5 4 | 127 127 137 |
| 347 3457 8 | 2 39@ 1 |4579 4579@ 6 |
| 134 2 35 | 6 7 39 | 1459 8 134 |
+----------------+----------------+----------------+
| 2 6 9 | 147 14 5 | 3 17 8 |
| 378 1378 4 | 17 23 6 | 1257 1257 9 |
| 5 137 37 | 9 8 23 | 6 1247 147 |
+----------------+----------------+----------------+ |
Sudoku Susser uses two X-wings then FOUR XY-wings to solve it.
My one-stepper is a finned X-wing: either the X-wing on <9> @ in C58 is true, or R3C5 is true. Either way, R2C6 is not <9>.
Keith
(Edit: I see that Earl already pointed this out.) |
|
| Back to top |
|
|
crunched
Joined: 05 Feb 2008
Posts: 168
|
| Posted: Sun Sep 21, 2008 10:11 pm Post subject: |
|
|
I was able to solve this puzzle with a skyscraper---which I hate those things since I seldom can find them.
Only one person here has said that the basic wings solved this, i.e., x wings, xy wings, or xyz wings. For my money those wings could not solve it. I could not find any x wings here.
What am I missing? This is as far as I could go w/o using a 'scraper.
BTW a scraper takes out a 9 in c7, r6, which in turn puts a 9 in c6, r6. The rest of the puzzle then resolves after that.
But I still want to solve this by basic wings, as one person (Lloyd) claims to have done.
| Code: |
+--------------+-------------+---------------+
| 489 48 1 | 5 6 7 | 49 3 2 |
| 6 457 57 | 3 1249 29 | 8 1479 147 |
| 3479 347 2 | 14 149 8 | 1479 6 5 |
+--------------+-------------+---------------+
| 137 9 6 | 8 5 4 | 127 127 137 |
| 347 3457 8 | 2 39 1 | 4579 4579 6 |
| 134 2 35 | 6 7 39 | 1459 8 134 |
+--------------+-------------+---------------+
| 2 6 9 | 147 14 5 | 3 17 8 |
| 378 1378 4 | 17 23 6 | 1257 1257 9 |
| 5 137 37 | 9 8 23 | 6 1247 147 |
+--------------+-------------+---------------+
|
Play this puzzle online at the Daily Sudoku site |
|
| Back to top |
|
|
tlanglet
Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
|
| Posted: Mon Sep 22, 2008 12:06 am Post subject: |
|
|
| crunched wrote: | I could not find any x wings here.
What am I missing?
| Code: |
+--------------+-------------+---------------+
| 489 48 1 | 5 6 7 | 49 3 2 |
| 6 457 57 | 3 1249 29 | 8 1479 147 |
| 3479 347 2 | 14 149 8 | 1479 6 5 |
+--------------+-------------+---------------+
| 137 9 6 | 8 5 4 | 127 127 137 |
| 347 3457 8 | 2 39 1 | 4579 4579 6 |
| 134 2 *35| 6 7 *39| 1459 8 134 |
+--------------+-------------+---------------+
| 2 6 9 | 147 14 5 | 3 17 8 |
| 378 1378 4 | 17 23 6 | 1257 1257 9 |
| 5 137 *37| 9 8 *23| 6 1247 147 |
+--------------+-------------+---------------+
|
|
crunched, I believe the x-wing on <3> in is r69c36 as noted above.
Ted |
|
| Back to top |
|
|
keith
Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA
|
| Posted: Mon Sep 22, 2008 1:34 am Post subject: |
|
|
| Quote: | | But I still want to solve this by basic wings, as one person (Lloyd) claims to have done. |
After basics: | Code: | +----------------+----------------+----------------+
| 489 48 1 | 5 6 7 | 49 3 2 |
| 6 457 57 | 3 1249 29 | 8 1479 147 |
| 3479 347 2 | 14 149 8 | 1479 6 5 |
+----------------+----------------+----------------+
| 137 9 6 | 8 5 4 | 127 127 137 |
| 347 3457 8 | 2 39 1 | 4579 4579 6 |
| 134 2 35 | 6 7 39 | 1459 8 134 |
+----------------+----------------+----------------+
| 2 6 9 | 147 14 5 | 3 17 8 |
| 378 1378 4 | 17 23 6 | 1257 1257 9 |
| 5 137 37 | 9 8 23 | 6 1247 147 |
+----------------+----------------+----------------+ |
Squares R6C3 and R9C3 in column 3 and R6C6 and R9C6 in column 6 form a Simple X-Wing pattern on possibility <3>. All other instances of this possibility in rows 6 and 9 can be removed.
R6C1 - can remove <3> from <134> leaving <14>.
R9C2 - can remove <3> from <137> leaving <17>.
R6C9 - can remove <3> from <134> leaving <14>.
Leading to: | Code: | +----------------+----------------+----------------+
| 489 48 1 | 5 6 7 | 49 3 2 |
| 6 457 57 | 3 1249 29 | 8 1479 147 |
| 3479 347 2 | 14 149 8 | 1479 6 5 |
+----------------+----------------+----------------+
| 17 9 6 | 8 5 4 | 127 127 3 |
| 347 3457 8 | 2 39 1 | 4579 4579 6 |
| 14 2 35 | 6 7 39 | 59 8 14 |
+----------------+----------------+----------------+
| 2 6 9 | 147 14 5 | 3 17 8 |
| 378 1378 4 | 17 23 6 | 1257 1257 9 |
| 5 17 37 | 9 8 23 | 6 1247 147 |
+----------------+----------------+----------------+ |
Squares R2C3 and R9C3 in column 3 and R2C9 and R9C9 in column 9 form a Simple X-Wing pattern on possibility <7>. All other instances of this possibility in rows 2 and 9 can be removed.
R2C2 - can remove <7> from <457> leaving <45>.
R9C2 - can remove <7> from <17> leaving <1>.
R2C8 - can remove <7> from <1479> leaving <149>.
R9C8 - can remove <7> from <1247> leaving <124>.
Leading to:
| Code: | +----------------+----------------+----------------+
| 489 48 1 | 5 6 7 | 49 3 2 |
| 6 45 57 | 3 1249 29 | 8 149 147 |
| 3479 347 2 | 14 149 8 | 1479 6 5 |
+----------------+----------------+----------------+
| 17 9 6 | 8 5 4 | 127 127 3 |
| 347 3457 8 | 2 39 1 | 4579 4579 6 |
| 14 2 35 | 6 7 39 | 59 8 14 |
+----------------+----------------+----------------+
| 2 6 9 | 147 14 5 | 3 17 8 |
| 378 378 4 | 17 23 6 | 1257 1257 9 |
| 5 1 37 | 9 8 23 | 6 24 47 |
+----------------+----------------+----------------+ |
Squares R9C9 (XY), R6C9 (XZ) and R7C8 (YZ) form an XY-Wing pattern on <1>. All squares that are buddies of both the XZ and YZ squares cannot be <1>.
R4C8 - can remove <1> from <127> leaving <27>.
Leading to:
| Code: | +----------------+----------------+----------------+
| 489 48 1 | 5 6 7 | 49 3 2 |
| 6 45 57 | 3 1249 29 | 8 149 147 |
| 3479 347 2 | 14 149 8 | 1479 6 5 |
+----------------+----------------+----------------+
| 17 9 6 | 8 5 4 | 127 27 3 |
| 347 3457 8 | 2 39 1 | 4579 4579 6 |
| 14 2 35 | 6 7 39 | 59 8 14 |
+----------------+----------------+----------------+
| 2 6 9 | 147 14 5 | 3 17 8 |
| 378 378 4 | 17 23 6 | 1257 1257 9 |
| 5 1 37 | 9 8 23 | 6 24 47 |
+----------------+----------------+----------------+ |
Squares R9C8 (XY), R4C8 (XZ) and R9C9 (YZ) form an XY-Wing pattern on <7>. All squares that are buddies of both the XZ and YZ squares cannot be <7>.
R7C8 - can remove <7> from <17> leaving <1>.
R8C8 - can remove <7> from <1257> leaving <125>.
Leading to: | Code: | +----------------+----------------+----------------+
| 489 48 1 | 5 6 7 | 49 3 2 |
| 6 45 57 | 3 129 29 | 8 49 17 |
| 379 37 2 | 4 19 8 | 17 6 5 |
+----------------+----------------+----------------+
| 17 9 6 | 8 5 4 | 12 27 3 |
| 347 3457 8 | 2 39 1 | 459 479 6 |
| 14 2 35 | 6 7 39 | 59 8 14 |
+----------------+----------------+----------------+
| 2 6 9 | 7 4 5 | 3 1 8 |
| 378 378 4 | 1 23 6 | 27 5 9 |
| 5 1 37 | 9 8 23 | 6 24 47 |
+----------------+----------------+----------------+ |
Squares R2C3 (XY), R6C3 (XZ) and R3C2 (YZ) form an XY-Wing pattern on <3>. All squares that are buddies of both the XZ and YZ squares cannot be <3>.
R5C2 - can remove <3> from <3457> leaving <457>.
Leading to: | Code: | +-------------+-------------+-------------+
| 489 48 1 | 5 6 7 | 49 3 2 |
| 6 45 57 | 3 129 29 | 8 49 17 |
| 379 37 2 | 4 19 8 | 17 6 5 |
+-------------+-------------+-------------+
| 17 9 6 | 8 5 4 | 12 27 3 |
| 347 457 8 | 2 39 1 | 459 479 6 |
| 14 2 35 | 6 7 39 | 59 8 14 |
+-------------+-------------+-------------+
| 2 6 9 | 7 4 5 | 3 1 8 |
| 378 378 4 | 1 23 6 | 27 5 9 |
| 5 1 37 | 9 8 23 | 6 24 47 |
+-------------+-------------+-------------+ |
Squares R2C8 (XY), R9C8 (XZ) and R2C6 (YZ) form an XY-Wing pattern on <2>. All squares that are buddies of both the XZ and YZ squares cannot be <2>.
R9C6 - can remove <2> from <23> leaving <3>.
Leading to: Done.
Keith.
(Courtesy of Sudoku Susser) |
|
| Back to top |
|
|
crunched
Joined: 05 Feb 2008
Posts: 168
|
| Posted: Mon Sep 22, 2008 2:01 am Post subject: |
|
|
Beautiful tutorial, thanks.
That was an awesome, exhausting puzzle! |
|
| Back to top |
|
|
RobertRattley
Joined: 24 Jun 2007
Posts: 118
Location: Australia
|
| Posted: Sun Sep 28, 2008 1:26 pm Post subject: Long live the wings |
|
|
Back to LloydB's original post:
I went a simliar path, but made heavier weather of it: a swordfish 3 instead of the x-wing, then the second x-wing. The first two of your 3 xy-wings, but somehow I missed the third. Instead I found an xyz-wing 1,2,7 and after a bit of "hard" type cleanup solved the puzzle.
I certainly do not use ERs, and I agree with those who have noted that so far no puzzle on this site needs anything beyond x-wing (or swordfish), xy-wing and xyz-wing.
I love this kind of sudoku, needing numerous applications of such techniques, in this case an astonishing sequence of 5. It is beyond my imagining how anyone can design such magnificent puzzles.[/quote] |
|
| Back to top |
|
|
|
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
