dailysudoku.com :: View topic - A little more than VH

dailysudoku.com
Discussion of Daily Sudoku puzzles

FAQ

Memberlist

Usergroups

Profile

A little more than VH

dailysudoku.com Forum Index -> Other puzzles

View previous topic :: View next topic

Author

Message

keith

Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA

Posted: Sun Jun 08, 2008 2:32 pm Post subject: A little more than VH

This is today's Mepham competition puzzle:

Code:

Puzzle: MM060808d
+-------+-------+-------+
| . . . | 6 . . | 4 . . |
| . . 5 | . 2 3 | . . . |
| . . 7 | 1 . 9 | . . 6 |
+-------+-------+-------+
| . 4 . | . . . | . . 9 |
| . 5 . | . . . | . 3 . |
| 8 . 9 | . . . | 7 5 . |
+-------+-------+-------+
| 6 . . | 2 . 4 | 5 . . |
| . . . | 5 3 . | 8 . . |
| . . 3 | . . 6 | . . . |
+-------+-------+-------+

Keith

storm_norm

Joined: 18 Oct 2007
Posts: 1741

Posted: Sun Jun 08, 2008 5:12 pm Post subject:

Code:

.------------------.------------------.------------------.
| 129 3 12 | 6 78 78 | 4 19 5 |
| 19 6 5 | 4 2 3 | 19 78 78 |
| 4 8 7 | 1 5 9 | 3 2 6 |
:------------------+------------------+------------------:
| 3 4 26 | 78 178 5 | 26 18 9 |
| 7 5 126 | 9 4 128 | 126 3 128 |
| 8 12 9 | 3 6 12 | 7 5 4 |
:------------------+------------------+------------------:
| 6 17 8 | 2 179 4 | 5 179 3 |
| 12 9 4 | 5 3 17 | 8 6 127 |
| 5 127 3 | 78 1789 6 | 129 4 127 |
'------------------'------------------'------------------'

first thing I see is a UR
then I think a little more examination is required.

edit:
I got it in two moves...first a UR...
second, using an extended M-wing exploiting the {1,9} pairs in boxes 1 and 3

Marty R.

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

Posted: Sun Jun 08, 2008 5:27 pm Post subject:

There's a nice M-Wing on the 12s in boxes 47 which takes out the 1 in r8c6 which looks like it will help considerably.

keith

Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA

Posted: Sun Jun 08, 2008 5:32 pm Post subject:

Norm,

You don't need the UR.

Code:

.------------------.------------------.------------------.
| 129 3 12 | 6 78 78 | 4 19 5 |
| 19 6 5 | 4 2 3 | 19 78 78 |
| 4 8 7 | 1 5 9 | 3 2 6 |
:------------------+------------------+------------------:
| 3 4 26 | 78 178 5 | 26 18 9 |
| 7 5 126 | 9 4 128 | 126 3 128 |
| 8 12b 9 | 3 6 12c | 7 5 4 |
:------------------+------------------+------------------:
| 6 17 8 | 2 179 4 | 5 179 3 |
| 12a 9 4 | 5 3 -17 | 8 6 127 |
| 5 127 3 | 78 1789 6 | 129 4 127 |
'------------------'------------------'------------------'

The way I saw it:

a and b are a complementary pair, they have the same value. (They share the same set of unsolved buddies in B7 and C2.) So, a and c are a remote pair, and you can eliminate <1> in R8C6.

Another way to see it is that a and c are a W-wing, joined by the strong link on <2> in C2.

Keith

storm_norm

Joined: 18 Oct 2007
Posts: 1741

Posted: Sun Jun 08, 2008 6:15 pm Post subject:

keith wrote:

Norm,

You don't need the UR.

Code:

.------------------.------------------.------------------.
| 129 3 12 | 6 78 78 | 4 19 5 |
| 19 6 5 | 4 2 3 | 19 78 78 |
| 4 8 7 | 1 5 9 | 3 2 6 |
:------------------+------------------+------------------:
| 3 4 26 | 78 178 5 | 26 18 9 |
| 7 5 126 | 9 4 128 | 126 3 128 |
| 8 12b 9 | 3 6 12c | 7 5 4 |
:------------------+------------------+------------------:
| 6 17 8 | 2 179 4 | 5 179 3 |
| 12a 9 4 | 5 3 -17 | 8 6 127 |
| 5 127 3 | 78 1789 6 | 129 4 127 |
'------------------'------------------'------------------'

that was nice Keith, I see it. w-wing on {1,2} stong link on 2 removes the 1 in r8c6

Display posts from previous:

	dailysudoku.com Forum Index -> Other puzzles	All times are GMT
Page 1 of 1

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