dailysudoku.com Forum Index dailysudoku.com
Discussion of Daily Sudoku puzzles
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

A difficult puzzle.

 
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Other puzzles
View previous topic :: View next topic  
Author Message
5iyubaobao



Joined: 02 Jan 2008
Posts: 9
Location: BeiJing China

PostPosted: Thu Jan 10, 2008 8:31 am    Post subject: A difficult puzzle. Reply with quote

Hi, all

The following is new puzzle which I can not solve.

Code:

+----------+----------+----------+
| 24  7 8  | 24  6 5  | 1   9 3  |
| 9   3 24 | 248 1 48 | 56  7 56 |
| 5   1 6  | 7   3 9  | 8   4 2  |
+----------+----------+----------+
| 28  9 23 | 458 7 6  | 35  1 45 |
| 17  6 5  | 3   9 14 | 2   8 47 |
| 178 4 13 | 58  2 18 | 357 6 9  |
+----------+----------+----------+
| 6   5 7  | 1   4 2  | 9   3 8  |
| 14  2 14 | 9   8 3  | 67  5 67 |
| 3   8 9  | 6   5 7  | 4   2 1  |
+----------+----------+----------+


I have used many methods, including Strong link and Y-Wing, but can not solve it. So, I use the “Draw/play” again, and it hints the next digital is 3 in R6C3, I wonder how it caculated?

Who know why it is 3? thank you for your time.
Back to top
View user's profile Send private message
ravel



Joined: 21 Apr 2006
Posts: 536

PostPosted: Thu Jan 10, 2008 9:13 am    Post subject: Reply with quote

Code:
+-----------+-----------+----------+
| 24  7  8  | 24  6  5  | 1   9 3  |
| 9   3  24 | 248 1  48 | 56  7 56 |
| 5   1  6  | 7   3  9  | 8   4 2  |
+-----------+-----------+----------+
| 28  9  23 | 458 7  6  | 35  1 45 |
|#17  6  5  | 3   9  14 | 2   8 47 |
|#178 4 -13 | 58  2 #18 | 357 6 9  |
+-----------+-----------+----------+
| 6   5  7  | 1   4  2  | 9   3 8  |
| 14  2  14 | 9   8  3  | 67  5 67 |
| 3   8  9  | 6   5  7  | 4   2 1  |
+-----------+-----------+----------+
There is an xyz-wing in the marked cells. One of them must be 1, so you can eliminate 1 from cells, that see all three.

PS: Here are 3 pretty puzzles by JPF, where you can practice it.

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

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

Code:
 . . . | 1 2 3 | . . .
 . . . | 4 . 5 | . . .
 . . 6 | . . . | 5 . .
-------+-------+-------
 4 7 . | . . . | . 3 5
 3 . . | . . . | . . 2
 2 6 . | . . . | . 8 1
-------+-------+-------
 . . 4 | . . . | 9 . .
 . . . | 2 . 4 | . . .
 . . . | 3 8 7 | . . .   
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Other puzzles All times are GMT
Page 1 of 1

 
Jump to:  
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