SudoCue Users Forum Index SudoCue Users
A forum for users of the SudoCue programs and the services of SudoCue.Net
 
 FAQFAQ   SearchSearch   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

28 Dec 2006 Nightmare: Quick Solution

 
Post new topic   Reply to topic    SudoCue Users Forum Index -> Daily Sudoku Nightmare & Archive
View previous topic :: View next topic  
Author Message
Ron Moore
Addict
Addict


Joined: 13 Aug 2006
Posts: 72
Location: New Mexico

PostPosted: Thu Dec 28, 2006 6:12 pm    Post subject: 28 Dec 2006 Nightmare: Quick Solution Reply with quote

This is the position in the 28 Dec 2006 Nightmare, after initial eliminations from basic techniques:
Code:
.------------------.-------------------.------------------.
| 1237  4    *236  | 9     56     8    | 567   27    137  |
| 237  *267   9    | 56    4      1    | 5678  278   378  |
| 5    *16    8    | 3     2      7    | 69    4     19   |
:------------------+-------------------+------------------:
| 18   *156   4    | 56    13567  35   | 78    9     2    |
|-289  *256  *26   |-24    5679  -2459 | 3     1     78   |
| 1-29  3     7    | 8     19     29   | 4     56    56   |
:------------------+-------------------+------------------:
| 4     8     1    | 7     59     6    | 2     3     59   |
| 6     27    5    | 1     389    2349 | 789   78    4789 |
| 237   9     23   | 24    58     245  | 1     5678  45678|
'------------------'-------------------'------------------'

After eliminations from the following chain (cells marked with "*" in the diagram), the solution is completed with singles only:
    (2=6)r5c3 - (6)r1c3 = (6)r2c2 - (6=152)r345c2 => r5c146, r6c1 <> 2
Back to top
View user's profile Send private message
Myth Jellies
Hooked
Hooked


Joined: 04 Apr 2006
Posts: 42

PostPosted: Fri Jan 05, 2007 1:16 am    Post subject: Reply with quote

Hate to spoil your fun, Ron; but if your grid is correct, there is no obvious (6)r1c3 = (6)r2c2 strong link. The 6 in r3c2 messes you up.

There is a nice little 56-UR in r69c89 which can only be escaped via the 5 in r7c9. Might as well hit the low hanging fruit.
Back to top
View user's profile Send private message
Ron Moore
Addict
Addict


Joined: 13 Aug 2006
Posts: 72
Location: New Mexico

PostPosted: Mon Jan 08, 2007 12:57 am    Post subject: Guilty as Charged Reply with quote

Ugh! No excuse for that. I think I had one too many (puzzles at one stretch).
Back to top
View user's profile Send private message
rcbroughton
Expert
Expert


Joined: 15 Nov 2006
Posts: 143
Location: London

PostPosted: Tue Jan 09, 2007 7:16 pm    Post subject: Reply with quote

Once you do the simple eliminations from the UR, there is a strong chain on 7 at r9c9->r9c1->r8c2->r2c2 that eliminates 7 from r2c9

followed by a strong/weak chain on value 2 at r5c2->r5c4->r9c4->r8c6->r8c2 eliminating 2 from r5c2

after another cople of simple steps there's a strong/weak chain on 5 at r1c5->r2c4->r2c7->r3c7->r3c9->r3c2->r5c2 removing 5 from r5c5

There are then a couple of real tricky to spot chains
r5c9->r4c7->r4c1->r4c2->r3c2->r3c9->r3c7->r2c7->r2c4->r1c5->r9c5 removing 8 from r9c9

then (1)r1c1->(1)r1c9->(3)r1c9->(3)r2c9->(8)r2c9->(8)r2c8->(2)r2c8->(2)r1c8 removing 2 from r1c1 and 1 from r1c8

then (1)r1c1->(1)r1c9->(3)r1c9->(3)r2c9->(8)r2c9->(8)r2c8->(8)r8c8->(7)r8c8->(7)r8c2->(7)r2c2 removing 7 from r1c1 and 1 from r2c2

finally r1c1->r3c2->r4c2->r4c1->r4c7->r5c9->r2c9 3 from r1c9 r2c1

after that, it's singles
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    SudoCue Users Forum Index -> Daily Sudoku Nightmare & Archive 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