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 

Set T_03 Puzzle 74 -- Advanced

 
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Puzzles by daj
View previous topic :: View next topic  
Author Message
daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Fri Apr 17, 2009 1:44 pm    Post subject: Set T_03 Puzzle 74 -- Advanced Reply with quote

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

Play this puzzle online at the Daily Sudoku site

Code:
         turbot fish/ER  c3b3            <> 5    [r6c9]          extraneous
 c26r4   Skyscraper                      <> 8    [r7c5],[r9c3]

 r6  b5  Locked Candidate 2              <> 5    [r4c6],[r5c46]

         XYZ-Wing [r4c2]/[r1c2]+[r6c3]   <> 7    [r5c2]
         XYZ-Wing [r4c2]/[r4c9]+[r6c3]   <> 7    [r4c1]          extraneous

         Skyscraper      r25c1           <> 7    [r1c4][r6c5]

         XY-Wing  [r1c4]/[r2c6]+[r9c4]   <> 5    [r9c6]          sufficient
         XY-Wing  [r2c6]/[r1c4]+[r9c6]   <> 8    [r9c4]


Last edited by daj95376 on Fri Apr 24, 2009 8:46 pm; edited 1 time in total
Back to top
View user's profile Send private message
storm_norm



Joined: 18 Oct 2007
Posts: 1741

PostPosted: Sat Apr 18, 2009 11:21 pm    Post subject: Reply with quote

Code:
.------------------.------------------.------------------.
| 3     47    2    | 4578  4578  1    | 9     6     45   |
| 457   6     9    | 3     457   45   | 8     1     2    |
| 8     1     45   | 9     2     6    | 45    7     3    |
:------------------+------------------+------------------:
| 457   478   6    | 1     3     2458 | 245   9     457  |
| 4579  479   3    | 457   6     245  | 245   8     1    |
| 1     2     4578 | 4578  4578  9    | 6     3     457  |
:------------------+------------------+------------------:
| 479   4789  478  | 2     48    3    | 1     5     6    |
| 2     5     1    | 6     9     7    | 3     4     8    |
| 6     3     48   | 458   1     458  | 7     2     9    |
'------------------'------------------'------------------'

skyscraper on 8
the next two chains are the same except one makes eliminations before moving on to make more in the second one.
(7=8)r6c3 - (8)r4c2 = (8)r4c6 - (8=5)r9c6 - (5)r2c6 = (5-7)r2c5 = (7)r2c1; r45c1 <> 7
(7=8)r6c3 - (8)r4c2 = (8)r4c6 - (8=5)r9c6 - (5)r2c6 = (5-7)r2c5 = (7)r2c1 - (7=9)r7c1 - (9)r7c2 = (9)r5c2; r5c2 <> 7

xy-wing {4,5,8} removes 5 from r9c6
Back to top
View user's profile Send private message
tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills

PostPosted: Mon Apr 20, 2009 12:58 pm    Post subject: Reply with quote

I had to "work" on this since I could not find a non-chain solution. Three steps:
First, a Kraken x-wing 8 in r16c45 deletes 8 in r7c5.

Then I found a couple of deletions that lead nowhere so I started looking for a chain. After a lengthy time, I found a one that deletes 8 from r6c5.
Code:

*-----------------------------------------------------------*
 | 3     47    2     | 47-8  *78   1     | 9     6     5     |
 | 47    6     9     | 3     *57   *45   | 8     1     2     |
 | 8     1     5     | 9     2     6     | 4     7     3     |
 |-------------------+-------------------+-------------------|
 | 457   478   6     | 1     3     248   | 25    9     47    |
 | 4579  479   3     | 47    6     24    | 25    8     1     |
 | 1     2     78    | 4578  578   9     | 6     3     47    |
 |-------------------+-------------------+-------------------|
 | 79    789   78    | 2     4     3     | 1     5     6     |
 | 2     5     1     | 6     9     7     | 3     4     8     |
 | 6     3     4     | *58   1     *58   | 7     2     9     |
 *-----------------------------------------------------------*


(8=5)r9c4 - (5)r9c6 = (5)r2c6 - (5=7)r2c5 - (7=8)r1c5; r1c4<>8.

And finally, a xy-wing 478 with pivot 48 at r4c2 deletes 7 at r5c2, but transporting the 7 at r1c2 to r2c5 via r1c4 deletes 7 at r6c5 to finish off the puzzle.

Ted
Back to top
View user's profile Send private message
arkietech



Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA

PostPosted: Mon Apr 20, 2009 6:42 pm    Post subject: Reply with quote

Code:
A w-wing, Skscrapers and xyz-wings led to this
.-------------.-------------.----------.
| 3   47   2  | 48   78  1  | 9  6  5  |
| 47  6    9  | 3    57  45 | 8  1  2  |
| 8   1    5  | 9    2   6  | 4  7  3  |
:-------------+-------------+----------:
| 5   78   6  | 1    3   48 | 2  9  47 |
| 49  49   3  | 7    6   2  | 5  8  1  |
| 1   2    78 | 458  58  9  | 6  3  47 |
:-------------+-------------+----------:
| 79  789  78 | 2    4   3  | 1  5  6  |
| 2   5    1  | 6    9   7  | 3  4  8  |
| 6   3    4  | 58   1   58 | 7  2  9  |
'-------------'-------------'----------'
w-wing 48 with 8 in row9 solves it

dan
Back to top
View user's profile Send private message
Marty R.



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

PostPosted: Wed Apr 22, 2009 4:57 am    Post subject: Reply with quote

Took me seven steps. M (45), ER (Cool, XYZ (478), W (47), DP (25-24-45), Remote Pairs (47) and a finishing XY (487).
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Puzzles by daj 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