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 

NO silliness...a Very Hard

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



Joined: 06 May 2017
Posts: 570

PostPosted: Fri Mar 02, 2018 2:41 pm    Post subject: NO silliness...a Very Hard Reply with quote

Drop this one on the Draw/Play and grade it for yourself.
A Very Hard Puzzle...proceed accordingly...and enjoy the puzzle....

Code:

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

Play this puzzle online at the Daily Sudoku site

cheers...immp
Back to top
View user's profile Send private message
keith



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

PostPosted: Fri Mar 02, 2018 3:47 pm    Post subject: Reply with quote

Multi-step, fishy thing.

Keith
Back to top
View user's profile Send private message
Ajò Dimonios



Joined: 01 May 2017
Posts: 339
Location: Sassari Italy

PostPosted: Fri Mar 02, 2018 6:23 pm    Post subject: Reply with quote

Hi everyone

Code:

+----------------+------------+---------------+
| 9    6    1    | 8   3   7  | 5    4    2   |
| 257  25   3    | 6   4   29 | 1    789  89  |
| 8    24   247  | 1   29  5  | 6    79   3   |
+----------------+------------+---------------+
| 24   1    6    | 9   5   8  | 24   3    7   |
| 3457 9    4578 | 347 27  24 | 48   6    1   |
| 2347 2348 2478 | 347 1   6  | 2489 589  589 |
+----------------+------------+---------------+
| 6    7    89   | 5   89  1  | 3    2    4   |
| 1235 2358 2589 | 47  789 49 | 89   1589 6   |
| 145  458  4589 | 2   6   3  | 7    1589 589 |
+----------------+------------+---------------+

Play this puzzle online at the Daily Sudoku site

Solution with one move.

[9R7C5-(9=2)R3C5-(2=4)R3C2; 9R7C5-(9=8)R7C3-8R9C2; (9-8)R7C5=8R8C5-(8=9)R8C7-9R9C9 and 9R7C5-9R3C5=9R2C6-(9=8)R2C9-(8=5)R9C9-(5=4)R9C2]=>contradiction (two certain 4 in column 2)=>-9R7C5=>Stte.
Ciao a Tutti
Paolo
Back to top
View user's profile Send private message
ZeroAssoluto



Joined: 05 Feb 2017
Posts: 868
Location: Rimini, Italy

PostPosted: Fri Mar 02, 2018 7:47 pm    Post subject: Reply with quote

Hi everyone,

after basic

Code:

+----------------+------------+---------------+
| 9    6    1    | 8   3   7  | 5    4    2   |
| 257  25   3    | 6   4   29 | 1    789  89  |
| 8    24   247  | 1   29  5  | 6    79   3   |
+----------------+------------+---------------+
| 24   1    6    | 9   5   8  | 24   3    7   |
| 3457 9    4578 | 347 27  24 | 48   6    1   |
| 2347 2348 2478 | 347 1   6  | 2489 589  589 |
+----------------+------------+---------------+
| 6    7    89   | 5   89  1  | 3    2    4   |
| 1235 235  25   | 47  789 49 | 89   15   6   |
| 145  458  4589 | 2   6   3  | 7    1589 589 |
+----------------+------------+---------------+

Play this puzzle online at the Daily Sudoku site

XY-Chain r8c4 7,4 - r8c6 4,9 - r8c7 9,8 - r5c7 8,4 - r5c6 4,2 - r5c5 2,7 and -7 in r56c4,r8c5.

and

Code:

+---------------+---------+-------------+
| 9    6   1    | 8  3  7 | 5    4   2  |
| 25   25  3    | 6  4  9 | 1    7   8  |
| 8    4   7    | 1  2  5 | 6    9   3  |
+---------------+---------+-------------+
| 24   1   6    | 9  5  8 | 24   3   7  |
| 345  9   458  | 34 7  2 | 48   6   1  |
| 7    238 248  | 34 1  6 | 2489 58  59 |
+---------------+---------+-------------+
| 6    7   89   | 5  89 1 | 3    2   4  |
| 1235 235 25   | 7  89 4 | 89   15  6  |
| 145  58  4589 | 2  6  3 | 7    158 59 |
+---------------+---------+-------------+

Play this puzzle online at the Daily Sudoku site

XY-Wing 5,8,9 in r8c7,r9c29 and -8 in r9c8.

Ciao Gianni
Back to top
View user's profile Send private message
immpy



Joined: 06 May 2017
Posts: 570

PostPosted: Sat Mar 03, 2018 8:33 am    Post subject: Reply with quote

For myself, it was as easy as saying, "Bartender, make it a double."
A double XY-wing, that is.
Look at Paolo's first post after basics. (scroll up)
There is a -489 XY-wing r58c67 pivoted @ r8c7.
This results in an elimination of r5c6<>4 (=2)!
And a good rinsing takes you almost half way through, which
brings us here:


Code:

+---------------+---------+-------------+
| 9    6   1    | 8  3  7 | 5    4   2  |
| 25   25  3    | 6  4  9 | 1    7   8  |
| 8    4   7    | 1  2  5 | 6    9   3  |
+---------------+---------+-------------+
| 24   1   6    | 9  5  8 | 24   3   7  |
| 345  9   458  | 34 7  2 | 48   6   1  |
| 7    238 248  | 34 1  6 | 2489 58  59 |
+---------------+---------+-------------+
| 6    7   89   | 5  89 1 | 3    2   4  |
| 1235 235 25   | 7  89 4 | 89   15  6  |
| 145  58  4589 | 2  6  3 | 7    158 59 |
+---------------+---------+-------------+

Play this puzzle online at the Daily Sudoku site

The second XY-wing is then the 58-9 r7c3 & r9c29 pivoted @ r9c2.
This results in an elimination of r9c3<>9...and solves the puzzle, as it did for Gianni, when he arrived here, as well.


cheers...imp

I LOVE multi-step VHs...!
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