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 

Impossible Menneske No. 02

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



Joined: 19 Sep 2005
Posts: 3150
Location: near Detroit, Michigan, USA

PostPosted: Tue Feb 26, 2013 11:38 pm    Post subject: Impossible Menneske No. 02 Reply with quote

Code:
 M6912298 Impossible (5997)
+-------+-------+-------+
| . . . | . 8 . | 5 . 7 |
| . 6 . | . . . | . . . |
| 4 . . | 7 . . | . 1 . |
+-------+-------+-------+
| . . 1 | . . . | . 8 9 |
| . . . | . . 5 | 2 . . |
| 7 . . | . 9 . | 4 . . |
+-------+-------+-------+
| . . . | . . 6 | . . 4 |
| . . 2 | 1 . . | . 9 . |
| . . 6 | 5 . . | . . . |
+-------+-------+-------+

Play this puzzle online at the Daily Sudoku site

Ask, ye shall receive!

Keith


Last edited by keith on Sun Mar 17, 2013 4:29 am; edited 1 time in total
Back to top
View user's profile Send private message
JC Van Hay



Joined: 13 Jun 2010
Posts: 365
Location: Charleroi, Belgium

PostPosted: Wed Feb 27, 2013 10:39 am    Post subject: Reply with quote

#1. r56c9=1=r79c7, r5c3=4, r6c89=5=r4c12, r2c3=7
#2. Chain[2] : Finned XWing(6R16) : r1c8=r1c4-r6c4=r6c89 :=> -6r5c8

Strongest digits : 5,6,1 whose X Chains are weakly coupled in r23c5 and r6c89.
They enter the following loop :
Code:
+----------------------+---------------------------+-----------------------+
| 1239    1239    39   | 2349(6)  8         12349  | 5     234(6)  7       |
| 123589  6       7    | 2349     -234(15)  12349  | 389   234     238     |
| 4       23589   3589 | 7        -23(56)   239    | 3689  1       2368    |
+----------------------+---------------------------+-----------------------+
| 2356    235     1    | 2346     23467     2347   | 367   8       9       |
| 3689    389     4    | 368      367(1)    5      | 2     37      36(1)   |
| 7       238     38   | 2368     9         1238   | 4     -3(56)  -36(15) |
+----------------------+---------------------------+-----------------------+
| 13589   135789  3589 | 2389     237       6      | 1378  2357    4       |
| 358     34578   2    | 1        347       3478   | 3678  9       3568    |
| 1389    134789  6    | 5        2347      234789 | 1378  237     238     |
+----------------------+---------------------------+-----------------------+
Loop[6] : 6r1c4=(6-5)r3c5=(5-1)r2c5=1r5c5-1r5c9=(1-5)r6c9=(5-6)r6c8=6r1c8 @
:=> r3c5=56=r6c8,r2c5=15=r6c9

Adding the chain 5r3c3=5r7c3-5r7c8=5r6c8 to the loop solves the loop because
r6c9=5->no 5 in Box 2 :=> r6c8=5.
Interpretation :
Code:
+------------------------+--------------------------+--------------------+
| 1239    1239    39     | 2349(6)  8        12349  | 5     234(6)  7    |
| 123589  6       7      | 2349     12345    12349  | 389   234     238  |
| 4       23589   389(5) | 7        23-5(6)  239    | 3689  1       2368 |
+------------------------+--------------------------+--------------------+
| 2356    235     1      | 2346     23467    2347   | 367   8       9    |
| 3689    389     4      | 368      1367     5      | 2     37      136  |
| 7       238     38     | 2368     9        1238   | 4     3(56)   1356 |
+------------------------+--------------------------+--------------------+
| 13589   135789  389(5) | 2389     237      6      | 1378  237(5)  4    |
| 358     34578   2      | 1        347      3478   | 3678  9       3568 |
| 1389    134789  6      | 5        2347     234789 | 1378  237     238  |
+------------------------+--------------------------+--------------------+
#3. Chain[4] : 5r3c3=5r7c3-5r7c8=(5-6)r6c8=6r1c8-6r1c4=6r3c5 :=> -5r3c5; 18 Singles; r79c8=23 :=> r9c9=8
#4. Chain[2] : Skyscraper(8C36) : r7c3=r6c3-r6c6=r8c6 :=> -8r7c4.r8c12;ste
Back to top
View user's profile Send private message
oaxen



Joined: 10 Jul 2006
Posts: 96

PostPosted: Fri Mar 01, 2013 6:17 pm    Post subject: Reply with quote

This was the hardes puzzles I ever met. I solved it, but canīt remember the step I took. something like van hay anyhow.
Back to top
View user's profile Send private message Visit poster's website
DonM



Joined: 15 Sep 2009
Posts: 51

PostPosted: Fri Mar 01, 2013 9:10 pm    Post subject: Reply with quote

oaxen wrote:
This was the hardes puzzles I ever met. I solved it, but canīt remember the step I took.


I hate when that happens. Smile
Back to top
View user's profile Send private message
keith



Joined: 19 Sep 2005
Posts: 3150
Location: near Detroit, Michigan, USA

PostPosted: Fri Mar 01, 2013 10:32 pm    Post subject: Reply with quote

DonM wrote:
oaxen wrote:
This was the hardes puzzles I ever met. I solved it, but canīt remember the step I took.


I hate when that happens. Smile


oaxen,

I said:
Quote:
Ask, ye shall receive!
Very Happy

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



Joined: 15 Sep 2009
Posts: 51

PostPosted: Fri Mar 01, 2013 10:55 pm    Post subject: Reply with quote

Menneske Impossible 2 ssts ER=7.3
Code:
*-----------------------------------------------------------------------------*
 | 1239    1239    39      | 23469   8       12349   | 5       2346    7       |
 | 123589  6       7       | 2349    12345   12349   | 389     234     238     |
 | 4       23589   3589    | 7       2356    239     | 3689    1       2368    |
 |-------------------------+-------------------------+-------------------------|
 | 2356    235     1       | 2346    23467   2347    | 367     8       9       |
 | 3689    389     4       | 368     1367    5       | 2       367     136     |
 | 7       238     38      | 2368    9       1238    | 4       356     1356    |
 |-------------------------+-------------------------+-------------------------|
 | 13589   135789  3589    | 2389    237     6       | 1378    2357    4       |
 | 358     34578   2       | 1       347     3478    | 3678    9       3568    |
 | 1389    134789  6       | 5       2347    234789  | 1378    237     238     |
 *-----------------------------------------------------------------------------*

1. (5)r7c3=r3c3-r3c5=(5-1)r2c5=r5c5-r5c9=(1-5)r6c9=(5)r6c8 :=> -5r7c8 ->3 singles
Code:
*-----------------------------------------------------------------------------*
 | 1239    1239    39      |*23469   8       12349   | 5      *2346    7       |
 | 123589  6       7       | 2349    12345   12349   | 389     234     238     |
 | 4       23589   3589    | 7       2356    239     | 389     1       2368    |
 |-------------------------+-------------------------+-------------------------|
 | 2356    235     1       |G2346    23467   2347    | 37      8       9       |
 | 3689    389     4       |G368     137-6   5       | 2      *367    G136     |
 | 7       238     38      |*2368    9       1238    | 4       5      *136     |
 |-------------------------+-------------------------+-------------------------|
 | 13589   135789  3589    | 2389    237     6       | 1378    237     4       |
 | 38      3478    2       | 1       347     3478    | 6       9       5       |
 | 1389    134789  6       | 5       2347    234789  | 1378    237     238     |
 *-----------------------------------------------------------------------------*

2.(6)r45c4=[(6)BW:(6)r1c48,r5c8,r6c49]=(6)r5c9-r3c9=(6)r3c5 => -6r45c5 -> r3c5=6 => cascade of singles
-> np(89)r23c7 => r9c9=8 -> skyscraper(8)r5c4,r6c3,r7c34 => -8r6c6
stte

The core of step #2 of the solution is the BW or BrokenWing/Oddagon at (6)r1c48, r5c8, r6c49 (marked by *). This is a potential 5-sided loop of conjugate links of 6s which would be impossible if it existed by itelf. There are three 6s called 'Guardians' (marked by G above) at r4c45 and r5c9 that prevent that pattern. Thus, if guardian (6)r5c9 is not true then guardians (6)r45c4 must be true and vice-versa.

Of interest also: The BW pattern actually eliminates (6)r5c5 immediately because if it were true, it would eliminate all 3 guardians which can't happen. This is interesting because it is rare to find immediate BW eliminations in more complicated puzzles. BTW: Since the chain eliminates both 6s at r45c5 anyway, it isn't necessary to add this as a separate step.

(Keith, enjoyed these 2 puzzles-thanks!)
Back to top
View user's profile Send private message
oaxen



Joined: 10 Jul 2006
Posts: 96

PostPosted: Sat Mar 02, 2013 3:59 pm    Post subject: Reply with quote

Now I have recapitulated. Any of "ones" in block E gives correct five and six in block I. Next valuable bivalues are the "six" in block C. R1C8 leads to a complete puzzle. Very Happy
Back to top
View user's profile Send private message Visit poster's website
arkietech



Joined: 31 Jul 2008
Posts: 1709
Location: Northwest Arkansas USA

PostPosted: Fri Mar 08, 2013 12:31 pm    Post subject: Reply with quote

Code:
 *-----------------------------------------------------------------------------*
 | 1239    1239    39      | 23469   8       12349   | 5       2346    7       |
 | 123589  6       7       | 2349    12345   12349   | 389     234     238     |
 | 4       23589   3589    | 7       2356    239     | 3689    1       2368    |
 |-------------------------+-------------------------+-------------------------|
 | 2356    235     1       | 2346    23467   2347    | 367     8       9       |
 | 3689    389     4       | 368     1367    5       | 2       367     136     |
 | 7       238     38      | 2368    9       1238    | 4       356     1356    |
 |-------------------------+-------------------------+-------------------------|
 | 13589   135789  3589    | 2389    237     6       | 1378    2357    4       |
 | 358     34578   2       | 1       347     3478    | 3678    9       3568    |
 | 1389    134789  6       | 5       2347    234789  | 1378    237     238     |
 *-----------------------------------------------------------------------------*
net
5r3c5 5r7c3 5r6c8 6r6c9 6r1c8
5r3c5 6r1c4
contradiction -5r3c5
 
 *--------------------------------------------------------------------*
 | 1239   139    39     | 2349   8      12349  | 5      6      7      |
 | 12389  6      7      | 239    5      1239   | 89     4      23     |
 | 4      389    5      | 7      6      239    | 89     1      23     |
 |----------------------+----------------------+----------------------|
 | 6      5      1      | 24     247    247    | 3      8      9      |
 | 389    389    4      |f38     1      5      | 2      7      6      |
 | 7      2     *38     | 6      9      3-8    | 4      5      1      |
 |----------------------+----------------------+----------------------|
 | 5      13789 *389    |*289    237    6      | 17     23     4      |
 | 38     3478   2      | 1      347    478    | 6      9      5      |
 | 139    13479  6      | 5      2347   2479   | 17     23     8      |
 *--------------------------------------------------------------------*
Sashimi X-Wing
r67c34,fr5c4 => -8r6c6; ste
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