View previous topic :: View next topic |
Author |
Message |
storm_norm
Joined: 18 Oct 2007 Posts: 1741
|
Posted: Sat Nov 24, 2007 6:37 am Post subject: diabolical - daily telegraph Nov 23 |
|
|
Code: | -------------------------
| 4 3 5 | . . . | 1 . 2 |
| . . . | . 2 . | . . . |
| . 2 6 | . . . | 5 8 . |
|-----------------------|
| . . 9 | 1 . 6 | 4 . . |
| . . . | . 3 . | . . . |
| . . 8 | 4 . 5 | 2 . . |
|-----------------------|
| . 9 2 | . . . | 3 4 . |
| . . . | . 1 . | . . . |
| 8 . 1 | . . . | 6 2 5 |
-------------------------
http://www.sudoku.telegraph.co.uk/ |
|
|
Back to top |
|
|
nataraj
Joined: 03 Aug 2007 Posts: 1048 Location: near Vienna, Austria
|
Posted: Sat Nov 24, 2007 2:10 pm Post subject: |
|
|
after basics:
Code: |
+--------------------------+--------------------------+--------------------------+
| 4 3 5 | 89 6 89 | 1 7 2 |
| 1 8 7 | 5 2 34 | 9 36 346 |
| 9 2 6 | 37 47 1 | 5 8 34 |
+--------------------------+--------------------------+--------------------------+
| 2 57 9 | 1 8 6 | 4 35 37 |
| 67 15 4 | 279 3 279 | 78 15 6789 |
| 3 167 8 | 4 79 5 | 2 16 679 |
+--------------------------+--------------------------+--------------------------+
| 67 9 2 | 678 5 78 | 3 4 1 |
| 5 46 3 | 26 1 24 | 78 9 78 |
| 8 47 1 | 379 479 3479 | 6 2 5 |
+--------------------------+--------------------------+--------------------------+
|
a useless xy-wing: 74-43-37 pivot r3c9
that can be continued into an xy-chain
'73'(49)='34'(39)='47'(35)='73'(34)='34'(26)='42'(86)='26'(84)='64'(82)='47'(92)='76'(71)='67'(51)
removes "7"s from r4c2 r5c7.
Later on
Code: |
+--------------------------+--------------------------+--------------------------+
| 4 3 5 | 89 6 89 | 1 7 2 |
| 1 8 7 | 5 2 34 | 9 6 34 |
| 9 2 6 | 37 47 1 | 5 8 34 |
+--------------------------+--------------------------+--------------------------+
| 2 5 9 | 1 8 6 | 4 3 7 |
| 67 1 4 | 279 3 279 | 8 5 69 |
| 3 67 8 | 4 79 5 | 2 1 69 |
+--------------------------+--------------------------+--------------------------+
| 67 9 2 | 678 5 78 | 3 4 1 |
| 5 46 3 | 26 1 24 | 7 9 8 |
| 8 47 1 | 379 479 3479 | 6 2 5 |
+--------------------------+--------------------------+--------------------------+
|
a w-wing (47)
'47'(35)='79'(65)='96'(69)='67'(62)='74'(92)
finally solved the puzzle
nice!
thx norm! |
|
Back to top |
|
|
Marty R.
Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
|
Posted: Sat Nov 24, 2007 4:36 pm Post subject: |
|
|
How do these puzzles relate to the diabolicals that appear on Friday and Sunday at sudoku.org.uk? I notice at this site on the printable version the sudoku.org site is mentioned, but the diabolical I have for November 23 is different than this one. |
|
Back to top |
|
|
storm_norm
Joined: 18 Oct 2007 Posts: 1741
|
Posted: Sat Nov 24, 2007 6:11 pm Post subject: |
|
|
Marty R. wrote: | How do these puzzles relate to the diabolicals that appear on Friday and Sunday at sudoku.org.uk? I notice at this site on the printable version the sudoku.org site is mentioned, but the diabolical I have for November 23 is different than this one. |
I noticed last week that the sudoku.org.uk site had changed its address. And I notice that some of the links were giving directions to the new site and some weren't. last evening, I tried clicking on the newspaper link, and I didn't get anything, I got a blank grid. |
|
Back to top |
|
|
ravel
Joined: 21 Apr 2006 Posts: 536
|
Posted: Sun Nov 25, 2007 11:34 am Post subject: |
|
|
nataraj wrote: | a useless xy-wing: 74-43-37 pivot r3c9
that can be continued into an xy-chain | Interestingly i also noticed this xy-wing and tried to "transport" the 7 in r3c5 (btw how did you get the 5 in r8c1 ?) I used the UR 78 to get here:
Code: | *-----------------------------------------------------------*
| 4 3 5 | 89 6 89 | 1 7 2 |
| 1 8 7 | 5 2 34 | 9 36 346 |
| 9 2 6 | 37 47 1 | 5 8 34 |
|-------------------+-------------------+-------------------|
| 2 57 9 | 1 8 6 | 4 35 37 |
|A567 1567 4 |B279 3 B279 | 8 156 69 |
| 3 167 8 | 4 B79 5 | 2 16 679 |
|-------------------+-------------------+-------------------|
| 67 9 2 | 678 5 78 | 3 4 1 |
| 56 456 3 | 26 1 24 | 7 9 8 |
| 8 A47 1 | 379 A479 3479 | 6 2 5 |
*-----------------------------------------------------------*
| With the strong link for 4 in c5 i got
r3c5=7 => r9c5=4 => r9c2=7 (which would exclude 7 from r4c2) => r5c1=7
But i also saw
r3c5=7 => r6c5<>7 => r5c46=7 => r5c1<>7
So i found a contradiction without really searching for one. Then r3c5 must be 4 and the puzzle is solved with an xy-wing. |
|
Back to top |
|
|
re'born
Joined: 28 Oct 2007 Posts: 80
|
Posted: Sun Nov 25, 2007 1:05 pm Post subject: |
|
|
Well, since somebody mentioned transport, here is an overly elaborate solution using transport. After singles:
Code: | *-----------------------------------------------------------*
| 4 3 5 | 89 6 89 | 1 7 2 |
| 1 8 7 | 5 2 34& | 9 36 346 |
| 9 2 6 | 37* 47 1 | 5 8 34 |
|-------------------+-------------------+-------------------|
| 2 57 9 | 1 8 6 | 4 35 37 |
| 67 15 4 | 29-7 3 279* | 78 15 6789 |
| 3 167 8 | 4 79* 5 | 2 16 679 |
|-------------------+-------------------+-------------------|
| 67 9 2 | 678 5 78 | 3 4 1 |
| 5 46 3 | 26 1 24& | 78 9 78 |
| 8 47 1 | 379 479 3479 | 6 2 5 |
*-----------------------------------------------------------* |
I find an "xyz-chain", which implies that one of the *'d cells is a 7. This immediately eliminates 7 from r5c4. Now we transport all three cells:
Code: | *-----------------------------------------------------------*
| 4 3 5 | 89 6 89 | 1 7 2 |
| 1 8 7 | 5 2 34 | 9 36 346 |
| 9 2 6 | 37A 4AB7ab 1 | 5 8 34 |
|-------------------+-------------------+-------------------|
| 2 57 9 | 1 8 6 | 4 35 37 |
| 67c 15 4 | 29 3 27C9 | 78 15 6789 |
| 3 167 8 | 4 7B9 5 | 2 16 679 |
|-------------------+-------------------+-------------------|
| 67C 9 2 | 678 5 78 | 3 4 1 |
| 5 46 3 | 26 1 24 | 78 9 78 |
| 8 4C7c 1 | 379 79-4 3479 | 6 2 5 |
*-----------------------------------------------------------* |
(7)r6c5 and (7)r3c4 are both transported to (7)r3c5, while (7)r5c6 is transported to (4)r9c2 (note that the letters above are not meant to represent conjugates, only to give the reader a quick view of the transport). So now we can eliminate 4 from r9c5. This reduces the puzzle to the following BUG+2:
Code: | *--------------------------------------------------*
| 4 3 5 | 89 6 89 | 1 7 2 |
| 1 8 7 | 5 2 3 | 9 6 4 |
| 9 2 6 | 7 4 1 | 5 8 3 |
|----------------+----------------+----------------|
| 2 5 9 | 1 8 6 | 4 3 7 |
| 67 1 4 | 29 3 27+9 | 8 5 69 |
| 3 67 8 | 4 79 5 | 2 1 69 |
|----------------+----------------+----------------|
| 67 9 2 | 68 5 78 | 3 4 1 |
| 5 46 3 | 26 1 24 | 7 9 8 |
| 8 47 1 | 3 79 49+7 | 6 2 5 |
*--------------------------------------------------* |
from which we deduce r5c6<>7 (as well r9c6<>9), solving the puzzle. |
|
Back to top |
|
|
nataraj
Joined: 03 Aug 2007 Posts: 1048 Location: near Vienna, Austria
|
Posted: Sun Nov 25, 2007 1:15 pm Post subject: |
|
|
ravel wrote: | btw how did you get the 5 in r8c1 ?) |
now that you mention it ... hm. I threw out all sheets from last week this morning. Luckily they're still in the waste-paper-bin (thank god for waste separation).
Seems that before the xy-chain on the right side there was another xy-wing-turned-xy-chain (from that same "useless xy-wing pivot r3c9) removes "5"s over on the left side. I spotted this one fairly easily so it didn't make it into my post. But rightly should have been there:
'57'(42)='73'(49)='34'(39)='47'(35)='73'(34)='34'(26)='42'(86)='26'(84)='65'(81)
removes 5 from r8c2 r5c1.
edit: pls excuse the notation. = in this case is not supposed to imply strong links, just the way the chain works. |
|
Back to top |
|
|
|