| View previous topic :: View next topic |
| Author |
Message |
dongrave
Joined: 06 Mar 2014
Posts: 568
|
 Posted: Thu Jun 05, 2014 10:55 pm Post subject: Extremely Difficult Sudolu Puzzle (at least for me) |
 |
|
Hi Marty, Here's the Sudoku that I mentioned in my post earlier today on the 'Daily Sudoku Puzzles' Discussion page. I was able to fill in the first 10 squares but then I came to a complete standstill. I found no way of proceeding using either basic processing or any of the standard advanced techniques (i.e. x-wing, xy-wing, xyz-wing, or URL). Do you see a way to proceed? I spent a long looking after the 1st 10 squares and all that I was able to find was one xyz-wing that eliminated one candidate from one box. Help! I don't see it any way to proceed after the 1st 10 squares!
9 0 4 0 3 0 0 0 5
7 0 0 2 0 0 6 0 0
0 0 0 0 0 5 0 0 0
0 0 3 0 0 1 9 0 6
0 1 0 0 9 0 0 8 0
5 0 9 7 0 0 3 0 0
0 0 0 6 0 0 0 0 0
0 0 2 0 0 8 0 0 7
3 0 0 0 1 0 2 0 9
If you want, I can provide you with the position I that reached but I'm sure that you'll reach it easily enough so I won't bother. As I mentioned in my earlier post today (on the other page), this puzzle was from a recent local newspaper. I have done their puzzles before and none of them have ever been anywhere near this difficult so I suspect that either I'm missing something or they misprinted the puzzle! Thanks, Don. |
|
| Back to top |
|
 |
Marty R.
Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
|
| Posted: Thu Jun 05, 2014 11:46 pm Post subject: |
|
|
| Code: |
+-------+-------+-------+
| 9 . 4 | . 3 . | . . 5 |
| 7 . . | 2 . . | 6 . . |
| . . . | . . 5 | . . . |
+-------+-------+-------+
| . . 3 | . . 1 | 9 . 6 |
| . 1 . | . 9 . | . 8 . |
| 5 . 9 | 7 . . | 3 . . |
+-------+-------+-------+
| . . . | 6 . . | . . . |
| . . 2 | . . 8 | . . 7 |
| 3 . . | . 1 . | 2 . 9 |
+-------+-------+-------+
|
Play this puzzle online at the Daily Sudoku site
Don, you might want to read the article about posting an aligned grid in the Site Help sub-forum if you expect to post more puzzles. |
|
| Back to top |
|
|
Marty R.
Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
|
| Posted: Fri Jun 06, 2014 12:00 am Post subject: |
|
|
I did a very quick attempt at basics online and came up with the following. I'll try doing the puzzle a little later.
| Code: |
+-------------+-------------+-----------------+
| 9 2 4 | 18 3 6 | 178 17 5 |
| 7 35 15 | 2 48 49 | 6 1349 1348 |
| 8 36 16 | 149 7 5 | 14 12349 1234 |
+-------------+-------------+-----------------+
| 2 47 3 | 458 458 1 | 9 57 6 |
| 46 1 67 | 345 9 234 | 57 8 24 |
| 5 8 9 | 7 6 24 | 3 124 124 |
+-------------+-------------+-----------------+
| 14 4579 57 | 6 2 39 | 1458 1345 1348 |
| 146 4569 2 | 39 45 8 | 145 13456 7 |
| 3 456 8 | 45 1 7 | 2 456 9 |
+-------------+-------------+-----------------+
|
Play this puzzle online at the Daily Sudoku site |
|
| Back to top |
|
|
arkietech
Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA
|
| Posted: Fri Jun 06, 2014 12:13 am Post subject: |
|
|
| Code: | There are 2 big almost locked sets one in row 5 and one in row 7 that will remove the candidate 3 in r7c6
*--------------------------------------------------------------------*
| 9 2 4 | 18 3 6 | 178 17 5 |
| 7 35 15 | 2 48 49 | 6 1349 1348 |
| 8 36 16 | 149 7 5 | 14 12349 1234 |
|----------------------+----------------------+----------------------|
| 2 47 3 | 458 458 1 | 9 57 6 |
|a46 1 a67 | 345 9 a234 | 57 8 a24 |
| 5 8 9 | 7 6 24 | 3 124 124 |
|----------------------+----------------------+----------------------|
|b14 4579 b57 | 6 2 9-3 |b1458 b1345 b1348 |
| 146 4569 2 | 39 45 8 | 145 13456 7 |
| 3 456 8 | 45 1 7 | 2 456 9 |
*--------------------------------------------------------------------*
(3=2467)r5c1369-(7=14583)r7c13789 => -3r7c6; ste |
|
|
| Back to top |
|
|
Marty R.
Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
|
| Posted: Fri Jun 06, 2014 1:34 am Post subject: |
|
|
| Quote: | | I found no way of proceeding using either basic processing or any of the standard advanced techniques (i.e. x-wing, xy-wing, xyz-wing, or URL). Do you see a way to proceed? I spent a long looking after the 1st 10 squares and all that I was able to find was one xyz-wing that eliminated one candidate from one box. |
Don,
The grids you see posted by Dan and me have taken basics as far as possible. I can find no X-, XY- or XYZ-Wings or helpful URs. Plus I missed the XYZ-Wing that you played. To complete this puzzle, chains will be required, such as the one that Dan posted.
This is a pretty tough puzzle for a newspaper. |
|
| Back to top |
|
|
dongrave
Joined: 06 Mar 2014
Posts: 568
|
| Posted: Fri Jun 06, 2014 2:01 am Post subject: |
|
|
| Thanks for the input guys! I guess it's time for me to learn some of the more advanced techniques. I think the newspaper must have misprinted this though because I've never had to use wings or chains or cycles to solve any of their puzzles before. Also, thanks for directing me to the help page for posting grids. I'll be sure to do that from now on. I'm pretty sure the poor girl at work will be glad tomorrow to hear what you said about this being an awful difficult puzzle for a newspaper. Thanks again, Don. |
|
| Back to top |
|
|
Pat
Joined: 23 Feb 2010
Posts: 207
|
| Posted: Sun Jun 08, 2014 10:48 am Post subject: |
|
|
| dongrave wrote: | 9.4.3...57..2..6.......5.....3..19.6.1..9..8.5.97..3.....6.......2..8..73...1.2.9 |
maybe r9c1 should've been 6
| Code: |
9 . 4 | . 3 . | . . 5
7 . . | 2 . . | 6 . .
. . . | . . 5 | . . .
-------+-------+------
. . 3 | . . 1 | 9 . 6
. 1 . | . 9 . | . 8 .
5 . 9 | 7 . . | 3 . .
-------+-------+------
. . . | 6 . . | . . .
. . 2 | . . 8 | . . 7
6 . . | . 1 . | 2 . 9
|
~ Pat |
|
| Back to top |
|
|
arkietech
Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA
|
| Posted: Sun Jun 08, 2014 11:14 am Post subject: |
|
|
| Pat wrote: | | maybe r9c1 should've been 6 |
 Thanks Pat! Now it is a nice newspaper puzzle! |
|
| Back to top |
|
|
|
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
