Welcome to the world of the unknown. Each day you need to solve <a href="http://www.sudocue.net/xfile.php">two mysteries</a>.<br>Take the X-R-Size or solve the X-Treme problem. Stuck? Found a nice solution? Tell us about it.
emm
Hooked
Posts: 34 Joined: Wed Oct 11, 2006 6:01 pm
Post
by emm » Sun Dec 10, 2006 7:54 pm
Any hints for getting over this hump?
4 or 9 must be in r5c89 but how to figure this out without using brute force?
Code: Select all
+---------------+---------------+------------------+
| 2 3 6 | 5 9 1 | 8 7 4 |
| 49 1 49 | 8 2 7 | 5 6 3 |
| 5 8 7 | 3 6 4 | 9 12 12 |
+---------------+--------------+-------------------+
| 8 45 129 | 6 14 3 | 12 12459 7 |
| 69 246 1239 | 7 8 5 | 36 1249 129 |
| 7 456 13 | 2 14 9 | 36 145 8 |
+---------------+--------------+-------------------+
| 3 69 5 | 1 7 2 | 4 8 69 |
| 46 7 24 | 9 5 8 | 12 3 126 |
| 1 29 8 | 4 3 6 | 7 29 5 |
+---------------+--------------+-------------------+
Ruud
Site Owner
Posts: 601 Joined: Fri Dec 30, 2005 10:21 pm
Post
by Ruud » Sun Dec 10, 2006 9:13 pm
There is an XY-chain that eliminates digit 9 from r5c9:
Code: Select all
(9=6)r7c9-(6=9)r7c2-(9=2)r9c2-(2=4)r8c3-(4=6)r8c1-(6=9)r5c1
if you prefer it in Nice Loop notation:
Code: Select all
[r5c9]-9-[r7c9]-6-[r7c2]-9-[r9c2]-2-[r8c3]-4-[r8c1]-6-[r5c1]-9-[r5c9] => [r5c9]<>9
It's
singles all the way from there.
Ruud
“If the human brain were so simple that we could understand it, we would be so simple that we couldn't.” - Emerson M Pugh
emm
Hooked
Posts: 34 Joined: Wed Oct 11, 2006 6:01 pm
Post
by emm » Mon Dec 11, 2006 8:01 am
Thanks