4:47 am
bzikofski
i give up for now. no idea what techniques
6:08 am
tincup
done... good challenge on that one
9:32 am
spellacked
dang, so far two loooong forcing chains dead-ended
9:48 am
bzikofski
forcing chains - that's the technique where checkpoints are very useful
12:22 pm
digondda
http://www.sudokuwiki.org/
2:37 pm
bzikofski
i used some hidden pairs/triples and … it really works! amazing!
7:41 pm
UnikeTheHunter
Two lucky guesses, no greens.
