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 

December 25, Happy Christmas!

 
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Daily Sudoku puzzles
View previous topic :: View next topic  
Author Message
Glassman



Joined: 21 Oct 2005
Posts: 50
Location: England

PostPosted: Sun Dec 25, 2005 7:35 am    Post subject: December 25, Happy Christmas! Reply with quote



Happy Christmas, everyone.

Sam Thanks for today's 9x9 puzzle. You seem to have saved one of your best for Christmas day. A particularly fine puzzle for sticklers (whether or not fingers are utilised).

It took me considerable time to figure out the trickier bits

Thanks for all your time and effort,

Glassman

Back to top
View user's profile Send private message
bev
Guest





PostPosted: Mon Dec 26, 2005 2:13 pm    Post subject: Reply with quote

Ok smarty pants, then maybe you can help me. I got stuck as follows:
x367x8xxx
7xxxxx9xx
5xxxxx37x
xxx126754
xx48x72xx
x7xx438xx
x17xxxx92
xx9xxxxxx
xxx6x948x

I went for the hint and it gave me a 9 in row 1, column 5. I can't find a reason why that has to be.

Any ideas?
Back to top
Guest






PostPosted: Mon Dec 26, 2005 7:59 pm    Post subject: Reply with quote

I think he was referring to yesterdays puzzle. As far as todays goes,I have r1c5 narrowed down to either 5 or 9. Ill take your hint and finish it off

Heres what I have so far:
x367x8xxx
7xxx3x9x6
5xxx6x378
xxx126754
xx48x72xx
x7xx438xx
x17x8xx92
xx9x72xxx
xxx619487

bev wrote:
Ok smarty pants, then maybe you can help me. I got stuck as follows:
x367x8xxx
7xxxxx9xx
5xxxxx37x
xxx126754
xx48x72xx
x7xx438xx
x17xxxx92
xx9xxxxxx
xxx6x948x

I went for the hint and it gave me a 9 in row 1, column 5. I can't find a reason why that has to be.

Any ideas?
Back to top
Guest






PostPosted: Mon Dec 26, 2005 8:15 pm    Post subject: Reply with quote

Solution:




























436798125
728531946
591462378
983126754
164857239
275943861
617384592
849275613
352619487
Back to top
someone_somewhere



Joined: 07 Aug 2005
Posts: 275
Location: Munich

PostPosted: Tue Dec 27, 2005 6:49 am    Post subject: Reply with quote

Hi,

I will try to help.
Starting from:
Code:
  . 3 6 7 . 8 . . .
  7 . . . . . 9 . .
  5 . . . . . 3 7 .
  . . . 1 2 6 7 5 4
  . . 4 8 . 7 2 . .
  . 7 . . 4 3 8 . .
  . 1 7 . . . . 9 2
  . . 9 . . . . . .
  . . . 6 . 9 4 8 .

follow the path:
Code:
 3 not in r5c1, it is in r4c1 or r4c3 (Row on 3x3 Block interaction)

 9 not in r5c1, not in r5c2, not in r6c1, it is in r4c1 or r4c2 (Row on 3x3 Block interaction)

 2 not in r8c1, not in r8c2, it is in r9c1 or r9c2 or r9c3 (Row on 3x3 Block interaction)

 6 not in r8c8, not in r8c9, it is in r7c7 or r8c7 (Column on 3x3 Block interaction)

 1 not in r1c1, 1 not in r1c8, 9 not in r1c1, Hidden Pair 2 4 in r1c1 and r1c8 (in Row)

 1 not in r1c5, 5 not in r1c5, Nacked Pair 1 5 in r1c7 and r1c9 (same Row)

 3 not in r9c5, 3 not in r9c9, 5 not in r9c5, 5 not in r9c9, Hidden Pair 1 7 in r9c5 and r9c9 (in Row)

and now we can deduce:
9 in r1c5 - Sole Candidate

see u,
Back to top
View user's profile Send private message
Bev
Guest





PostPosted: Tue Dec 27, 2005 4:39 pm    Post subject: Reply with quote

I'm starting to feel really stupid here. I can't follow any of your "not"s - for example, WHY can't there be a 3 in row 5 column 1??? There's no 3 in column 1, no 3 in row 5 and no 3 in that 3X3 block. Likewise for the other ones you have said "not in" about. Is there some other logic I am totally missing?
Back to top
Bev
Guest





PostPosted: Tue Dec 27, 2005 9:33 pm    Post subject: Reply with quote

OK now I'm seeing the additional logic steps I hadn't thought about before. Got this Xmas puzzle done anyway, and my first very hard one. Still have a lot to learn when it comes to the hidden pairs and triplets though - any rules of thumb on those?
Back to top
Display posts from previous:   
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Daily Sudoku 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