## difficult puzzle

Post the puzzle or solving technique that's causing you trouble and someone will help

### difficult puzzle

this one can be solved with logic ?
...3.9.7.
8..4.....
1........
2..5..6..
.3.....4.
....1....
5.....8..
....2.1..
...7....9

thanks
cardinal

Posts: 9
Joined: 04 October 2008

It can, but it is tough. My solver needs about 20 Nice Loops (and most of them with group nodes). Forcing Chains will probably shorten it, but still a lot of work will probably remain.
hobiwan
2012 Supporter

Posts: 321
Joined: 16 January 2008
Location: Klagenfurt

......3..
....3.4.6
......2..
...5..6..
.4.......
.7...9...
...19....
126.83...
.........

cardinal

Posts: 9
Joined: 04 October 2008

cardinal wrote:......3..
....3.4.6
......2..
...5..6..
.4.......
.7...9...
...19....
126.83...
.........

I found 21,379,985 solution(s). Last was:
Code: Select all
`  5  1  2  6  7  4  3  8  9  7  8  9  2  3  5  4  1  6  4  6  3  9  1  8  2  7  5  3  9  8  5  4  1  6  2  7  2  4  1  3  6  7  5  9  8  6  7  5  8  2  9  1  4  3  8  5  4  1  9  6  7  3  2  1  2  6  7  8  3  9  5  4  9  3  7  4  5  2  8  6  1`

Regards,

Mike Metcalf

m_b_metcalf
2017 Supporter

Posts: 9466
Joined: 15 May 2006
Location: Berlin

m_b_metcalf wrote:
cardinal wrote:
Code: Select all
`......3......3.4.6......2.....5..6...4........7...9......19....126.83............`

I found 21,379,985 solution(s).

did you stop counting?
my solver found 193,792,242 solutions total
gsf
2014 Supporter

Posts: 7306
Joined: 21 September 2005
Location: NJ USA

gsf wrote:
m_b_metcalf wrote:I found 21,379,985 solution(s).

did you stop counting?
my solver found 193,792,242 solutions total

I've done a quick regression test on my latest solver and it counts some old invalid puzzles correctly. Could I appeal to someone else to perform this check before I spend more time on it?

Thanks,

Mike Metcalf

m_b_metcalf
2017 Supporter

Posts: 9466
Joined: 15 May 2006
Location: Berlin

Unfortunately My solver count stops at 3000, it is too slow to count beyond 10,000 ...

Have you tried on the Programmers forum ?!!!

tarek

Posts: 2807
Joined: 05 January 2006

m_b_metcalf wrote:
gsf wrote:
m_b_metcalf wrote:I found 21,379,985 solution(s).

did you stop counting?
my solver found 193,792,242 solutions total

I've done a quick regression test on my latest solver and it counts some old invalid puzzles correctly. Could I appeal to someone else to perform this check before I spend more time on it?

do you have any tests for human operators?
my invalid puzzle cataloging is apparently deficient

for this invalid puzzle (which is the one you counted)
Code: Select all
`......3......3.4.6......2.....5..6...4........7...9......19....126.83............`

I get 21,379,985 solutions -- good, we match

for this puzzle (same poster on programmer's forum, different puzzle)
Code: Select all
`...6...7....4.5......7.....9.....5.....5.7.......4....65....417.4................ `

I get 193,792,242 solutions
gsf
2014 Supporter

Posts: 7306
Joined: 21 September 2005
Location: NJ USA

gsf wrote:I get 193,792,242 solutions

Me too ("For this relief much thanks;").

Regards,

Mike Metcalf

m_b_metcalf
2017 Supporter

Posts: 9466
Joined: 15 May 2006
Location: Berlin

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