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by **eleven** » Sun Jul 30, 2017 10:03 pm

Code: Select all: +-------+-------+-------+ | . 1 . | . . . | 2 3 . | | 2 . . | 4 5 . | . . . | | . . . | . . . | 5 6 . | +-------+-------+-------+ | . 4 . | . . . | . . 7 | | . 5 . | . 2 . | . . 8 | | . . . | . . 8 | . . . | +-------+-------+-------+ | 7 . 3 | . . . | 1 . . | | 4 . 6 | . . . | . . . | | . . . | 7 9 . | . . 6 | +-------+-------+-------+

by **JC Van Hay** » Mon Jul 31, 2017 8:49 am

Code: Select all: +---------------------+--------------------+----------------------+ | 568 1 4578 | 689 678 679 | 2 3 49 | | 2 -6(3) 9 | 4 5 6(3) | 78 78 1 | | 38 37 478 | 12389 1378 12379 | 5 6 49 | +---------------------+--------------------+----------------------+ | 13689 4 128 | 13569 136 13569 | (369) 1259 7 | | 1369 5 (17) | 1369 2 47 | (3469) (149) 8 | | 1369 (67-3) 127 | 13569 47 8 | (3469) 12459 25(3) | +---------------------+--------------------+----------------------+ | 7 289 3 | 2568 468 2456 | 1 24589 25 | | 4 289 6 | 12358 138 1235 | 3789 25789 25(3) | | 15 28 15 | 7 9 24(3) | 48(3) 248 6 | +---------------------+--------------------+----------------------+

Swordfish{3R29C9} -> -{3r6c2}
[3r2c2=3r2c6-3r9c6=3r9c7-(3=469=1)r456c7.r5c8-(1=7=6)r5c3.r6c2]-6r2c2; stte

by **eleven** » Mon Jul 31, 2017 6:31 pm

JC, again you posted basically the same as my solution.
But i am not used to your notation. Please could you describe in words, how to read it ? I tried it below for mine.

Code: Select all: *-------------------------------------------------------------------------* | 568 1 4578 | 689 678 679 | 2 3 49 | | 2 3-6 9 | 4 5 a36 | 78 78 1 | | 38 37 478 | 12389 1378 12379 | 5 6 49 | |-----------------------+-------------------------+-----------------------| | 13689 4 128 | 13569 136 13569 | d369 e1259 7 | | 1369 5 f17 | 1369 2 47 | d3469 e149 8 | | 1369 f367 127 | 13569 47 8 | d3469 e12459 e235 | |-----------------------+-------------------------+-----------------------| | 7 289 3 | 2568 468 2456 | 1 24589 25 | | 4 289 6 | 12358 138 1235 | 3789 25789 235 | | 15 28 15 | 7 9 b234 | c348 248 6 | *-------------------------------------------------------------------------*

(6=3)r2c6-r9c6=r9c7-(3=469)r456c7-(4|6|9)b6p2589=13b6p59.28-(1|3=6)b4p68 => -6r2c2, stte
if r2c6 is not 6, then it is 3,
then no 3 in r9c6, must be in r9c7,
then no 3, but 469 in r456c7,
then in the rest of box 6, marked e, only candidates 1235 are left and r6c9 must be 3 (only cell) and r5c8 must be 1 (only candidate).
[Rem.: the 3 is trivial and the 1 immediately pops up with the triple 469, which leaves 1 in r5c8.]
then no 1 in r5c3, must be 7, and no 3 in r6c2, must be 6.

by **JC Van Hay** » Mon Jul 31, 2017 8:50 pm

Hi eleven,

I suppose you would like an explanation of (3=469=1)r456c7.r5c8 :
1. I often see it written a (3=1)r456.r5c8 or (3=1)b6p1457
2. From left to right, it means (3=4691)r456c7.r5c8
3. From right to left, it means (1=4693)r456c7.r5c8
4. One could also write the ANQ(13469)r456c7.r5c8 as a derived constraint 3r456c7==1r5c8 [as well as 6r456c7==1r5c8]
I wrote a chain mentioning all the candidates, but I could simplify it as
[3r2c2=3r2c6-3r9c6=3r9c7-3r456c7==1r5c8-1r5c3==6r6c2]-6r2c2; stte [taking into account the 3 constraints on the 3s]

Just for comparison, here is your WYSIWYG desription of your chain :

Code: Select all: 6r2c6 3r2c6 3r9c6 3r9c7 3r4c7|6r4c7 9r4c7 | 3r5c7|6r5c7 9r5c7 4r5c7| 3r6c7|6r6c7 9r6c7 4r6c7| 9r5c8 4r5c8 1r5c8 9r4c8 1r4c8|2r4c8 5r4c8| 9r6c8 4r6c8 1r6c8|2r6c8 5r6c8| 2r6c9 5r6c9 3r6c9 1r5c3 7r5c3 3r6c2 7r6c2 6r6c2 -> [6r2c6==6r6c2] => -6r2c2; stte

Note the NT and the NP isolated by the symbols |.
However, you can reduce the number of constraints from 11 to 9 by replacing the 3 cells b6p289=r46c8.r6c9 by the bilocal 3C9.

Code: Select all: 6r2c6 3r2c6 3r9c6 3r9c7 3r4c7|6r4c7 9r4c7 | 3r5c7|6r5c7 9r5c7 4r5c7| 3r6c7|6r6c7 9r6c7 4r6c7| 9r5c8 4r5c8 1r5c8 3r8c9 3r6c9 1r5c3 7r5c3 3r6c2 7r6c2 6r6c2 -> [6r2c6==6r6c2] => -6r2c2; stte

Which is almost the same as my chain : I used the bilocal 3R2 instead of (36)r2c6.
The only difference : I got a cannibalized exclusion 3r6c2 explained by an included sub-chain.

Code: Select all: 3r2c2 3r2c6 3r9c6 3r9c7 3r4c7|6r4c7 9r4c7 | 3r5c7|6r5c7 9r5c7 4r5c7| 3r6c7|6r6c7 9r6c7 4r6c7| 9r5c8 4r5c8 1r5c8 3r8c9 3r6c9 1r5c3 7r5c3 "3r6c2"7r6c2 6r6c2 -> [3r2c2==3r6c9] and [6r2c6==6r6c2] => -{3r6c2, 6r2c2}; stte

Hope this helps,
JC

by **blue** » Tue Aug 01, 2017 6:06 am

Code: Select all: +--------------------+--------------------+----------------------+ | 568 1 4578 | 689 678 679 | 2 3 49 | | 2 -6(3) 9 | 4 5 6(3) | 78 78 1 | | 38 37 478 | 12389 1378 12379 | 5 6 49 | +--------------------+--------------------+----------------------+ | 13689 4 128 | 13569 136 13569 | (369) 1259 7 | | 1369 5 (17) | 1369 2 47 | (3469) (149) 8 | | 1369 (367) 127 | 13569 47 8 | (3469) 12459 25(3) | +--------------------+--------------------+----------------------+ | 7 289 3 | 2568 468 2456 | 1 24589 25 | | 4 289 6 | 12358 138 1235 | 3789 25789 235 | | 15 28 15 | 7 9 24(3) | 48(3) 248 6 | +--------------------+--------------------+----------------------+

Same (basic) logic, different presentation ...

Kraken cell: 367r6c2 => -6r2c2; stte

Code: Select all: 3r6c2 - r6c79 = 3r45c7 -------- || \ 7r6c2 - (7=1)r5c3 - (1=3)b6p147 - 3r9c7 = r9c6 - r2c6 = 3r2c2 - 6r2c2 || / 6r6c2 -------------------------------------------------------

Cheers,
Blue.

by **eleven** » Tue Aug 01, 2017 6:15 am

Thanks JC for the elaborate explanation.

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