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Website · by **denis_berthier** » Mon Apr 26, 2021 4:16 am

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Code: Select all: +-------+-------+-------+ ! 1 . . ! . . 6 ! . . 9 ! ! . . . ! . . . ! . . . ! ! . 8 . ! 1 . . ! 5 6 . ! +-------+-------+-------+ ! . 3 . ! 6 . . ! 8 . 1 ! ! . . . ! . . . ! . . 7 ! ! . . . ! . . 8 ! 2 4 6 ! +-------+-------+-------+ ! . 4 . ! 9 . . ! . 2 . ! ! 5 6 . ! 8 4 1 ! . . . ! ! . . 7 ! . . 3 ! . . . ! +-------+-------+-------+ 1....6..9..........8.1..56..3.6..8.1........7.....8246.4.9...2.56.841.....7..3... 26 givens; SER = 3.8

by **RSW** » Mon Apr 26, 2021 5:03 am

Code: Select all: +-------------------+--------------------+---------------+ | 1 257 345 | 23457 23578 6 | 347 378 9 | | 234679 2579 34569 | 23457 235789 24579 | 1347 1378 248 | |*23479 8 349 | 1 *2379 *2479 | 5 6 24 | +-------------------+--------------------+---------------+ |*2479 3 459 | 6 *2579 *2579 | 8 59 1 | | 68 1259 68 | 245 1259 2459 | 39 359 7 | | 79 1579 159 | 357 13579 8 | 2 4 6 | +-------------------+--------------------+---------------+ |*38 4 138 | 9 *567 *57 | 16 2 58 | | 5 6 2 | 8 4 1 | 79 79 3 | | 89 19 7 | 25 256 3 | 46 18 45 | +-------------------+--------------------+---------------+

Swordfish: (7)r347c156 => -7r26c1 -7r126c5 -7r2c6; stte

by **DEFISE** » Mon Apr 26, 2021 10:27 am

I have not implemented Swordfish and Jellyfish.
So for me this puzzle is in W7 but also in g-W2 (without subsets in basics, only one g-Whip needed).
Amazing !

by **rjamil** » Mon Apr 26, 2021 12:48 pm

RSW wrote:
Code: Select all
+-------------------+--------------------+---------------+ | 1 257 345 | 23457 23578 6 | 347 378 9 | | 234679 2579 34569 | 23457 235789 24579 | 1347 1378 248 | |*23479 8 349 | 1 *2379 *2479 | 5 6 24 | +-------------------+--------------------+---------------+ |*2479 3 459 | 6 *2579 *2579 | 8 59 1 | | 68 1259 68 | 245 1259 2459 | 39 359 7 | | 79 1579 159 | 357 13579 8 | 2 4 6 | +-------------------+--------------------+---------------+ |*38 4 138 | 9 *567 *57 | 16 2 58 | | 5 6 2 | 8 4 1 | 79 79 3 | | 89 19 7 | 25 256 3 | 46 18 45 | +-------------------+--------------------+---------------+

Swordfish: (7)r347c156 => -7r26c1 -7r126c5 -7r2c6; stte

OR

Code: Select all: +----------------------+----------------------+-----------------+ | 1 *257 345 |*23457 2358-7 6 |*347 *378 9 | | 23469-7 *2579 34569 |*23457 23589-7 2459-7|*1347 *1378 248 | | 23479 8 349 | 1 2379 2479 | 5 6 24 | +----------------------+----------------------+-----------------+ | 2479 3 459 | 6 2579 2579 | 8 59 1 | | 68 1259 68 | 245 1259 2459 | 39 359 7 | | 9-7 *1579 159 |*357 1359-7 8 | 2 4 6 | +----------------------+----------------------+-----------------+ | 38 4 138 | 9 567 57 | 16 2 58 | | 5 6 2 | 8 4 1 |*79 *79 3 | | 89 19 7 | 25 256 3 | 46 18 45 | +----------------------+----------------------+-----------------+

Jelly Fish: Column wise 7 @ r1268c2478; stte

OR

Code: Select all: +----------------------+------------------------+-----------------+ | 1 257 345 | 2345(7) 2358-7 6 | 347 378 9 | | 23469-7 2579 34569 | 2345(7) 23589-7 2459-7 | 1347 1378 248 | | 234(7)9 8 349 | 1 23(7)9 24(7)9 | 5 6 24 | +----------------------+------------------------+-----------------+ | 24[7]9 3 459 | 6 2579 2579 | 8 59 1 | | 68 1259 68 | 245 1259 2459 | 39 359 7 | | (9-7) 15[7]9 159 | 35(7) 1359-7 8 | 2 4 6 | +----------------------+------------------------+-----------------+ | 38 4 138 | 9 567 57 | 16 2 58 | | 5 6 2 | 8 4 1 | 79 79 3 | | 89 19 7 | 25 256 3 | 46 18 45 | +----------------------+------------------------+-----------------+

Grouped 2-String Kite+ERI Ring: SL 7 @ r3c156 and 7 @ r126c4 ERI 7 @ b4r6c1 => -7 @ r1c5 r2c156 r6c15; stte

R. Jamil

by **pjb** » Mon Apr 26, 2021 12:52 pm

Code: Select all: 1 f257 345 |c23457 2358-7 6 | 347 378 9 23469-7 f2579 34569 |c23457 23589-7 2459-7 | 1347 1378 248 a23479 8 349 | 1 b2379 b2479 | 5 6 24 -------------------------+-----------------------+--------------------- 2479 3 459 | 6 2579 2579 | 8 59 1 68 1259 68 | 245 1259 2459 | 39 359 7 9-7 e1579 159 |d357 1359-7 8 | 2 4 6 -------------------------+-----------------------+--------------------- 38 4 138 | 9 567 57 | 16 2 58 5 6 2 | 8 4 1 | 79 79 3 89 19 7 | 25 256 3 | 46 18 45

Grouped continuous chain: (7)r3c1 = r3c56 - r12c4 = r6c4 - r6c2 = r12c2 - loop => -7 r1c5, -7 r2c156, -7 r6c15; stte

Phil

Website · by **denis_berthier** » Mon Apr 26, 2021 2:43 pm

DEFISE wrote:I have not implemented Swordfish and Jellyfish.
So for me this puzzle is in W7 but also in g-W2 (without subsets in basics, only one g-Whip needed).
Amazing !

Yes, I chose it from my large controlled-bias collection as an extremely rare case where:
- the SER is small;
- the W and gW ratings are largely different;
- AND the W and S+W ratings are also largely different.
Most of the time, W = S+W = gW = S+gW; and when this is not true, the difference is rarely greater than 1.

Code: Select all: Resolution state after Singles: +----------------------+----------------------+----------------------+ ! 1 257 345 ! 23457 23578 6 ! 347 378 9 ! ! 234679 2579 34569 ! 23457 235789 24579 ! 1347 1378 248 ! ! 23479 8 349 ! 1 2379 2479 ! 5 6 24 ! +----------------------+----------------------+----------------------+ ! 2479 3 459 ! 6 2579 24579 ! 8 59 1 ! ! 24689 1259 145689 ! 2345 12359 2459 ! 39 359 7 ! ! 79 1579 159 ! 357 13579 8 ! 2 4 6 ! +----------------------+----------------------+----------------------+ ! 38 4 138 ! 9 567 57 ! 167 2 58 ! ! 5 6 2 ! 8 4 1 ! 79 79 3 ! ! 89 19 7 ! 25 256 3 ! 1469 1589 458 ! +----------------------+----------------------+----------------------+ 191 candidates, 1155 csp-links and 1155 links. Density = 6.37%

whip[1]: c9n5{r9 .} ==> r9c8 ≠ 5
whip[1]: r8n9{c8 .} ==> r9c8 ≠ 9, r9c7 ≠ 9
whip[1]: r8n7{c8 .} ==> r7c7 ≠ 7
whip[1]: r6n3{c5 .} ==> r5c5 ≠ 3, r5c4 ≠ 3

Code: Select all: Resolution state after Singles and whips[1]: +----------------------+----------------------+----------------------+ ! 1 257 345 ! 23457 23578 6 ! 347 378 9 ! ! 234679 2579 34569 ! 23457 235789 24579 ! 1347 1378 248 ! ! 23479 8 349 ! 1 2379 2479 ! 5 6 24 ! +----------------------+----------------------+----------------------+ ! 2479 3 459 ! 6 2579 24579 ! 8 59 1 ! ! 24689 1259 145689 ! 245 1259 2459 ! 39 359 7 ! ! 79 1579 159 ! 357 13579 8 ! 2 4 6 ! +----------------------+----------------------+----------------------+ ! 38 4 138 ! 9 567 57 ! 16 2 58 ! ! 5 6 2 ! 8 4 1 ! 79 79 3 ! ! 89 19 7 ! 25 256 3 ! 146 18 458 ! +----------------------+----------------------+----------------------+

1) Solution in Subsets[3] (even if whips are active, they don't appear - except the whips[1]):

Code: Select all: hidden-pairs-in-a-row: r5{n6 n8}{c1 c3} ==> r5c3 ≠ 9, r5c3 ≠ 5, r5c3 ≠ 4, r5c3 ≠ 1, r5c1 ≠ 9, r5c1 ≠ 4, r5c1 ≠ 2 whip[1]: r5n4{c6 .} ==> r4c6 ≠ 4 naked-triplets-in-a-row: r9{c1 c2 c8}{n8 n9 n1} ==> r9c9 ≠ 8, r9c7 ≠ 1 swordfish-in-rows: n7{r3 r4 r7}{c6 c1 c5} ==> r6c5 ≠ 7, r6c1 ≠ 7, r2c6 ≠ 7, r2c5 ≠ 7, r2c1 ≠ 7, r1c5 ≠ 7 stte

2) solution using a single g-whip[2], immediately after the Singles (no whip[1] needed)

Code: Select all: g-whip[2]: r3n7{c1 c456} - c4n7{r1 .} ==> r6c1 ≠ 7 stte

A good example for learning g-whips.

3) solution in W7 with no Subset activated. Not interesting in itself.

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