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[ArkieTech]

Code: Select all

 *-----------*
 |..1|..2|3..|
 |.9.|...|.1.|
 |8..|6..|..7|
 |---+---+---|
 |..3|1..|..8|
 |...|...|...|
 |6..|..7|5..|
 |---+---+---|
 |7..|..4|..6|
 |.2.|...|.9.|
 |..5|3..|1..|
 *-----------*


Play/Print this puzzle online

[tlanglet]

Code after basics:

Code: Select all

 *--------------------------------------------------------------------------------------*
 | 45       67       1        | 45789    45789    2        | 3        68       459      |
 | 2345     9        67       | 4578     34578    358      | 68       1        245      |
 | 8        345      24       | 6        13459    1359     | 249      245      7        |
 |----------------------------+----------------------------+----------------------------|
 | 2459     457      3        | 1        24569    569      | 24679    2467     8        |
 | 12459    14578    24789    | 24589    2345689  35689    | 24679    23467    12349    |
 | 6        148      2489     | 2489     23489    7        | 5        234      12349    |
 |----------------------------+----------------------------+----------------------------|
 | 7        13       89       | 2589     12589    4        | 28       35       6        |
 | 13       2        468      | 578      15678    1568     | 478      9        35       |
 | 49       468      5        | 3        26789    689      | 1        2478     24       |
 *--------------------------------------------------------------------------------------*


I was chasing an AXY-wing when I found this solution. It has two steps that require memory, marked by *.

(2=4)*r9c9-r9c12=(4-6)r8c3=(6=8)r2c37-(48=7)*r8c7-r8c45=(7-2)r9c5=2*r9c8 => r9c5,r7c7<>2

An alternate view of this logic is

ANT(248=7)r7c7,r9c9,r8c7-r8c45=(7-2)r9c5=2r9c89-(2=8)r7c7 => r9c8<>8

[ArkieTech]

Code: Select all

 *--------------------------------------------------------------------------------------*
 | 45       67       1        | 45789    45789    2        | 3        68       459      |
 | 2345     9        67       | 4578     34578    358      | 68       1        245      |
 | 8        345      24       | 6        13459    1359     | 249      245      7        |
 |----------------------------+----------------------------+----------------------------|
 | 2459     457      3        | 1        24569    569      | 24679    2467     8        |
 | 12459    14578    24789    | 24589    2345689  35689    | 24679    23467    12349    |
 | 6        148      2489     | 2489     23489    7        | 5        234      12349    |
 |----------------------------+----------------------------+----------------------------|
 | 7        13       89       |b2589    b12589    4        |a28       35       6        |
 | 13       2        468      | 578      15678    1568     | 478      9        35       |
 | 49       468      5        | 3       c26789    689      | 1       d247-8    24       |
 *--------------------------------------------------------------------------------------*
h-wing
(8=2)r7c7-r7c45=(2-7)r9c5=7r9c8 => -8r9c8; stte


[Leren]

Hi Dan,

A question on notation - should the last step of your H-Wing read =(7-8)r9c8 ?

Leren

[ArkieTech]

Hi Dan,

A question on notation - should the last step of your H-Wing read =(7-8)r9c8 ?

Leren

My understanding is the last step in an eureka notation should not be a weak link. I do not see where it is needed at all.

[Marty R.]

I stared at this grid for hours without finding anything quick. I ended up using an XY-Loop, three W-Wings (don't know if all were needed) and an XY-Wing.

h-wing
(8=2)r7c7-r7c45=(2-7)r9c5-7r9c8 = -8r9c8; stte

OK, bear with me since I'm a notation newbie. A term like (2-7) was something I first saw as part of an M-Wing and in English it meant "if the cell is not 7", which, of course, is how you'd say the end of an M-Wing. So if it has that same meaning, then the next term would say =7r9c8. As it stands, you have consecutive weak inference symbols which I thought was a no-no.

[ArkieTech]

I stared at this grid for hours without finding anything quick. I ended up using an XY-Loop, three W-Wings (don't know if all were needed) and an XY-Wing.

h-wing
(8=2)r7c7-r7c45=(2-7)r9c5-7r9c8 = -8r9c8; stte

OK, bear with me since I'm a notation newbie. A term like (2-7) was something I first saw as part of an M-Wing and in English it meant "if the cell is not 7", which, of course, is how you'd say the end of an M-Wing. So if it has that same meaning, then the next term would say =7r9c8. As it stands, you have consecutive weak inference symbols which I thought was a no-no.

Thanks Marty! I have edited notation to (8=2)r7c7-r7c45=(2-7)r9c5=7r9c8 => -8r9c8; stte

No wonder folks where having trouble with this. I must have been asleep. It is like an m-wing only with three digits 827 instead of two.