Shapes to remember (SDK level)

kvasir · Post by **kvasir** » Sun Aug 15, 2021 4:37 am

Click Here To Show Diagram Code: [go]$$Wc White to play $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . O O X | $$ | . . . X . . . . . . . . . O O O O X . | $$ | . . O . . X . . X . . . . O . O X X X | $$ | . . . O . . . . . , O O O . . , O X . | $$ | . . . . . . . . . . O . . . . O X X X | $$ | . . O . . . . . . X X O O . . O O O X | $$ | . . . . . . . . . X O O O O . . . O O | $$ | . . . . . . . . . . X O O . . O O O . | $$ | . . . . . . . . . . X . O O O O O O X | $$ | . . . , . . . . . , . X X O O X X O X | $$ | . . O . . . . . X . . . O O X . X X . | $$ | . . . . . . X . O X . . X X . X . . . | $$ | . . . . . X . . O . X . . . . . . . . | $$ | . O . O . 3 . . . . . X . . . . . . . | $$ | . O X O . X . O O . O . . X . X . . . | $$ | . X O O . . X X 2 , O X X O X , . . . | $$ | X . X O . O . 1 X . O X O O O X . . . | $$ | . X X X O . . O X X O O O O X . X . . | $$ | . . . . . . . . . . . . . X . X . . . | $$ ---------------------------------------[/go]

I am not confident about going directly to 3 but black is unlikely to play 2

jlt · Post by **jlt** » Thu Aug 19, 2021 12:46 am

Position #56: how to respond to the crosscut?

Click Here To Show Diagram Code: [go]$$Bc Black to play $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . X . . X . . . . O O X . . . | $$ | . . W X . . . . . , . . O X . X . . . | $$ | . . X O . . O . . . . . O X . . . . . | $$ | . . . . . . . . O . . . . X . . . . . | $$ | . . . X . . O . . . . . . . . O . . . | $$ | . . . . . . . . X . . . . . . . . . . | $$ | . . . X . . O . . . . . . . . . . . . | $$ | . . . , . . . . X , . . . . . , . . . | $$ | . . X . . . O . . . . . . . . . . . . | $$ | . . . O . O . X . . . . . . . . . . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . O . . X . . . . . . . . . . . | $$ | . . X . . . . . X . . . . . . . . . . | $$ | . . . X X X X X O O . . . . . , O . . | $$ | . . . O . . O O . . . . . . . . . . . | $$ | . . . . O . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Answer

jlt · Post by **jlt** » Mon Aug 23, 2021 9:37 am

Position #57, another shape move, from a Fox 2d game. White to play.

Click Here To Show Diagram Code: [go]$$Wc White to play $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O X X X . . . X X O . . . . . . | $$ | . . . O O O . X . . O . O . O X . . . | $$ | . . O , . . . . . , O . . . O , X O . | $$ | . . O X . . . X . . . . . . . O O . O | $$ | . . X X . . . . . . . . . . . O X O O | $$ | . . . . . . . O . . O . . O O X X X O | $$ | . . . . . . . . . . X O O X X . O X O | $$ | . . . . . . . . . O O X X . X O . . X | $$ | . . . X . . . . . , . . . X . X X X . | $$ | . . . . . . . . . . O X X . X . . . . | $$ | . . . . . . . . . . X O X . . . O . . | $$ | . . X . X . . . . . X O . . X . . . . | $$ | . . . . . . . . O . X O . O O O . . . | $$ | . . . X O . . . . O X O . X . . . . . | $$ | . . . X O . . . O X X O . . O O O O O | $$ | . . X O O . . . O X . O . X . X O X X | $$ | . . X X O . . . O X . . X . . X X . . | $$ | . . . . . . . . . X . . . . . . . X . | $$ ---------------------------------------[/go]

Answer:

Click Here To Show Diagram Code: [go]$$Wc The marked stones are captured $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O X X X . 1 3 B B O . . . . . . | $$ | . . . O O O . X 2 . O . O . O X . . . | $$ | . . O , . . . . . , O . . . O , X O . | $$ | . . O X . . . X . . . . . . . O O . O | $$ | . . X X . . . . . . . . . . . O X O O | $$ | . . . . . . . O . . O . . O O X X X O | $$ | . . . . . . . . . . X O O X X . O X O | $$ | . . . . . . . . . O O X X . X O . . X | $$ | . . . X . . . . . , . . . X . X X X . | $$ | . . . . . . . . . . O X X . X . . . . | $$ | . . . . . . . . . . X O X . . . O . . | $$ | . . X . X . . . . . X O . . X . . . . | $$ | . . . . . . . . O . X O . O O O . . . | $$ | . . . X O . . . . O X O . X . . . . . | $$ | . . . X O . . . O X X O . . O O O O O | $$ | . . X O O . . . O X . O . X . X O X X | $$ | . . X X O . . . O X . . X . . X X . . | $$ | . . . . . . . . . X . . . . . . . X . | $$ ---------------------------------------[/go]

Black can't save the two stones, the following diagram is horrible for Black:

Click Here To Show Diagram Code: [go]$$Wc horrible for Black $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O X X X . 1 2 X X O . . . . . . | $$ | . . . O O O . X 3 4 O . O . O X . . . | $$ | . . O , . . . . 5 6 O . . . O , X O . | $$ | . . O X . . . X 7 . . . . . . O O . O | $$ | . . X X . . . . . . . . . . . O X O O | $$ | . . . . . . . O . . O . . O O X X X O | $$ | . . . . . . . . . . X O O X X . O X O | $$ | . . . . . . . . . O O X X . X O . . X | $$ | . . . X . . . . . , . . . X . X X X . | $$ | . . . . . . . . . . O X X . X . . . . | $$ | . . . . . . . . . . X O X . . . O . . | $$ | . . X . X . . . . . X O . . X . . . . | $$ | . . . . . . . . O . X O . O O O . . . | $$ | . . . X O . . . . O X O . X . . . . . | $$ | . . . X O . . . O X X O . . O O O O O | $$ | . . X O O . . . O X . O . X . X O X X | $$ | . . X X O . . . O X . . X . . X X . . | $$ | . . . . . . . . . X . . . . . . . X . | $$ ---------------------------------------[/go]

Position #58: White to play.

Click Here To Show Diagram Code: [go]$$Wc White to play $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . X . . . . . . . . O X X . . . . | $$ | . . O . . X . . . . O . . O X . . . . | $$ | . . . O . . . . X , . . . O . X . . . | $$ | . . . . . . . . . . X . . . . . . . . | $$ | . . O . . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . O . O X . . | $$ | . . O X . . . . . . . . . . . . . . . | $$ | . X O O . . . . . . O . . . . . . . . | $$ | . X X O . . . . . , . . O . O , O . . | $$ | . . O X . . . . . X . X . . . . . . . | $$ | . . X . . . . . . O . . X . X . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X X . X . . . . . . . . . . . . . | $$ | . . O . . . . . . . . . . . . . O . . | $$ | . . . O . . . . . , O O O O O O X O . | $$ | . . . . . O . . O O X X O X X X X X . | $$ | . . . . . . . . O X X . X . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Farodin · Post by **Farodin** » Sat Sep 18, 2021 4:32 am

I counted black to be slightly ahead in this position, so white has to do something active.

Click Here To Show Diagram Code: [go]$$Wc Black resists $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . X . . . 5 3 4 . . O X X . . . . | $$ | . . O . . X . 1 2 6 O . . O X . . . . | $$ | . . . O . . . 7 X , . . . O . X . . . | $$ | . . . . . . . . . . X . . . . . . . . | $$ | . . O . . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . O . O X . . | $$ | . . O X . . . . . . . . . . . . . . . | $$ | . X O O . . . . . . O . . . . . . . . | $$ | . X X O . . . . . , . . O . O , O . . | $$ | . . O X . . . . . X . X . . . . . . . | $$ | . . X . . . . . . O . . X . X . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X X . X . . . . . . . . . . . . . | $$ | . . O . . . . . . . . . . . . . O . . | $$ | . . . O . . . . . , O O O O O O X O . | $$ | . . . . . O . . O O X X O X X X X X . | $$ | . . . . . . . . O X X . X . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

I think white should jump in at

, breaking the large knight's move. If black resists with

and so on, black suddenly finds himself with 3 weak groups on the board (top left, top center, right side), while white on the top right looks stable enough to not be a big burden in the upcoming fight.

Click Here To Show Diagram Code: [go]$$Wc Black has to pull back $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 5 X . . . . . . . . O X X . . . . | $$ | . . O . . X . 1 3 . O . . O X . . . . | $$ | . . . O . . 4 2 X , . . . O . X . . . | $$ | . . . . . . . . . . X . . . . . . . . | $$ | . . O . . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . O . O X . . | $$ | . . O X . . . . . . . . . . . . . . . | $$ | . X O O . . . . . . O . . . . . . . . | $$ | . X X O . . . . . , . . O . O , O . . | $$ | . . O X . . . . . X . X . . . . . . . | $$ | . . X . . . . . . O . . X . X . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X X . X . . . . . . . . . . . . . | $$ | . . O . . . . . . . . . . . . . O . . | $$ | . . . O . . . . . , O O O O O O X O . | $$ | . . . . . O . . O O X X O X X X X X . | $$ | . . . . . . . . O X X . X . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

So I think black can't resist, and has to pull back at

to connect his stones. White does likewise with

. After this, I think white can even afford to play at

immediately, since the black group is now unsettled. After this sequence the territory balance swings back into white's favour.

jlt · Post by **jlt** » Sat Sep 18, 2021 1:03 pm

Farodin found the blue move.

Position #59, White to play. From a game I played in my club. How to respond to the last move?

Click Here To Show Diagram Code: [go]$$Wc White to play $$ --------------------------------------- $$ | . . . X . . . . . . . . . . X . . . . | $$ | . . X . X O . . . . . . O X . . . . . | $$ | . . X X O X O . . . . O . O X X X . . | $$ | . . O O O . . . . , . . . O X O O . . | $$ | . . . . . . . . . . . . . X O . . . . | $$ | . . . . . . . . . . . . . . O . B . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . X . . . . . . . . . . . O O . . | $$ | . . . . . . . . . . . . . . . X X O . | $$ | . . . , . . . . . , . . . . . X O O . | $$ | . . . X . . . . . . . . . X . . X O . | $$ | . . . . . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Answer:

Do not connect passively at Q15!

Click Here To Show Diagram Code: [go]$$Wc Answer $$ --------------------------------------- $$ | . . . X . . . . . . . . . . X . . . . | $$ | . . X . X O . . . . . . O X . . . 2 . | $$ | . . X X O X O . . . . O . O X X X 1 . | $$ | . . O O O . . . . , . . . O X O O 3 . | $$ | . . . . . . . . . . . . . X O . . . . | $$ | . . . . . . . . . . . . . . O . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . X . . . . . . . . . . . O O . . | $$ | . . . . . . . . . . . . . . . X X O . | $$ | . . . , . . . . . , . . . . . X O O . | $$ | . . . X . . . . . . . . . X . . X O . | $$ | . . . . . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Later if Black wants to pull out the peeping stone, the local continuation looks like this

Click Here To Show Diagram Code: [go]$$Wc Continuation $$ --------------------------------------- $$ | . . . X . . . . . . . . . . X . . 6 . | $$ | . . X . X O . . . . . . O X . a . X 5 | $$ | . . X X O X O . . . . O . O X X X O . | $$ | . . O O O . . . . , . . . O X O O O . | $$ | . . . . . . . . . . . . . X O . . . . | $$ | . . . . . . . . . . . . . . O 7 X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . 4 . . | $$ | . . . . . . . . . . . . . . . . . . . |[/go]

Black will probably need to add a move at "a" later.

If instead of

Black lives in the corner immediately, a local continuation like this may be played.

Click Here To Show Diagram Code: [go]$$Wc $$ --------------------------------------- $$ | . . . X . . . . . . . . . . X . . . . | $$ | . . X . X O . . . . . . O X . . . X 4 | $$ | . . X X O X O . . . . O . O X X X O . | $$ | . . O O O . . . . , . . . O X O O O . | $$ | . . . . . . . . . . . . . X O . . . . | $$ | . . . . . . . . . . . . . . O . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . 5 . . . | $$ | . . . . . . . . . . . . . . . . . . . |[/go]

jlt · Post by **jlt** » Mon Jan 03, 2022 6:04 am

Position #60, Black to play. A rather basic shape, how could I miss it?

Click Here To Show Diagram Code: [go]$$Bc $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . X . . . | $$ | . . . O . . . O . . . . . O . . . . . | $$ | . . . , O . . . . , . . . . . X . . . | $$ | . . X . . . . . . . . . . O . . . . . | $$ | . . . . . . . . . . . . . . . X . . . | $$ | . . . . . . . . . . . . . O . . . . . | $$ | . . X . . . . . . . . . . . . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . O O X X . . , . . . | $$ | . . . . . . . . O . X O X . . . . . . | $$ | . . . . . . . X O . X O . . . . . . . | $$ | . . . . . . . . X . X . O . X . . . . | $$ | . X . . . . . . . . . . . O O X X . . | $$ | . . . O . . . . O . X . O . . O X . . | $$ | . . X O . . . . . , . . . . . O X . . | $$ | . . X O . . . . O . X . O . O X . . . | $$ | . . . . . . . . . . . . . . O X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

dhu163 · Post by **dhu163** » Mon Jan 03, 2022 7:47 am

Knotwilg · Post by **Knotwilg** » Mon Jan 03, 2022 9:09 am

Read the same as dhu and now wondering about this:

but indeed, Hu's suggestion may be best

An amusing after thought with KataGo:

jlt · Post by **jlt** » Mon Jan 03, 2022 9:59 am

Thanks for your remarks, you indeed found the same first move as Katago:

Click Here To Show Diagram Code: [go]$$Bc $$ | . . . . . . . . . . . . . . . X . . . | $$ | . . . . . . . . . . . . . O . . . . . | $$ | . . X . . . . . . . . . . . . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . W W X X . . , . . . | $$ | . . . . . . . . W . X O X . . . . . . | $$ | . . . . . . . X W . X O . . . . . . . | $$ | . . . . . . . a X . X . O . X . . . . | $$ | . X . . . . 3 . 1 . . . . O O X X . . | $$ | . . . W . . . 2 O . X . O . . O X . . | $$ | . . X W . . . . . , . . . . . O X . . | $$ | . . X W . . . . O . B . O . O X . . . | $$ | . . . . . . . . . . . . . . O X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

(If

is at a then

is at

making miai of capturing one stone or another.)

Katago doesn't seem to care much about the marked black stone. I don't understand its variations as they are rather complicated but it seems it wants to make a strong central group in order to attack either marked white group. Here is for instance a simple variation which is considered as good for Black:

Click Here To Show Diagram Code: [go]$$Bc $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . X . . . | $$ | . . . O . . . O . . . . . O . . . . . | $$ | . . . , O . . . . , . . . . . X . . . | $$ | . . X . . . . . . . . . . O . . . . . | $$ | . . . . . . . . . . . . . . . X . . . | $$ | . . . . . . . . . . . . . O . . . . . | $$ | . . X . . . . . . . . . . . . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . O O X X . . , . . . | $$ | . . . . . . . . O . X O X . . . . . . | $$ | . . . . . . . X O . X O . . . . . . . | $$ | . . . . . . . . X . X . O . X . . . . | $$ | . X . . . . . . 1 3 . . . O O X X . . | $$ | . . . O . . . 9 O 2 X 7 O . . O X . . | $$ | . . X O . . . . . 6 4 5 . . . O X . . | $$ | . . X O . . . . O . X 8 O . O X . . . | $$ | . . . . . . . . . . . . . . O X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

however H5 seems to be a vital point that Katago wants to play at almost every move.

jlt · Post by **jlt** » Mon Jan 03, 2022 10:09 am

P.S. For your last question, I thought about this tesuji but I am not sure it works.

jlt · Post by **jlt** » Mon Jan 17, 2022 4:06 am

Position #61, Balck to play. Again a rather basic shape.

Click Here To Show Diagram Code: [go]$$Bc $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . X O . O X . . O . . . . . . X . . . | $$ | . . X O . X . X O , . O . . X , . . . | $$ | . . X O . . . . X . . . . . . . O . . | $$ | . . X O O . . X . . . . . . . . . . . | $$ | . . . X O . . . . . . . . . . . . . . | $$ | . . . X O . . O . . . . . . . . O . . | $$ | . . . X . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . O . . . | $$ | . . . X . . . . . O . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Knotwilg · Post by **Knotwilg** » Mon Jan 17, 2022 5:17 am

Hane at the head of two, I assume. BTW before counting the stones I assumed from the shape it was White's turn to play and I would also play there.

Click Here To Show Diagram Code: [go]$$Bc $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . X O . O X . 1 O . . . . . . X . . . | $$ | . . X O . X . X O , . O . . X , . . . | $$ | . . X O . . . . X . . . . . . . O . . | $$ | . . X O O . . X . . . . . . . . . . . | $$ | . . . X O . . . . . . . . . . . . . . | $$ | . . . X O . . O . . . . . . . . O . . | $$ | . . . X . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . O . . . | $$ | . . . X . . . . . O . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$Bc Alternative $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . X O . O X . 2 O . . . . . . X . . . | $$ | . . X O . X . X O , . O . . X , . . . | $$ | . . X O . . 4 . X . . . . . . . O . . | $$ | . . X O O . . X . . . . . . . 1 3 . . | $$ | . . . X O . . . . . . . . . . . . . . | $$ | . . . X O . . O . . . . . . . . O . . | $$ | . . . X . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . O . . . | $$ | . . . X . . . . . O . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

jlt · Post by **jlt** » Mon Jan 17, 2022 5:25 am

Correct!

jlt · Post by **jlt** » Sat Feb 12, 2022 1:43 am

Position #62, Black to play. White just played this move:

Click Here To Show Diagram Code: [go]$$Bc Black to play $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . O O O . . | $$ | . . . . . . . . . . . . . O X O X X . | $$ | . . . O . O . . . , . . . . X X . . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . X X . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . W . . . . . . . . . . . . . . | $$ | . . O , X . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O O . . | $$ | . . X X . . . . . . . . . . . O X . . | $$ | . . O , O . . . . , . . . . . , X . . | $$ | . . . O . . . . . . . . . X . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Black has at least two good responses. In the game I played

which is approved by Katago, but I didn't get the continuation right. So how should Black continue after this?

Possible answer:

Katago considers only one move:

Click Here To Show Diagram Code: [go]$$Bc $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . O O O . . | $$ | . . . . . . . . . . . . . O X O X X . | $$ | . . . O . O . . . , . . . . X X . . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . X X . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . d 1 X O . . . . . . . . . . . . . . | $$ | . a O O X . . . . , . . . . . , . . . | $$ | . . . . b . . . . . . . . . . . . . . | $$ | . . X c . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O O . . | $$ | . . X X . . . . . . . . . . . O X . . | $$ | . . O , O . . . . , . . . . . , X . . | $$ | . . . O . . . . . . . . . X . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

This moves threatens the hane "a", so White will have to defend. Before playing "d", White can play at "b" or "c". Let's for instance examine "b".

Click Here To Show Diagram Code: [go]$$Bc $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . O O O . . | $$ | . . . . . . . . . . . . . O X O X X . | $$ | . . . O . O . . . , . . . . X X . . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . X X . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . 5 9 . 8 . . . . . . . . . . . . . . | $$ | . 4 1 X O . . . . . . . . . . . . . . | $$ | . 6 O O X 3 . . . , . . . . . , . . . | $$ | . . . . 2 7 . . . . . . . . . . . . . | $$ | . . X 0 . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O O . . | $$ | . . X X . . . . . . . . . . . O X . . | $$ | . . O , O . . . . , . . . . . , X . . | $$ | . . . O . . . . . . . . . X . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$Bcm11 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . O O O . . | $$ | . . . . . . . . . . . . . O X O X X . | $$ | . . . O . O . . . , . . . . X X . . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . X X . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . X X . O . . . . . . . . . . . . . . | $$ | . O X X O . . . . . . . . . . . . . . | $$ | . O O O X X . . . , . . . . . , . . . | $$ | . . . . O X . . . . . . . . . . . . . | $$ | . . B O . . . . . . . . . . . . . . . | $$ | . . 2 . 1 . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O O . . | $$ | . . X X . . . . . . . . . . . O X . . | $$ | . . O , O . . . . , . . . . . , X . . | $$ | . . . O . . . . . . . . . X . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

The idea being to sacrifice the marked stone, enclose White in sente and get the influence. Black is cut into two pieces but can manage the fight.

jlt · Post by **jlt** » Tue Feb 22, 2022 2:36 pm

Position #63, White to play in the lower left quadrant. At least two good moves are possible.

Click Here To Show Diagram Code: [go]$$Wc White to play $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . X . . . . . | $$ | . . . O . . . . . , . . . . . , X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X , X . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . O . O . O . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . . . . . . . . . . . . O O . . | $$ | . . . , X X X . . , . . . . . , X . . | $$ | . . . O O . O O . . . . . X . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Life In 19x19

Shapes to remember (SDK level)

Re: Shapes to remember (SDK level)

Re: Shapes to remember (SDK level)

Re: Shapes to remember (SDK level)

Re: Shapes to remember (SDK level)

Re: Shapes to remember (SDK level)

Re: Shapes to remember (SDK level)

Re: Shapes to remember (SDK level)

Re: Shapes to remember (SDK level)

Re: Shapes to remember (SDK level)

Re: Shapes to remember (SDK level)

Re: Shapes to remember (SDK level)

Re: Shapes to remember (SDK level)

Re: Shapes to remember (SDK level)

Re: Shapes to remember (SDK level)

Re: Shapes to remember (SDK level)