Life In 19x19

Posted: **Sun Feb 06, 2011 1:28 pm**

All of the posts lately about the endgame have made me realize that my endgame is... slovenly, to say the least. I thought that I would practice concentration and patience by making myself endgame problems drawn from real games.

I have no idea whether this will be helpful or not, nor whether the problems will be too easy, too hard, or just plain boring. (Actually, "boring" isn't a huge con, since I wish to learn to focus.) But if anyone wants to play along, please join in! I'll post the answers (that is, how the game actually went) once I've tried to solve them all.

The problems are "best play for each side," not to win.

Endgame Problem #1

Endgame Problem #2

Endgame Problem #3

Endgame Problem #4

Endgame Problem #5

Endgame Problem #6

Endgame Problem #7

Endgame Problem #8

Endgame Problem #9

Posted: **Sun Feb 06, 2011 3:32 pm**

My first attempt:

Click Here To Show Diagram Code: [go]$$c Position at move 237. Black to play. $$ --------------------------------------- $$ | . . . . . . O . X . X . . . . X e O . | $$ | . . . . X O . O O X . X X . . X O . O | $$ | . O O O O O O X X X X O . d X . X O . | $$ | a O X X O . O O X O O . O O X , X O . | $$ | a X X . X O . . O . . O X X X X O . . | $$ | . . X . X O . . . O O O O O X O O O . | $$ | . . X . X X O O O X O . O X X X O O O | $$ | . . . X . . X . c X O . O O X X X O X | $$ | . . . . . . . X X . X O O X . . X X X | $$ | . . . , . X X X . X X X O X . X . X . | $$ | . . . X X O O O X . X O O O X . X O O | $$ | . . . X O b O X X X O X X X X X O . O | $$ | . . X f X . O X . X O O X X O X O O . | $$ | . . X O X O O O X O . O X O O O . . . | $$ | . X O O X O X X X O O O X X X O . . . | $$ | . X O O . O O . X O . X . X O O . . . | $$ | . . X O . O . O O O . X X X X X O . . | $$ | . . X O X X O . O X X . O O X O O . . | $$ | . . . X . . . O . O . . . X O O . . . | $$ ---------------------------------------[/go]

I think I'll count "e" as black's 1 pt sente (the ko is very, very heavy for W... unless it's 100% W wins kos, I think he needs to respond). "c" is a 1 pt move with a 2pt follow-up for W. "a" is a 1 pt. move which I think has a much bigger follow-up for W (about a 5 pt. sente?), whereas if B plays at "a" the follow-up is 1pt with a ... 1.5 pt follow-up? This is all to get around to "b"; if B plays B, it's a 1pt gote, whereas if W plays it it's a 1 pt gote with a 9 pt followup. Because it has such a big follow-up, I'm pretty sure that any Black move except "a" can be ignored to play "b". The move at "d" looks like a 1 pt with a 3 pt followup.

This is harder than I thought it would be; I was a little worried that the temperature would be extremely low and there would be no interesting choices. So, I think it should go something like this:

Click Here To Show Diagram Code: [go]$$Bc B11 at A14. $$ --------------------------------------- $$ | . . . . . . O . X . X . . . . X 1 O . | $$ | . . . . X O . O O X . X X . . X O 2 O | $$ | 6 O O O O O O X X X X O . 7 X . X O . | $$ | 3 O X X O . O O X O O . O O X , X O . | $$ | 0 X X . X O . . O . . O X X X X O . . | $$ | . . X . X O . . . O O O O O X O O O . | $$ | . . X . X X O O O X O . O X X X O O O | $$ | . . . X . . X . 8 X O . O O X X X O X | $$ | . . . . . . . X X 9 X O O X . . X X X | $$ | . . . , . X X X . X X X O X . X . X . | $$ | . . . X X O O O X . X O O O X . X O O | $$ | . . . X O 4 O X X X O X X X X X O . O | $$ | . . X 5 X . O X . X O O X X O X O O . | $$ | . . X O X O O O X O . O X O O O . . . | $$ | . X O O X O X X X O O O X X X O . . . | $$ | . X O O . O O . X O . X . X O O . . . | $$ | . . X O . O . O O O . X X X X X O . . | $$ | . . X O X X O . O X X . O O X O O . . | $$ | . . . X . . . O . O . . . X O O . . . | $$ ---------------------------------------[/go]

That took me around 20 minutes, and I still need to count to see who wins. I think I'll check the correct sequence after I've done more of the problems.

Posted: **Sun Feb 06, 2011 3:35 pm**

Whose games are these?

Posted: **Sun Feb 06, 2011 4:40 pm**

#1

Click Here To Show Diagram Code: [go]$$c Position at move 237. Black to play. $$ --------------------------------------- $$ | . . . . . . O . X . X . . . . X e O . | $$ | . . . . X O . O O X . X X . . X O . O | $$ | . O O O O O O X X X X O . d X . X O . | $$ | a O X X O . O O X O O . O O X , X O . | $$ | a X X . X O . . O . . O X X X X O . . | $$ | . . X . X O . . . O O O O O X O O O . | $$ | . . X . X X O O O X O . O X X X O O O | $$ | . . . X . . X . c X O . O O X X X O X | $$ | . . . . . . . X X . X O O X . . X X X | $$ | . . . , . X X X . X X X O X . X . X . | $$ | . . . X X O O O X . X O O O X . X O O | $$ | . . . X O b O X X X O X X X X X O . O | $$ | . . X f X . O X . X O O X X O X O O . | $$ | . . X O X O O O X O . O X O O O . . . | $$ | . X O O X O X X X O O O X X X O . . . | $$ | . X O O . O O . X O . X . X O O . . . | $$ | . . X O . O . O O O . X X X X X O . . | $$ | . . X O X X O . O X X . O O X O O . . | $$ | . . . X . . . O . O . . . X O O . . . | $$ ---------------------------------------[/go]

I read "a" as 2 points gote. "b" as 1 point reverse sente. "c" as 2.5 points gote. "d" as 1 point reverse sente, "e" as complicated. If White ignores, the capture is dangerous. White must play T15, allowing Black to play T19. So that's 5 points if Black gets to connect, and at least 3 points, but in gote. I'll throw 4 into the wind as my guess, and play as follows:

Click Here To Show Diagram Code: [go]$$c Position at move 237. Black to play. $$ --------------------------------------- $$ | . . . . . . O . X . X . . . . X 5 O . | $$ | . . . . X O . O O X . X X . . X O 6 O | $$ | 8 O O O O O O X X X X O . 1 X . X O . | $$ | 7 O X X O . O O X O O . O O X , X O . | $$ | 9 X X . X O . . O . . O X X X X O . . | $$ | . . X . X O . . . O O O O O X O O O . | $$ | . . X . X X O O O X O . O X X X O O O | $$ | . . . X . . X . 4 X O . O O X X X O X | $$ | . . . . . . . X X 0 X O O X . . X X X | $$ | . . . , . X X X . X X X O X . X . X . | $$ | . . . X X O O O X . X O O O X . X O O | $$ | . . . X O 2 O X X X O X X X X X O . O | $$ | . . X 3 X . O X . X O O X X O X O O . | $$ | . . X O X O O O X O . O X O O O . . . | $$ | . X O O X O X X X O O O X X X O . . . | $$ | . X O O . O O . X O . X . X O O . . . | $$ | . . X O . O . O O O . X X X X X O . . | $$ | . . X O X X O . O X X . O O X O O . . | $$ | . . . X . . . O . O . . . X O O . . . | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$c Position at move 237. Black to play. $$ --------------------------------------- $$ | . . . . . . O W X B X . . . . X X O . | $$ | . . . . X O . O O X . X X . . X O O O | $$ | O O O O O O O X X X X O B X X . X O . | $$ | X O X X O . O O X O O W O O X , X O . | $$ | X X X . X O . . O . . O X X X X O . . | $$ | . . X . X O . . . O O O O O X O O O . | $$ | . . X . X X O O O 2 O . O X X X O O O | $$ | . . . X . . X B O 1 O . O O X X X O X | $$ | . . . . . . . X X 3 X O O X . . X X X | $$ | . . . , . X X X . X X X O X . X . X W | $$ | . . . X X O O O X . X O O O X . X O O | $$ | . . . X O O O X X X O X X X X X O . O | $$ | . . X X X W O X B X O O X X O X O O . | $$ | . . X O X O O O X O . O X O O O . . . | $$ | . X O O X O X X X O O O X X X O . . . | $$ | . X O O B O O W X O B X . X O O . . . | $$ | . . X O W O . O O O W X X X X X O . . | $$ | . . X O X X O . O X X B O O X O O . . | $$ | . . B X B W W O W O B B W W O O . . . | $$ ---------------------------------------[/go]

Black wins by 0.5 in mine, loses by 0.5 in yours. However, I don't claim perfect play by any means, and I spent about 90 seconds on the board. :b1:

at

seems the same too.

Posted: **Sun Feb 06, 2011 4:45 pm**

#2

Posted: **Sun Feb 06, 2011 4:55 pm**

#3

#4

Click Here To Show Diagram Code: [go]$$ Position at move 233. Black to play. $$ --------------------------------------- $$ | . X . . . . . . . . X O O . . O . . . | $$ | O O X X . . . . . . . X O . O X O O . | $$ | . X O X X . . . . . X X X O . X O . O | $$ | . O O O X O . . . , . X O O O X X O O | $$ | . . O X X . . . X X . X X O X O X X X | $$ | . O . O X . . . X O O X X O X O . X . | $$ | O O O O X . . . O . O X O O X X . . . | $$ | X O X X . . . . . . X O O . X . a X . | $$ | d X . X . . . . . . X X O O X O O O X | $$ | X X X X . . X X X X X O . . O O X X . | $$ | X O X O X X O O X O O O O O O O O X . | $$ | O O X O O O . O X X . . X O . O O X . | $$ | O . O . . . O O O X X X X O O X X . . | $$ | O . O . . . . O X X O X O X X X X X X | $$ | . O . . X X O c O X O O O . . O O O X | $$ | . . O , X O O O X X X . . O O O . O O | $$ | . . . O O O . . O O . X X b X O O X . | $$ | . . . . . . O O X X X . . X X X O . . | $$ | . . . . . . . O O X . . . . X O O . . | $$ ---------------------------------------[/go]

"a" is sente for White, else it's a truly horribly heavy Black ko. "b" is also very sente. On the offchance that White is ko monster, we can play "b" first, and leave "c" and "d" as mutual kos (you're gonna get one each)

Click Here To Show Diagram Code: [go]$$ Position at move 233. Black to play. $$ --------------------------------------- $$ | . X . . . . . . . . X O O . . O . . . | $$ | O O X X . . . . . . . X O . O X O O . | $$ | . X O X X . . . . . X X X O . X O . O | $$ | . O O O X O . . . , . X O O O X X O O | $$ | . . O X X . . . X X . X X O X O X X X | $$ | . O . O X . . . X O O X X O X O . X . | $$ | O O O O X . . . O . O X O O X X 3 . . | $$ | X O X X . . . . . . X O O . X . 2 X . | $$ | 5 X . X . . . . . . X X O O X O O O X | $$ | X X X X . . X X X X X O . . O O X X . | $$ | X O X O X X O O X O O O O O O O O X . | $$ | O O X O O O . O X X . . X O . O O X . | $$ | O . O . . . O O O X X X X O O X X . . | $$ | O . O . . . . O X X O X O X X X X X X | $$ | . O . . X X O 4 O X O O O . . O O O X | $$ | . . O , X O O O X X X . . O O O . O O | $$ | . . . O O O . . O O . X X 1 X O O X . | $$ | . . . . . . O O X X X . . X X X O . . | $$ | . . . . . . . O O X . . . . X O O . . | $$ ---------------------------------------[/go]

Can't see any other points.

#5

#6

A single half point ko:

Click Here To Show Diagram Code: [go]$$ Position at move 313. Black to play. $$ --------------------------------------- $$ | . . . . . . . . . . . . X X O O . O O | $$ | . . . X X . . . . X X X X O O . O O 1 | $$ | . X X X X X X X . . O O O X X O O X 4 | $$ | X X X O X O O O X X X . 8 X O O X X X | $$ | O X O O X O . O O O X X X 9 X X O X . | $$ | O O O O O O O . X X X O O X X O O 2 3 | $$ | . O X X X X O O O . X X O O X X X X X | $$ | O O X . X O O X X X X O O O X . O O X | $$ | X O O X . X X . X X X X O O O O O . O | $$ | X X X , X X . X O O X O X . . X X O . | $$ | . O X X . X X O O O O O O . . O O . O | $$ | O O O X X X . X O X O O . O . O X O O | $$ | . O . O O X X . X X X O . O . O X X . | $$ | . . O O O O O X X . X X O . . O O O O | $$ | . O O X X X O O X X O O . . O X O X X | $$ | . O X O O X X X X X X O O O O X X . X | $$ | O X X . O X O O X . O O X X O X X X . | $$ | 5 X . X O O . O X X . O X . X X . . X | $$ | . 6 O X O . O O X . . O X X . X X . . | $$ ---------------------------------------[/go]

at

at

Click Here To Show Diagram Code: [go]$$ Position at move 313. Black to play. $$ --------------------------------------- $$ | . . . . . . . . . . . . X X O O . O O | $$ | . . . X X . . . . X X X X O O . O O 3 | $$ | . X X X X X X X . . O O O X X O O X W | $$ | X X X O X O O O X X X . O X O O X X X | $$ | O X O O X O . O O O X X X X X X C X . | $$ | O O O O O O O . X X X O O X X C C C X | $$ | . O X X X X O O O . X X O O X X X X X | $$ | O O X . X O O X X X X O O O X . O O X | $$ | X O O X . X X . X X X X O O O O O . O | $$ | X X X , X X . X O O X O X . . X X O . | $$ | . O X X . X X O O O O O O . . O O . O | $$ | O O O X X X . X O X O O . O . O X O O | $$ | . O . O O X X . X X X O . O . O X X . | $$ | . . O O O O O X X . X X O . . O O O O | $$ | . O O X X X O O X X O O . . O X O X X | $$ | . O X O O X X X X X X O O O O X X . X | $$ | O X X . O X O O X . O O X X O X X X . | $$ | X X . X O O . O X X 1 O X . X X . . X | $$ | . O O X O . O O X . 2 O X X . X X . . | $$ ---------------------------------------[/go]

Can't see any more ko threats. :b5:

connects and pass

Posted: **Sun Feb 06, 2011 5:05 pm**

snorri wrote:Whose games are these?

They're recent pro games.

Posted: **Sun Feb 06, 2011 5:35 pm**

#7

#8

Click Here To Show Diagram Code: [go]$$ Position at move 268. White to play. $$ --------------------------------------- $$ | . . . . . . . . . e . O . O d . . . . | $$ | . . . . X O O . O X O O O X X . . . . | $$ | . . . O O X O O O O X X X X . X . X X | $$ | . . . O X X X X O X X X O O X , X X O | $$ | . . O O O O X . X X X O . . O X X O c | $$ | . . O O X X X X X O . O . . O O . O O | $$ | . O X O O O O X O O O O O O X O O O . | $$ | . O X X X O . O X . O . O X X X X O X | $$ | . O X X O O . O X X O O X X X . X X X | $$ | . O X X X X O O X O X X X O O O X . X | $$ | . O X O . X O X X O O O X X O X X X O | $$ | O O O O X . X X X O . O O X X . O O O | $$ | O X b O a f O X . X X O O O X X O . . | $$ | X . X O . O O X . X . X O . O O O . . | $$ | . . X g O X X . X . X X . O . O O O O | $$ | . . . X X . . X O X . X O O X X O X X | $$ | . . . X . O X X O O X X O X X . X X . | $$ | . . . . . X X O O . O O O O X X . . . | $$ | . . . . . X O O . . . . . O O X . . . | $$ ---------------------------------------[/go]

"a" is an interesting point. That ko is frightening for Black, and White stands to lose very little, so depending on Black's threat level, I expect Black has to connect, allowing White to play "e" for another ko. Why is this useful? Because there are two half point kos at "c" and the "d" area. "b" is a point in sente. So I suspect White will take this point, then "a", then "f". Black plays "g" to prevent White getting the point as White cannot yet play "d". White captures at "e", Black takes "d", White connects a ko, Black takes a ko, and then they connect one each.

Click Here To Show Diagram Code: [go]$$Wc Position at move 268. White to play. $$ --------------------------------------- $$ | . . . . . . . . . 7 . O 0 O 6 . . . . | $$ | . . . . X O O . O X O O O X X . . . . | $$ | . . . O O X O O O O X X X X . X . X X | $$ | . . . O X X X X O X X X O O X , X X O | $$ | . . O O O O X . X X X O . . O X X O . | $$ | . . O O X X X X X O . O . . O O . O O | $$ | . O X O O O O X O O O O O O X O O O . | $$ | . O X X X O . O X . O . O X X X X O X | $$ | . O X X O O . O X X O O X X X . X X X | $$ | . O X X X X O O X O X X X O O O X . X | $$ | . O X O . X O X X O O O X X O X X X O | $$ | O O O O X 4 X X X O . O O X X . O O O | $$ | O X 1 O 3 5 O X . X X O O O X X O . . | $$ | X 2 X O 9 O O X . X . X O . O O O . . | $$ | . . X 8 O X X . X . X X . O . O O O O | $$ | . . . X X . . X O X . X O O X X O X X | $$ | . . . X . O X X O O X X O X X . X X . | $$ | . . . . . X X O O . O O O O X X . . . | $$ | . . . . . X O O . . . . . O O X . . . | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$Wc Position at move 268. White to play. $$ --------------------------------------- $$ | . . . . . . . . . O . O X 2 X . . . . | $$ | . . . . X O O . O C O O O X X . . . . | $$ | . . . O O X O O O O X X X X . X . X X | $$ | . . . O X X X X O X X X O O X , X X O | $$ | . . O O O O X . X X X O . . O X X O 1 | $$ | . . O O X X X X X O . O . . O O . O O | $$ | . O X O O O O X O O O O O O X O O O . | $$ | . O X X X O . O X . O . O X X X X O X | $$ | . O X X O O . O X X O O X X X . X X X | $$ | . O X X X X O O X O X X X O O O X . X | $$ | . O X O . X O X X O O O X X O X X X O | $$ | O O O O X X X X X O . O O X X . O O O | $$ | O X O O O O O X . X X O O O X X O . . | $$ | X X X O O O O X . X . X O . O O O . . | $$ | . . X X O X X . X . X X . O . O O O O | $$ | . . . X X . . X O X . X O O X X O X X | $$ | . . . X . O X X O O X X O X X . X X . | $$ | . . . . . X X O O . O O O O X X . . . | $$ | . . . . . X O O . . . . . O O X . . . | $$ ---------------------------------------[/go]

#9

Click Here To Show Diagram Code: [go]$$ Position at move 240. White to play. $$ --------------------------------------- $$ | . . . . . . X X O . b . . . . . . d . | $$ | . . X . X X X O . O X X . . . . X X O | $$ | . X O O X O O O O O O X X X X . X O . | $$ | X X . X O . O . . O . O . O O X X O . | $$ | O O X X . O X X . O O O O . . X O f . | $$ | O . O . X X X O O O X X X O . X O . . | $$ | . O O . X O X O . . O . X X X X O . . | $$ | O X X X X O O . . . . O . . O X X O . | $$ | . O O X . X O . . O . . O O O O O . . | $$ | O . . O X X O . X O X O O X O , O . . | $$ | O O O O . X X O O X O O X X X O O . . | $$ | O X O X X X O O . X X X X . X X O O . | $$ | X a X . X O O . X X X . . . . X X O . | $$ | c X X X e X O X X O O X . . . X O O O | $$ | X X O X X O O O O O X . . . . . X X O | $$ | X O O O O . . . O X X X . . . , X . X | $$ | O O . . . O . . O O O X . O X . . X . | $$ | . . . . . . O O . O X . X X . . . . . | $$ | . . . . . . O X X X . X . . . . . . . | $$ ---------------------------------------[/go]

"a" is always bigger than a half point ko - In this case, it's kinda huge, because White getting "a" and "e" gives Black a liberty problem. So, I predict after "a", Black will take the remaining point at the top with "b", White will capture at "c", forcing Black to connect at "e", White connects at "a", Black ataris at the top, White connects, and Black plays out the shortage of liberties at "d". White cannot play there first because of the threat of Black "f", creating a ko that White cannot really win:

Click Here To Show Diagram Code: [go]$$Wc Position at move 240. White to play. $$ --------------------------------------- $$ | . . . . . . X X O 6 2 . . . . . . 8 0 | $$ | . . X . X X X O 7 O X X . . . . X X O | $$ | . X O O X O O O O O O X X X X . X O 9 | $$ | X X . X O . O . . O . O . O O X X O . | $$ | O O X X . O X X . O O O O . . X O W . | $$ | O . O . X X X O O O X X X O . X O . . | $$ | . O O . X O X O . . O . X X X X O . . | $$ | O X X X X O O . . . . O . . O X X O . | $$ | . O O X . X O . . O . . O O O O O . . | $$ | O . . O X X O . X O X O O X O , O . . | $$ | O O O O . X X O O X O O X X X O O . . | $$ | O . O X X X O O . X X X X . X X O O . | $$ | 5 1 X . X O O . X X X . . . . X X O . | $$ | 3 X X X 4 X O X X O O X . . . X O O O | $$ | X X O X X O O O O O X . . . . . X X O | $$ | X O O O O . . . O X X X . . . , X . X | $$ | O O . . . O . . O O O X . O X . . X . | $$ | . . . . . . O O . O X . X X . . . . . | $$ | . . . . . . O X X X . X . . . . . . . | $$ ---------------------------------------[/go]

Posted: **Sun Feb 06, 2011 5:39 pm**

My (almost certainly failed) attempt at #2

Click Here To Show Diagram Code: [go]$$Bc Position at move 299. Black to play. $$ --------------------------------------- $$ | . X . X . X X X X . . O O . b . a . . | $$ | O X X . X X O O X O O X O O X . O X . | $$ | . O O X . X . O O . O X X X X X O X X | $$ | . O X O X X X X X O . O O O X X X X X | $$ | . O . O . . . O O O O O . O X X X O X | $$ | . . . O O . X X O X O O O X . X O O O | $$ | . . X O X X X . X X X O O X X O O O . | $$ | . . O X . . X . X X O X X X X O X O . | $$ | . . O X . . X . . X O O O X . O X X O | $$ | . . O O X X . . X O . O X X X O X X O | $$ | O O . O X . X X X O O O O O O O O X . | $$ | X O X O . X . . X X X X O O . O X . X | $$ | X X O O O O X . X O X O . . O . X X O | $$ | . . X X . X X X O O O O O O X X X O O | $$ | X X X X . X O X X . O X X X O X O O O | $$ | O X O X O O O X . O O O X . . X X O . | $$ | O O O O . O X X O O X X . X . X O O X | $$ | . . . . . O O X O X . . . . X O O . O | $$ | . . . . . O X X X . . . . . . X . O . | $$ ---------------------------------------[/go]

This problem is confusing because it doesn't look like there are ten moves left (all of these diagrams are about a dozen moves before the end of the game). I looked to see if W could get a seki with a play around "a" (no), and then there's yose at "b", and that's it.

If it were W to move I would assume that W plays "b," and then there's a short ko over the last point. But since it's B to move this game must be area scoring.

(So far assuring myself that there are no plays under Japanese rules has taken about 10 minutes.)

No, the more I think about it... there are too many dame and ko threats for this to be close to the end of a ko fight or dame-filling. I'm befuddled. Maybe I messed up the diagram. I'll check this when I finish the others. Anyway, my solution:

Click Here To Show Diagram Code: [go]$$Bc Position at move 299. Black to play. $$ --------------------------------------- $$ | . X . X . X X X X . . O O . 1 . . . . | $$ | O X X . X X O O X O O X O O X . O X . | $$ | . O O X . X . O O . O X X X X X O X X | $$ | . O X O X X X X X O . O O O X X X X X | $$ | . O . O . . . O O O O O . O X X X O X | $$ | . . . O O . X X O X O O O X . X O O O | $$ | . . X O X X X . X X X O O X X O O O . | $$ | . . O X . . X . X X O X X X X O X O . | $$ | . . O X . . X . . X O O O X . O X X O | $$ | . . O O X X . . X O . O X X X O X X O | $$ | O O . O X . X X X O O O O O O O O X . | $$ | X O X O . X . . X X X X O O . O X . X | $$ | X X O O O O X . X O X O . . O . X X O | $$ | . . X X . X X X O O O O O O X X X O O | $$ | X X X X . X O X X . O X X X O X O O O | $$ | O X O X O O O X . O O O X . . X X O . | $$ | O O O O . O X X O O X X . X . X O O X | $$ | . . . . . O O X O X . . . . X O O . O | $$ | . . . . . O X X X . . . . . . X . O . | $$ ---------------------------------------[/go]

Posted: **Sun Feb 06, 2011 5:43 pm**

Wow, topazg has powered through these problems already. I'm going to post the solutions for him, although I probably won't look at any of them until I finish. Just as a warning, all nine solutions are under the hide tag.

Click Here To Show Diagram Code: [go]$$B Moves 237 to 246 $$ --------------------------------------- $$ | . . . . . . O . X . X . . . . 1 9 O . | $$ | . . . . X O . O O X . X X 5 . X O 0 O | $$ | . O O O O O O X X X X O . 4 X . X O . | $$ | 8 O X X O . O O X O O . O O X , X O . | $$ | 6 X X . X O . . O . . O X X X X O . . | $$ | 7 . X . X O . . . O O O O O X O O O . | $$ | . . X . X X O O O X O . O X X X O O O | $$ | . . . X . . X . . X O . O O X X X O X | $$ | . . . . . . . X X . X O O X . . X X X | $$ | . . . , . X X X . X X X O X . X . X . | $$ | . . . X X O O O X . X O O O X . X O O | $$ | . . . X O 2 O X X X O X X X X X O . O | $$ | . . X 3 X . O X . X O O X X O X O O . | $$ | . . X O X O O O X O . O X O O O . . . | $$ | . X O O X O X X X O O O X X X O . . . | $$ | . X O O . O O . X O . X . X O O . . . | $$ | . . X O . O . O O O . X X X X X O . . | $$ | . . X O X X O . O X X . O O X O O . . | $$ | . . . X . . . O . O . . . X O O . . . | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$B Moves 299 to 308 $$ --------------------------------------- $$ | . X . X . X X X X . 2 O O 4 3 . 5 . . | $$ | O X X . X X O O X O O X O O X . O X . | $$ | 0 O O X . X . O O 8 O X X X X X O X X | $$ | . O X O X X X X X O . O O O X X X X 1 | $$ | . O . O . . . O O O O O . O X X X O X | $$ | . . . O O . X X O X O O O X . X O O O | $$ | . . X O X X X . X X X O O X X O O O . | $$ | . . O X . . X . X X O X X X X O X O 6 | $$ | . . O X . . X . . X O O O X . O X X O | $$ | . . O O X X . . X O . O X X X O X X O | $$ | O O . O X . X X X O O O O O O O O X . | $$ | X O X O . X . . X X X X O O . O X 9 X | $$ | X X O O O O X . X O X O . . O . X X O | $$ | . . X X . X X X O O O O O O X X X O O | $$ | X X X X . X O X X . O X X X O X O O O | $$ | O X O X O O O X . O O O X . . X X O . | $$ | O O O O . O X X O O X X . X . X O O X | $$ | . . . . . O O X O X . . . . X O O . O | $$ | . . . . . O X X X . . . . . 7 X . O . | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$W Moves 322 to 331 $$ --------------------------------------- $$ | 8 X 2 X X . X . X . X . . . . . . . . | $$ | O O X X . X . X . X . X X . . . . . . | $$ | . O O O X X X . . X . X O X X . . X X | $$ | . . O X O 5 X X . X X O O O X , X X O | $$ | . 1 X X O O O X X O . O X X X . X O O | $$ | O O O O 3 6 X O O O O O O O O X X O . | $$ | X X X 4 X X X X O O . O X X X X O O X | $$ | X . X X . X X . X X O O 9 X X O O O . | $$ | O X X O X . . X X O O O X X X X O . . | $$ | O O O O O X X X X X X O O X O X O . . | $$ | X O O O O X . X O X O O O O O O O . . | $$ | . O X X X X X O O X X O . X O X . . . | $$ | . O X O X O O . O X X O O O X O O . . | $$ | O . O O O O . O O X O X X X X X O . . | $$ | X O O X X X X . O O O O X X O O O O . | $$ | . O O O X O O O O O . O O X X X O . . | $$ | O . O X . X O X X X O O X X . X X O O | $$ | O O X X . X X . X X O O X X O X . X O | $$ | 7 X X X . X . X X X X O O X . . . X 0 | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$B Moves 233 to 242 $$ --------------------------------------- $$ | . X . . . . . . . . X O O . . O . . . | $$ | O O X X . . . . . . . X O . O X O O . | $$ | . X O X X . . . . . X X X O . X O . O | $$ | . O O O X O . . . , . X O O O X X O O | $$ | . . O X X . . . X X . X X O X O X X X | $$ | . O . O X . . . X O O X X O X O . X . | $$ | O O O O X . . . O . O X O O X X 3 . . | $$ | X O X X . . . . . . X O O . X . 2 X . | $$ | 9 X . X . . . . . . X X O O X O O O X | $$ | X X X X . . X X X X X O . . O O X X . | $$ | X O X O X X O O X O O O O O O O O X . | $$ | O O X O O O . O X X . . X O . O O X . | $$ | O . O . . . O O O X X X X O O X X . . | $$ | O . O . . . . O X X O X O X X X X X X | $$ | . O . . X X O 0 O X O O O 8 . O O O X | $$ | . . O , X O O O X 1 X . . O O O . O O | $$ | . . . O O O . 4 O O 5 X X 6 X O O X . | $$ | . . . . . . O O X X X . 7 X X X O . . | $$ | . . . . . . . O O X . . . . X O O . . | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$B Moves 295 to 304 $$ --------------------------------------- $$ | 9 O X 0 X O . O . O O X . . . . . . . | $$ | O 7 X 8 X O . O O O X . X . . . . . . | $$ | X X X X O O O O O X X X O . . . X X X | $$ | O O X O O O O X O O X X X X X , X O O | $$ | 6 O O O 5 O X X X X O X O O X . . X O | $$ | X X X X X X . X . X O O O O O X X X O | $$ | X O X X X . X . X O X X O O O O O X O | $$ | X O O X O X X X O O . O X X O O . O O | $$ | X O O O O O X O O . O O O X X O O . . | $$ | X X X X X O O O . X O O X X X X O . . | $$ | X O O O O X X O O O X O O 1 X O O . . | $$ | X O O X X X O O X O X X O O X O X . . | $$ | O O X X O X X X X X . X X X X X O . . | $$ | . O O O O O X X X X X X 2 3 4 X O . . | $$ | O X . O O O X O O O O O O O O O . . . | $$ | . . O O X O X X O O O O X O X O O . . | $$ | O O O X X X X . X X O X X X X X O . . | $$ | X X O X . . . X . X X O . . . X X O . | $$ | . X X . . . . . . . . . . . . X O O . | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$B Moves 313 to 322 $$ --------------------------------------- $$ | . . . . . . . . . . . . X X O O . O O | $$ | . . . X X . . . . X X X X O O . O O 2 | $$ | . X X X X X X X . . O O O X X O O X O | $$ | X X X O X O O O X X X . . X O O X X X | $$ | O X O O X O . O O O X X X . X X O X . | $$ | O O O O O O O 6 X X X O O X X O O . . | $$ | . O X X X X O O O 5 X X O O X X X X X | $$ | O O X . X O O X X X X O O O X 0 O O X | $$ | X O O X . X X . X X X X O O O O O . O | $$ | X X X , X X . X O O X O X . . X X O . | $$ | 8 O X X . X X O O O O O O . . O O . O | $$ | O O O X X X . X O X O O . O . O X O O | $$ | . O . O O X X . X X X O . O . O X X . | $$ | . . O O O O O X X . X X O . . O O O O | $$ | . O O X X X O O X X O O . . O X O X X | $$ | . O X O O X X X X X X O O O O X X . X | $$ | O X X . O X O O X 7 O O X X O X X X . | $$ | . X . X O O . O X 1 3 O X . X X . . X | $$ | . . O X O . O O X 9 4 O X X . X X . . | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$B Moves 243 to 252 $$ --------------------------------------- $$ | . O X X X 9 O O O X . . X X O O . . . | $$ | . O O O X X X X O X . X X O O . . . . | $$ | . . . O X X O X O O X . . X X O O . . | $$ | . . O O 3 X O O . O X X X X X X O O O | $$ | . . O X X X X O O O X O O O O 4 O O X | $$ | . . O X 5 7 8 O X X X O O O O O O X X | $$ | . O X X O O O O O O O O X X X O X X . | $$ | . O X . X X O X O . . O O X . X X . . | $$ | . O X X . . X X X O O X X X . . . . . | $$ | . . O X . . . . . X X X X . . , . . . | $$ | . . O O X . . . . X O O O X X . X . . | $$ | . O X X X X . . . X X X O X O X . X X | $$ | . . O 1 O X . . . X O X O O O X X O X | $$ | . . O 2 O X . . X O O X X O . O O O O | $$ | . . O X X X X X O O 6 X O O O . O O O | $$ | . . O O X 0 O X X O O X X O O O X X X | $$ | . . O X X X O O O O X X . X X X O X . | $$ | . O O X O O O . O . O X . . . . . . . | $$ | . O X X X O . . . . O X . . . . . . . | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$W Moves 268 to 277 $$ --------------------------------------- $$ | . . . . . . . . . 3 . O 5 O 4 . . . . | $$ | . . . . X O O . O X O O O X X . . . . | $$ | . . . O O X O O O O X X X X . X . X X | $$ | . . . O X X X X O X X X O O X , X X 0 | $$ | . . O 1 O O X . X X X O . . O X X O 6 | $$ | . . O O X X X X X O . O . . O O . O O | $$ | . O X O O O O X O O O O O O X O O O . | $$ | . O X X X O . O X . O . O X X X X O X | $$ | . O X X O O . O X X O O X X X . X X X | $$ | . O X X X X O O X O X X X O O O X . X | $$ | . O X O . X O X X O O O X X O X X X O | $$ | O O O O X . X X X O . O O X X . O O O | $$ | O X . O . 8 O X . X X O O O X X O . . | $$ | X . X O 9 O O X . X . X O . O O O . . | $$ | . . X 7 O X X . X . X X 2 O . O O O O | $$ | . . . X X . . X O X . X O O X X O X X | $$ | . . . X . O X X O O X X O X X . X X . | $$ | . . . . . X X O O . O O O O X X . . . | $$ | . . . . . X O O . . . . . O O X . . . | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$W Moves 240 to 249 $$ --------------------------------------- $$ | . . . . . . X X O 3 2 . . . . . . 6 . | $$ | . . X . X X X O . O X X . . . . X X O | $$ | . X O O X O O O O O O X X X X . X O 5 | $$ | X X . X O 9 O . . O . O . O O X X O . | $$ | O O X X 8 O X X . O O O O . . X O . . | $$ | O . O . X X X O O O X X X O . X O 7 . | $$ | . O O . X O X O . . O . X X X X O . . | $$ | O X X X X O O . . . . O . . O X X O . | $$ | . O O X . X O . . O . . O O O O O . . | $$ | O . . O X X O . X O X O O X O , O . . | $$ | O O O O . X X O O X O O X X X O O . . | $$ | O X O X X X O 1 . X X X X . X X O O . | $$ | X 4 X . X O O . X X X . . . . X X O . | $$ | . X X X 0 X O X X O O X . . . X O O O | $$ | X X O X X O O O O O X . . . . . X X O | $$ | X O O O O . . . O X X X . . . , X . X | $$ | O O . . . O . . O O O X . O X . . X . | $$ | . . . . . . O O . O X . X X . . . . . | $$ | . . . . . . O X X X . X . . . . . . . | $$ ---------------------------------------[/go]

Posted: **Sun Feb 06, 2011 5:43 pm**

Ah. These are area scoring? This makes quite a difference ...

Posted: **Sun Feb 06, 2011 5:50 pm**

Hmmm, I missed :b2:

in #8, and I missed :w1:

in #9, so definite fails for me. Also, I notice some discrepancies in #8 comparing the "problem" to the solution ( :w1:

was already on the board when you said White to play), and in #7 Black's atari was already there, so I assumed completing the capture was :b1:

Still, many thanks for posting !

Posted: **Sun Feb 06, 2011 5:56 pm**

topazg wrote:Ah. These are area scoring? This makes quite a difference ...

I was actually under the impression that they were almost all territory scoring, since most of the names were Korean and Japanese. But (stupidly) I didn't keep the data about ruleset, prisoners, or final score, which were stripped out by the .sgf converter. I'll add it back in when I finish the problems.

Posted: **Sun Feb 06, 2011 6:06 pm**

topazg wrote:Hmmm, I missed in #8, and I missed in #9, so definite fails for me. Also, I notice some discrepancies in #8 comparing the "problem" to the solution ( was already on the board when you said White to play), and in #7 Black's atari was already there, so I assumed completing the capture was

Still, many thanks for posting !

Oh gosh, I screwed it up. Sorry about that. Sigh. I guess I'll have to fix the problem diagrams and then wait a week to forget the solutions.

Anyway, glad you enjoyed them.

Life In 19x19

More endgame shenanigans

More endgame shenanigans

Re: More endgame shenanigans

Re: More endgame shenanigans

Re: More endgame shenanigans

Re: More endgame shenanigans

Re: More endgame shenanigans

Re: More endgame shenanigans

Re: More endgame shenanigans

Re: More endgame shenanigans

Re: More endgame shenanigans

Re: More endgame shenanigans

Re: More endgame shenanigans

Re: More endgame shenanigans

Re: More endgame shenanigans