Here are the weekly Go problems for week 48.
Black plays first in all problems and all solutions are labeled ‘correct’. Have fun!
Easy Go problem
Normally white A is a good shape, but here B is better. Black has a clever technique to capture two stones now.
Intermediate Go problem
One of the basic principles of capturing races is to avoid filling shared liberties until the very end.
Hard Go problem
Intuition is important, but in unusual situations reading is unavoidable.
Still want more Go problems?
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Discuss other possible moves
If you have any questions or want to discuss any of these problems, please leave a comment below at any time. You can use the coordinates on the problem images to discuss a move or sequence of moves.
You can also download the solutions as a PDF or SGF file by clicking the links below each problem.
About David Ormerod
In easy problem, you say W better to play B instead of A, but correct shape here, I believe, is G6. After that G5 and F7 are miai for good shape. If W plays F6, as you suggested, after B F7 G6 W’s shape is worse, B’s liberty at G5 remains, and W can’t press with moves like H4 (which in some circumstances may be killing move for lower B group or at least part of it).
I’ve seen intermediate problem in Sakata Eio’s book “Tesuji and anti-suji” and was impressed at the time.
Hard one feels weird; unusual shape.
Hi Flandre,
With the position leading up to the easy problem, choosing between white F6 and G6 can be quite difficult. It depends on what other stones are nearby, but G6 can sometimes be a terrible blunder, whereas F6 (while being bad shape) is rarely that bad. Because, like many things in Go, the answer is ‘it depends’, I wanted to avoid confusing people by saying ‘move x is always best’ and just show a reasonable alternative to the attachment.
If white plays G6, she has to keep in mind that black can choose to squeeze with F6, F5, G5, F7, F4, F5 and then black can extend to E8. In this case, it’s not that bad because white’s already alive in the corner, but it’s important to know that playing G6 gives black the potential to cover the weakness at F3.
If white thinks that black’s going to play the squeeze, then she might decide to simply play F6. It’s bad shape, but it also avoids helping black to make shape. After F6, if black pushes from behind with F7, white will be grateful to just extend. Yes, white is being forced, but black will have to do something about the cut at D7 eventually and then white can play first on the lower side. The further black pushes white into the center, the more severely white can play later.
Thanks for bringing this up. You gave me some good ideas for some other problems
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Reasonable. Though main trouble with G6 is may be that suggesting it in commentary immediately hints how to solve actual problem, making it even easier -_-
Oh, and example of “good empty triangle” is also very nice for kyu players who sometimes too much believe in “good shape” and refuse to play what position requires them to.
Good point, one of the only criticisms I have of the Lee Changho Life and Death books is that quite a few problems say things like “black should have played at A,” and immediately draw your attention to the vital point. Even if you can’t read the text, there’s still a mark on the board. Apart from that they’re excellent.
I’m sort of a fan of bad shape tesuji, because they’re interesting exceptions to the rule and they’re often powerful moves that are overlooked. I’ll try to come up with some problems like that.
Hello David, The hard one is hard to me… I will keep on trying it!. I very like the intermediate, black 3 at A5 is a surprising move .
Hi Jangalf,
The hard one is really strange
. The space isn’t that big, so if you keep trying you’ll get it eventually. In my opinion, regularly solving problems like the intermediate one is more useful because that sort of situation can potentially occur fairly often and knowing black’s first two moves speeds up your reading a lot. The hard one is just a test of your reading, so I don’t include those sorts of problems too often.
Great intermediate problem, but there is no way I can read this in an actual game.
The hard problem is more “natural” it can be done without “reading” all posibilities.
Thanks a lot!
Right Damián, I remember having trouble with something similar to the intermediate problem the first time I saw this sort of idea too. But now that you’ve seen that this is possible, you’re much more likely to see it if this ever happens in your games. To some extent that means you don’t need to read, because now you ‘know’
.
The hard one is quite hard for me that I only got almost correct with a ko (打劫)!
Hey! I did it! But there’s still a ko!
Yes, but you saved a ko threat
. Good job.
Hi. I solved the easy and the hard problems but I’m having trouble on the intermediate problem. Couldn’t you play this sequence of moves(in the intermediate problem): B4-B5-B3-C6-A6-E7-A5-A6-A7-A8-A9-A8 and then capture at B6? If not, can you explain why? Thanks.
Good question Tan. After white play E7 in your sequence she’s ahead by one liberty in a capturing race. Black can keep taking liberties and connect along the left side, but white will have time to play E5 and E6 and will capture the four black stones.
There’s a way for black to save the four stones by trading for the corner or winning a capturing race (if white is stubborn). In some situations it could be better to connect along the edge and sacrifice the stones in the center. It would depend on the relative size of the corner and the isolated center group.
The point of this problem is just to show you that there’s a technique to save the four stones, but in a real game there are many more things to consider and (after seeing that black had these tesuji available) you’d still have to decide whether it was worth saving the four stones or not.
That’s one of the differences between practical play and the isolated world of Go problems
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