Weekly Go problems: Week 36

Here are the weekly Go problems for week 36.

Black plays first in all problems and all solutions are labeled ‘correct’. Have fun!

Easy Go problem

Sometimes you need to play in a way that prevents your partner from sacrificing stones.

ggg easy 36 picture

Download the solutions to the easy problem as an SGF or PDF file.

 

Intermediate Go problem

It looks like white A was a bit too greedy. Time to school white.

ggg intermediate 36 picture

Download the solutions to the intermediate problem as an SGF or PDF file.

 

Hard Go problem

Don’t be seduced by the obvious. Ask the relevant questions first…

go problems 36 picture

Download the solutions to the hard problem as an SGF or PDF file.

Still want more Go problems?

You can find Go books packed full of life and death problems, tesuji problems and other valuable Go knowledge at the Go Game Shop.

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

David likes teaching, learning, playing and writing about the game Go. He's taught hundreds of people to play Go, including many children at schools in Australia. In 2010 David was the Australian representative at the 31st World Amateur Go Championships. He's a 5 dan amateur Go player and is the editor of Go Game Guru. You can find David on Google+ and follow Go Game Guru on Facebook, Google+ or Twitter.

Comments

  1. Damián says:

    Today problems are all beautifull.
    - The easy one is enlightening for beginners.
    - The intermediate and hard are greate because it forces you to think in priorities.

    I don’t want to say anymore because of the spoilers, but thanks a lot.

    Damián

  2. Doing go problems before maturity exam is immature, but the desire to solve the hard one was stronger than common sense. ;)

    • David Ormerod says:

      I don’t know, it gets to a point where you can’t study much more and solving Go problems can be quite relaxing.

      I hope your exam goes well.

  3. It was almost like cheating. For the hard one, I started with B3 and got the hint. Then I knew I needed to win the liberty race and got to the answer right away. It was fun! But I guess I am still far from 1k. (I hope I did not give out too much hint here)

  4. nice problems

  5. The hard problem is a really interesting example of how to generate a lack of liberties.

    • David Ormerod says:

      Yes, there’s a very similar situation where you can do this in the center to setup a spiral ladder (squeeze and ladder) situation. The move order matters there too, it doesn’t happen very often in games though. I’ll see if I can remember how to setup that shape for another week.

  6. Thanks again for the nice problems!

    For the hard problem, the only variation that seemingly needs the funny looking White stone up the left side at C10 is the supposed “ko” from:
    B3 B4 B1 C2 A2 C4 A5 A4 A3 A6 C5 B7

    However, even without the C10 White stone, Black has at best an unfavorable many-step ko, i.e., White for all practical situations is alive.

    Of course, somewhere else on the board, Black could have an infinite supply of ko threats from a double ko. But if Black is allowed to have a double ko, then any problem status involving ko would be invalid.

    So, isn’t the White stone at C10 effectively extraneous?

    • David Ormerod says:

      Right Myron, the problem more or less works without that ‘book keeping’ stone.

      I added it because; firstly it’s something else for some readers to think about (more like a real game) and, secondly I’ve found over the course of doing these weekly problems that it’s better to remove all ambiguity where possible. There are enough Go Game Guru readers that someone always finds a variation otherwise.

      Sometimes I reject problems when I find they have too many possible solutions. This isn’t really one of those cases because the correct solution is so much better (as you say), but according to my reading C10 still makes sure that every other sequence, except for the correct one, fails completely.

  7. jangalf says:

    Thanks for the Problems David, the intermediate one is very beautiful and has a suprising solution. I can’t solve the hard one yet.

    • David Ormerod says:

      You’re welcome Jangalf. With the hard one, if you can see why striking at the vital point fails, then think about how you could reduce white’s liberties in the final shape and do that first.

  8. Vladimir Levin says:

    How hard is the “hard” problem do you think? I was able to understand the solution but finding that seems to be a bit beyond me.

    • David Ormerod says:

      I’m not sure Vlad and I’m probably the wrong person to ask since I have no idea how people go about rating the difficulty of problems.

      If you want me to guess, based on feeling, I’d say that a low kyu/dan player should be able to solve this one with a bit of thinking. This problem is less about being able to read deeply and more about a certain way of thinking, which you can learn. It’s not as hard as some of the problems from other weeks.

  9. I can tell you that the hard problem does not come intuitive at all to me and I’m an EGF 2d, though probably in decline, since I’m KGS 1d and find it hard to solve these problems at times.

    The intermediate problem does come intuitive to me, as the tesjui for this compromised diagonal has been hard wired in my brain.

    I finally found the solution not because I knew I had to reduce liberties, but because an unsolvable problem where the xy-point is open often unlocks when thinking of that proverb “Strange things happen at the xy-point”. I would not see this in a game situation.

    Great work, David, as always.

    BTW: in the basic one you could also apply the 1-2-3 principle, which yields another correct solution.

  10. Guillaume says:

    About the easy one.
    There’s a small variation that is not labeled correct (not labeled at all).. It was the 1st one I tried :)
    Black B1 – White C1 – Black A2 you don’t need to do the atari since white can’t come at B2 to make you eyes false.. so it leaves you with a small ko threat for Black at B2 (atari on 4 White’s stones).
    I doesn’t really mater for beginners but it can make a difference in a close game, I think.

    Thank you again for these problems!

  11. Guillaume says:

    BTW — It would be nice to have a way to modify an already posted message.. I mean, I’m french and I don’t speak english very often so I do make some mistakes or write a word incorrectly like in my previous post.. I would be glad to have the possibility of correcting them so that it won’t stay on the internet that my english is bad :)

  12. Guillaume says:

    In the hard problem there’s a way to obtain this answer:
    End of variation
    Correct. White lost a liberty when she played A. She should play the ko instead.

    Why is White a woman? :) First time I see he/she and not simply White with no gender :)

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