Hopefully I won't make a fool of myself. I've only been playing for ~4 days and so this probably all seems very basic and easy to you guys
. Go easy on me 
!Here is the ending position of a game I played against the 9kyu level of Many Faces of Go Version 12:
Now, after my move 55 as shown in the diagram, white (the computer) passed his turn 56. What is best for me to play as my move 57 once he's passed? The sequence:
57. A2
58. A5
59. C9
60. D9
61. B9
looks good at first for me to get seki in the top left but then white can reply with 62. A1! and my black group is dead. I can certainly improve the position after move 56 (pass) a little by playing 57. A2 58. A5 59. A1 but then my attack in the top left is reduced to nothing after 60. B9.
So, what's my best move 57 and continuation? I'm aware that I've won the game, I'm just trying to consider what would be the way for me to secure the most points, as I think this kind of thinking would benefit me in a larger, more complex game.
Also, as a follow on question, if the A1 and A2 squares were both black stones instead of in the diagram, and white played 1. A5 in that situation, then I can get seki by playing 2. C9 3. D9 4. B9? However, if white replied to 2. C9 with 3. B9, then I must reply 4. D9 instead of 4. A9 which would kill my group, and if I replied 4. D9, it's seki after 5. E9 6. C9 7. D9, I think?
Thanks a lot, comments are much appreciated
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