Problem p198

한국어

within 3, 7 legal points

Black to play. Capture the marked white stones within 3 moves.

Stones to capture: A9, B9, C9, D9

Black to play.

Why this is the move

White has 7 possible answers. Every one of them is listed below with the way Black captures. These are search results, not written commentary.

  1. Black B8, White pass, Black C8, White pass, Black D8 (captures 4)
  2. Black B8, White C8, Black C7, White pass, Black D8 (captures 5)
  3. Black B8, White D8, Black C8, White pass, Black D7 (captures 5)
  4. Black B8, White A7, Black C8, White pass, Black D8 (captures 4)
  5. Black B8, White B7, Black C8, White pass, Black D8 (captures 4)
  6. Black B8, White C7, Black C8, White pass, Black D8 (captures 4)
  7. Black B8, White D7, Black C8, White pass, Black D8 (captures 4)

Black has 7 legal points here and exactly one of them captures. White answers the others as shown and survives.

  • Black C8, White answers at B8 and lives.
  • Black D8, White answers at B8 and lives.
  • Black A7, White survives even by passing.
  • Black B7, White survives even by passing.
  • Black C7, White survives even by passing.
  • Black D7, White survives even by passing.