Problem p200

한국어

within 3, 5 legal points

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

Stones to capture: A9, B9, A8, B8, C8

Black to play.

Why this is the move

White has 4 possible answers. Every one of them is listed below with the way Black captures. These are search results, not written commentary.

  1. Black D8, White pass, Black A7, White pass, Black C9 (captures 5)
  2. Black D8, White C9, Black D9, White pass, Black A7 (captures 6)
  3. Black D8, White D9, Black C9, White pass, Black A7 (captures 5)
  4. Black D8, White A7, Black C9 (captures 6)

Black has 5 legal points here and exactly one of them captures. White answers the others as shown and survives.

  • Black C9, White survives even by passing.
  • Black D9, White survives even by passing.
  • Black A7, White answers at D8 and lives.
  • Black D7, White survives even by passing.