Xuanxuan Qijing · Problem 20
Xuanxuan Qijing · Problem 20. Go, Black to play. Study 11 reference plies, try both sides and branch from the replay.
Site coordinates run A–S left to right and 1–19 top to bottom; A1 is the top-left intersection.
Read the position, one decision at a time
Try the position first, then open the notes. They explain measurable changes in the reference, not every possible variation.
Reveal step-by-step explanations
1. Black · M18
This move captures 0 stones. After captures, the connected group containing the new stone has 3 stones and 3 liberties: M19, L18, N18. Diagonal neighbours are not part of the same group. More than one liberty does not by itself establish life; examine the next move.
2. White · N19
This move captures 0 stones. After captures, the connected group containing the new stone has 1 stones and 3 liberties: N18, M19, O19. Diagonal neighbours are not part of the same group. More than one liberty does not by itself establish life; examine the next move.
3. Black · O19
This move captures 0 stones. After captures, the connected group containing the new stone has 1 stones and 2 liberties: O18, P19. Diagonal neighbours are not part of the same group. More than one liberty does not by itself establish life; examine the next move.
4. White · O18
This move captures 0 stones. After captures, the connected group containing the new stone has 4 stones and 3 liberties: N18, P19, Q18. Diagonal neighbours are not part of the same group. More than one liberty does not by itself establish life; examine the next move.
Understand this position
19 ranks × 19 files · 7 black stones · 7 white stones
Count the liberties of each connected group, not the empty points next to just one stone. Orthogonal contact connects; diagonal contact does not. Try your move, count captures and recount the resulting group’s liberties before comparing the reference.
Read the reference line (11 plies)
Coordinates match this board: letters left to right, row numbers from top to bottom. These are board coordinates, not traditional score notation.
- Black
M18 - White
N19 - Black
O19 - White
O18 - Black
K18 - White
J18 - Black
L19 - White
J19 - Black
N18 - White
K19 - Black
Q18