Xuanxuan Qijing Problem 90: Black to play and connect
玄玄棋经 · Problem 90 of 347 · First-line placement to connect underneath
Black's three stones on the right are cut off, and the white stones that separate them from the left are not strong either. Pushing at them directly only makes them stronger. Look at the first line.
How to solve it
Black's three stones on the top side are cut off from the left by a line of white stones. Black starts with the placement at F19 on the first line, underneath those stones.
If White plays D18, Black extends along the first line to G19. White attacks from the right with K18, and Black fixes the left side with D17 and, after White's E18, with C18.
White throws in at H19, Black captures with J19, and White blocks at K19. Black then plays D19, and the stones on the first line work together: Sensei's Library gives this as Black connecting, and KataGo agrees that the white stones in the middle are lost.
If White blocks the first move at G19, Black cuts at E18. White plays D18 and Black connects at D17. The white stones are sealed in with fewer liberties than Black's three stones, so Black wins the race.
Main line
- 1. Black F19
- 2. White D18
- 3. Black G19
- 4. White K18
- 5. Black D17
- 6. White E18
- 7. Black C18
- 8. White H19
- 9. Black J19
- 10. White K19
- 11. Black D19
Solution checked against Sensei's Library.
Play it out on the board
Place the stones yourself and see the refutation when you miss. All the Xuanxuan Qijing problems as quick lessons.