%TITLE Longest mate in King and Bishop versus King and Bishop endgame: an endgame analysis by Joe Leslie-Hurd
%HEADING Longest mate in King and Bishop versus King and Bishop endgame
%SUBHEADING Mate in 1
%FOOTER An <a href="http://www.gilith/chess/endgames">endgame analysis</a> by <a href="http://www.gilith.com/">Joe Leslie-Hurd</a> on 16 February 2005.

[Event "Endgame analysis: longest mate in King and Queen versus King"]
[Site "Oxford ENG"]
[Date "2005.02.16"]
[Round "-"]
[White "Perfect"]
[Black "Perfect"]
[Result "1-0"]
[Time "05:00:12"]
[Annotator "Joe Leslie-Hurd"]
[WhiteType "program"]
[BlackType "program"]
[SetUp "1"]
[FEN "K7/1Q6/8/8/8/4k3/8/8 w - - 0 1"]

{Mate in 10 with Ka7, Kb8, Qa6, Qa7+, Qb1, Qb2, Qb3+, Qb4, Qb5, Qb6+, Qb8, Qc6, Qc7, Qc8, Qd5, Qd7, Qe7+, Qf7, Qg2, Qg7, Qh1 and Qh7. Worse are Qe4+ and Qf3+ which throw away the win.}
1. Ka7 {White mates in 9 after Kf4. Worse are Kd3, Kd4, Ke2 and Kf2 when White mates in 8, and Kd2 when White mates in 7.}
1... Kf4 {Mate in 9 with Kb6, Qb4+, Qd5, Qd7, Qe7, Qf7+, Qg2, Qh1 and Qh7. Worse are Ka6, Kb8, Qa6, Qa8, Qb1, Qb2, Qb3, Qb5, Qb6, Qb8+, Qc6, Qc7+, Qc8 and Qg7 with mate in 10, Ka8 with mate in 11, and Qe4+ and Qf3+ which throw away the win.}
2. Kb6 {White mates in 8 after Ke3. Worse are Ke5, Kf5, Kg3, Kg4 and Kg5 when White mates in 7.}
2... Ke3 {Mate in 8 with Kc5, Kc6, Qd5, Qd7, Qe7+, Qf7, Qg2, Qh1 and Qh7. Worse are Kb5, Kc7, Qa6, Qa7, Qa8, Qb8, Qc6, Qc7, Qc8 and Qg7 with mate in 9, Ka5, Ka6 and Ka7 with mate in 10, and Qe4+ and Qf3+ which throw away the win.}
3. Kc5 {White mates in 7 after Kf4. Worse are Ke2 and Kf2 when White mates in 6, and Kd2 and Kd3 when White mates in 5.}
3... Kf4 {Mate in 7 with Kd4, Kd5, Qb4+, Qd5, Qd7, Qe7, Qg2, Qh1 and Qh7. Worse are Kc4, Kc6, Kd6, Qa6, Qa7, Qa8, Qb1, Qb2, Qb3, Qb5, Qb6, Qb8+, Qc6, Qc7+, Qc8, Qf7+ and Qg7 with mate in 8, Kb4, Kb5 and Kb6 with mate in 9, and Qe4+ and Qf3+ which throw away the win.}
4. Kd4 {White mates in 6 after Kf5. Worse are Kg3, Kg4 and Kg5 when White mates in 5.}
4... Kf5 {Mate in 6 with Qa6, Qb6, Qc6, Qe7 and Qf7+. Worse are Kd5, Ke3, Qa8, Qb1+, Qb2, Qb3, Qb4, Qb5+, Qb8, Qc7, Qc8+, Qd5+, Qd7+, Qe4+, Qf3+, Qg2, Qg7, Qh1 and Qh7+ with mate in 7, and Kc3, Kc4, Kc5, Kd3 and Qa7 with mate in 8.}
5. Qf7+ {White mates in 5 after Kg4. Worse is Kg5 when White mates in 4.}
5... Kg4 {Mate in 5 with Kd3, Ke3, Ke4 and Qf6. Worse are Kd5, Ke5, Qd5, Qe6+, Qe7, Qe8, Qf1, Qf2, Qf8, Qg6+ and Qh7 with mate in 6, Kc3, Kc4, Kc5, Qa2, Qa7, Qb3, Qb7, Qc4, Qc7, Qd7+, Qg7+ and Qg8+ with mate in 7, and Qf3+, Qf4+, Qf5+ and Qh5+ which throw away the win.}
6. Ke4 {White mates in 4 after Kg3. Worse are Kg5, Kh3 and Kh4 when White mates in 3.}
6... Kg3 {Mate in 4 with Ke3, Qa2 and Qf3+. Worse are Ke5, Qa7, Qb3+, Qb7, Qc4, Qc7+, Qd5, Qd7, Qe6, Qe7, Qe8, Qf1, Qf4+, Qf5, Qf6, Qf8, Qg6+, Qg7+, Qg8+, Qh5 and Qh7 with mate in 5, Kd3, Kd4, Kd5 and Kf5 with mate in 6, and Qf2+ which throws away the win.}
7. Qa2 {White mates in 3 after Kg4 and Kh4. Worse is Kh3 when White mates in 2.}
7... Kg4 {Mate in 3 with Qg2+ and Qg8+. Worse are Qa1 and Qa7 with mate in 4, Qa3, Qa4, Qa5, Qa6, Qa8, Qb1, Qb2, Qb3, Qc2, Qc4, Qd2, Qd5, Qe2+, Qe6+, Qf2, Qf7 and Qh2 with mate in 5, Ke5 with mate in 6, Kd4, Kd5 and Ke3 with mate in 7, and Kd3 with mate in 8.}
8. Qg8+ {White mates in 2 after Kh3, Kh4 and Kh5.}
8... Kh4 {Mate in 2 with Kf4. Worse are Kf3, Kf5, Qg1, Qg2, Qg6 and Qg7 with mate in 3, Kd3, Kd4, Kd5, Ke3 and Ke5 with mate in 4, Qa2, Qa8, Qb3, Qb8, Qc4, Qc8, Qd5, Qd8+, Qe6, Qe8, Qf7, Qf8, Qh7+ and Qh8+ with mate in 5, and Qg3+, Qg4+ and Qg5+ which throw away the win.}
9. Kf4 {White mates in 1 after Kh3 and Kh5.}
9... Kh3 {Mate in 1 with Qg3#. Worse are Kf3, Qa2 and Qg1 with mate in 2, Ke3, Ke4, Qg4+, Qg5, Qg6 and Qg7 with mate in 3, Ke5, Kf5, Qa8, Qb3+, Qb8, Qc4, Qc8+, Qd5, Qd8, Qe6+, Qe8, Qf7, Qh7+ and Qh8+ with mate in 4, Qf8 with mate in 5, Kg5 with mate in 6, and Qg2+ which throws away the win.}
10. Qg3# {Checkmate.} 1-0
