8
1
6
1
5
7
2
3
9
4
6
7
8
3
9
4
6
4
1
6
6
2
3
1
7
9
6
5
3
9
6
5
4
"The essence of chess is thinking about what chess is." — David Bronstein
"The essence of chess is thinking about what chess is." — David Bronstein
"Problems worthy of attack prove their worth by fighting back." — Piet Hein
"Problems worthy of attack prove their worth by fighting back." — Piet Hein