10 10 20
0 0 0 0 0 0 0 0 8 0
0 0 0 0 0 0 0 0 8 0
b 3 0
a 9 0
b 8 0
a 8 0
a 3 0
b 9 0
b 6 8
b 6 0
b 5 8
b 5 0
b 6 8
b 6 0
a 5 8
b 9 8
a 5 8
b 5 0
a 5 0
a 9 8
b 1 8
a 1 8