1
1
1
1
3
6
B
C
C
C
C
D
D
D
D
D
D
E
E
E
E
E
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F