1
1
1
1
2
2
3
5
5
6
6
9
9
9
B
C
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