1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
4
5
5
5
6
7
9
A
B
B
C
C
D
D
D
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