c
a
B
c
ab
Ac
aBC
BC
Ab
b
c
AB
Ac
B
bC
Ab

aB
B
a
aC
B
AB
B

C
bc

B
bc
AC
ABC
a
b
ac
AC
B
bC
b
C

aC
AbC

C
AC
bc


C
b

b
abc
a
abc

B
a
C
aB

A
Bc
C
AB
aBc
A
b

a
a
c
b
a
A
Ab
aC

B
C
Ab
Bc
A
Ac
c
B
AC
ABC
Ab
aC
bC


C
a

ABC
b
aB