image/svg+xml
a
1
b
1
a
2
b
2
a
3
b
3
a
3
a
2
a
1
c
3
c
1
c
2
b
1
b
2
b
3
a
3
a
2
a
1
c
3
c
1
c
2
b
1
b
2
b
3
a
3
a
2
a
1
c
3
c
1
c
2
b
1
b
2
b
3
a
3
a
2
a
1
c
3
c
1
c
2
b
1
b
2
b
3
a
3
a
2
a
1
c
3
c
1
c
2
b
1
b
2
b
3
s
exact
Tr
:
stg
⇒
sem
b
i
f
s
faithful
Tr
:
sem
⇒
stg
b
f
i
h
a
b
a
a
a
a
b
b
a
b
a
b
c
a
b
a
b
c
a
c
a
b
c
a
a
b
a
c
a
a
b
b
b
c
b
a
c
b
c
c
c
a
b
c
a
b
c
d
e
a
b
c
d
e
a
b
c
d
e
a
b
c
d
e
a
a
b
b
b
c
b
c
c
c
b
c
a
b
P
1
P
2
c
d
P
3
e