a
x1
b
c
x1
a
b
x1
b
a
x1
d
c
x1
d
a
x1
a
c
x1
c
a
x1
2.2
d
c
x1
d
a
x1
d
c
x1
a
x1
a
b
x1
a
x1
a
c
x1
a
x1
true
d
c
x1
d
a
x1
true
a
1
1
1
d
1
0
b
1
1
c
1
1
2
d
1
1
0
a
1
0
a
c
x1
c
a
x1
a
x1
b
c
x1
a
b
x1
b
a
x1
d
c
x1
a
x1
false
a
c
x1
a
x1
a
b
x1
a
x1
true
a
1
1
1
d
1
0
b
1
1
1
c
1
1
0
d
1
1
0
a
1
1
0
a
c
x1
a
x1
a
c
x1
c
a
x1
a
x1
b
c
x1
a
b
x1
b
a
x1
a
c
x1
a
x1
true
a
1
1
1
d
1
0
b
1
1
c
1
1
7720
d
1
1
0
a
1
1
0
a
c
x1
c
a
x1
a
x1
b
c
x1
a
b
x1
b
a
x1
NaTT
certifiable-1.6