a
b
x1
b
c
a
x1
b
c
x1
c
b
b
x1
c
a
x1
a
c
x1
2.2
b
c
x1
b
b
x1
a
b
x1
b
c
a
x1
a
b
x1
c
a
x1
c
a
x1
c
x1
b
c
x1
b
x1
b
c
x1
c
b
b
x1
a
b
x1
a
x1
c
a
x1
a
c
x1
true
c
a
x1
a
c
x1
a
b
x1
a
x1
b
c
x1
c
b
b
x1
b
c
x1
b
x1
a
b
x1
b
c
a
x1
c
a
x1
c
x1
a
b
x1
c
a
x1
b
c
x1
b
b
x1
true
a
1
1
0
b
1
1
3
c
1
0
c
1
1
a
1
1
0
b
1
2
b
c
x1
b
b
x1
c
a
x1
c
x1
b
c
x1
b
x1
a
b
x1
b
c
a
x1
c
a
x1
a
c
x1
b
c
x1
c
b
b
x1
c
a
x1
c
x1
true
a
1
1
1
b
1
40651
c
1
1
0
c
1
1
1
a
1
1
0
b
1
2
a
b
x1
b
c
a
x1
c
a
x1
a
c
x1
b
c
x1
c
b
b
x1
b
c
x1
b
x1
b
c
x1
b
b
x1
true
2
1
a
1
0
0
1
1
1
1
0
b
1
1
0
1
c
1
1
0
0
0
1
1
0
c
1
0
0
a
1
0
0
b
1
1
0
0
0
1
0
0
a
b
x1
b
c
a
x1
c
a
x1
a
c
x1
b
c
x1
c
b
b
x1
NaTT
certifiable-1.6