a
b
a
a
b
b
x1
a
a
b
a
b
b
a
x1
2.2
a
b
a
a
b
b
x1
a
b
a
b
b
a
x1
a
b
a
a
b
b
x1
a
b
b
a
x1
a
b
a
a
b
b
x1
a
a
b
a
b
b
a
x1
a
b
a
a
b
b
x1
a
x1
true
a
b
a
a
b
b
x1
a
x1
true
a
1
1
38
b
1
1
1
a
1
1
0
a
b
a
a
b
b
x1
a
a
b
a
b
b
a
x1
false
a
b
a
a
b
b
x1
a
b
b
a
x1
false
a
b
a
a
b
b
x1
a
b
a
b
b
a
x1
false
NaTT
certifiable-1.6