a
b
b
a
x1
b
a
a
b
x1
b
a
b
x1
a
b
b
b
x1
2.2
b
a
b
x1
b
b
b
x1
a
b
b
a
x1
a
b
x1
a
b
b
a
x1
b
x1
a
b
b
a
x1
a
a
b
x1
b
a
b
x1
b
b
x1
b
a
b
x1
a
b
b
b
x1
a
b
b
a
x1
b
a
a
b
x1
true
a
b
b
a
x1
b
a
a
b
x1
b
a
b
x1
a
b
b
b
x1
b
a
b
x1
b
b
x1
a
b
b
a
x1
a
b
x1
a
b
b
a
x1
a
a
b
x1
a
b
b
a
x1
b
x1
b
a
b
x1
b
b
b
x1
true
a
1
1
11798
b
1
1
0
a
1
1
11798
b
1
1
0
a
b
b
a
x1
a
a
b
x1
b
a
b
x1
a
b
b
b
x1
a
b
b
a
x1
b
a
a
b
x1
a
b
b
a
x1
b
a
a
b
x1
b
a
b
x1
a
b
b
b
x1
a
b
b
a
x1
a
a
b
x1
a
b
b
a
x1
b
a
a
b
x1
b
a
b
x1
a
b
b
b
x1
true
2
1
a
1
0
0
1
0
1
0
0
b
1
0
1
0
0
1
1
0
a
1
0
0
1
0
1
0
0
b
1
0
0
0
1
1
1
0
b
a
b
x1
a
b
b
b
x1
a
b
b
a
x1
b
a
a
b
x1
a
b
b
a
x1
b
a
a
b
x1
b
a
b
x1
a
b
b
b
x1
a
b
b
a
x1
b
a
a
b
x1
b
a
b
x1
a
b
b
b
x1
true
Failed!
NaTT
certifiable-1.6