a
b
x1
b
r
x1
r
a
x1
d
r
x1
r
x1
d
x1
d
a
x1
a
a
d
x1
d
x1
a
x1
2.2
r
a
x1
r
x1
d
a
x1
a
a
d
x1
d
a
x1
a
d
x1
a
b
x1
r
x1
d
x1
a
x1
r
a
x1
d
r
x1
d
a
x1
d
x1
r
x1
d
x1
true
r
x1
d
x1
d
a
x1
d
x1
r
a
x1
d
r
x1
d
x1
a
x1
d
a
x1
a
a
d
x1
a
b
x1
r
x1
d
a
x1
a
d
x1
r
a
x1
r
x1
true
a
1
1
0
d
1
1
0
b
1
1
3
r
1
1
0
d
1
1
1
r
1
1
2
a
1
1
0
r
a
x1
r
x1
d
a
x1
d
x1
d
a
x1
a
a
d
x1
a
b
x1
b
r
x1
r
x1
d
x1
d
x1
a
x1
r
a
x1
d
r
x1
d
a
x1
d
x1
true
a
1
1
1
d
1
0
b
1
0
r
1
0
d
1
1
0
r
1
0
a
1
0
r
a
x1
r
x1
true
a
1
1
8367
d
1
8366
b
1
1
3
r
1
0
d
1
1
r
1
1
2
a
1
0
NaTT
certifiable-1.6