a
c
d
x
c
x
u
b
d
d
x
b
x
v
a
a
x
u
v
x
v
a
c
x
u
b
d
x
v
c
x
b
x
w
a
a
x
u
w
x
w
a
c
x
u
b
d
x
w
c
x
b
x
2.2
w
a
a
x
w
x
v
a
c
x
u
b
d
x
v
a
a
x
v
x
w
a
c
x
u
b
d
x
w
a
a
x
u
w
x
v
a
a
x
u
v
x
true
v
a
a
x
v
x
true
a
1
1
1
d
1
0
v
1
0
w
1
0
b
1
0
u
1
0
u
1
0
w
1
0
c
1
0
v
1
1
0
a
1
0
v
a
a
x
u
v
x
false
v
a
c
x
u
b
d
x
false
w
a
a
x
w
x
true
a
1
1
1
d
1
0
v
1
0
w
1
1
0
b
1
0
u
1
0
u
1
0
w
1
0
c
1
0
v
1
0
a
1
0
w
a
a
x
u
w
x
false
w
a
c
x
u
b
d
x
false
NaTT
certifiable-1.6