f
X
cons
X
f
g
X
g
0
s
0
g
s
X
s
s
g
X
sel
0
cons
X
Y
X
sel
s
X
cons
Y
Z
sel
X
Z
2.2
g
s
X
g
X
f
X
f
g
X
sel
s
X
cons
Y
Z
sel
X
Z
f
X
g
X
true
sel
s
X
cons
Y
Z
sel
X
Z
true
s
1
1
1
f
1
0
0
0
0
sel
2
1
2
0
sel
2
0
f
1
0
g
1
0
cons
2
2
28958
g
1
0
f
X
f
g
X
true
Failed!
NaTT
certifiable-1.6