active
zeros
mark
cons
0
zeros
active
and
tt
X
mark
X
active
length
nil
mark
0
active
length
cons
N
L
mark
s
length
L
active
take
0
IL
mark
nil
active
take
s
M
cons
N
IL
mark
cons
N
take
M
IL
active
cons
X1
X2
cons
active
X1
X2
active
and
X1
X2
and
active
X1
X2
active
length
X
length
active
X
active
s
X
s
active
X
active
take
X1
X2
take
active
X1
X2
active
take
X1
X2
take
X1
active
X2
cons
mark
X1
X2
mark
cons
X1
X2
and
mark
X1
X2
mark
and
X1
X2
length
mark
X
mark
length
X
s
mark
X
mark
s
X
take
mark
X1
X2
mark
take
X1
X2
take
X1
mark
X2
mark
take
X1
X2
proper
zeros
ok
zeros
proper
cons
X1
X2
cons
proper
X1
proper
X2
proper
0
ok
0
proper
and
X1
X2
and
proper
X1
proper
X2
proper
tt
ok
tt
proper
length
X
length
proper
X
proper
nil
ok
nil
proper
s
X
s
proper
X
proper
take
X1
X2
take
proper
X1
proper
X2
cons
ok
X1
ok
X2
ok
cons
X1
X2
and
ok
X1
ok
X2
ok
and
X1
X2
length
ok
X
ok
length
X
s
ok
X
ok
s
X
take
ok
X1
ok
X2
ok
take
X1
X2
top
mark
X
top
proper
X
top
ok
X
top
active
X
2.2
active
take
s
M
cons
N
IL
cons
N
take
M
IL
active
length
cons
N
L
s
length
L
top
ok
X
top
active
X
take
ok
X1
ok
X2
take
X1
X2
length
mark
X
length
X
active
and
X1
X2
active
X1
proper
s
X
proper
X
s
mark
X
s
X
active
length
X
active
X
active
and
X1
X2
and
active
X1
X2
s
ok
X
s
X
proper
length
X
length
proper
X
active
take
X1
X2
take
X1
active
X2
top
mark
X
proper
X
top
mark
X
top
proper
X
take
X1
mark
X2
take
X1
X2
active
take
X1
X2
active
X2
proper
take
X1
X2
take
proper
X1
proper
X2
and
mark
X1
X2
and
X1
X2
top
ok
X
active
X
cons
ok
X1
ok
X2
cons
X1
X2
active
cons
X1
X2
active
X1
active
take
X1
X2
take
active
X1
X2
active
zeros
cons
0
zeros
proper
length
X
proper
X
proper
take
X1
X2
proper
X2
active
length
X
length
active
X
active
length
cons
N
L
length
L
proper
and
X1
X2
proper
X2
active
s
X
active
X
take
mark
X1
X2
take
X1
X2
proper
and
X1
X2
proper
X1
proper
cons
X1
X2
proper
X1
proper
take
X1
X2
proper
X1
active
cons
X1
X2
cons
active
X1
X2
proper
and
X1
X2
and
proper
X1
proper
X2
proper
s
X
s
proper
X
active
s
X
s
active
X
proper
cons
X1
X2
cons
proper
X1
proper
X2
active
take
s
M
cons
N
IL
take
M
IL
and
ok
X1
ok
X2
and
X1
X2
active
take
X1
X2
active
X1
length
ok
X
length
X
cons
mark
X1
X2
cons
X1
X2
proper
cons
X1
X2
proper
X2
true
top
mark
X
top
proper
X
top
ok
X
top
active
X
true
Failed!
NaTT
certifiable-1.6