double
0
0
double
s
x
s
s
double
x
del
x
nil
nil
del
x
cons
y
xs
if
eq
x
y
x
y
xs
if
true
x
y
xs
xs
if
false
x
y
xs
cons
y
del
x
xs
eq
0
0
true
eq
0
s
y
false
eq
s
x
0
false
eq
s
x
s
y
eq
x
y
first
nil
0
first
cons
x
xs
x
doublelist
nil
nil
doublelist
cons
x
xs
cons
double
x
doublelist
del
first
cons
x
xs
cons
x
xs
2.2
if
false
x
y
xs
del
x
xs
doublelist
cons
x
xs
first
cons
x
xs
del
x
cons
y
xs
eq
x
y
eq
s
x
s
y
eq
x
y
doublelist
cons
x
xs
del
first
cons
x
xs
cons
x
xs
doublelist
cons
x
xs
double
x
double
s
x
double
x
del
x
cons
y
xs
if
eq
x
y
x
y
xs
doublelist
cons
x
xs
doublelist
del
first
cons
x
xs
cons
x
xs
true
doublelist
cons
x
xs
doublelist
del
first
cons
x
xs
cons
x
xs
true
Failed!
NaTT
certifiable-1.6