min
0
y
0
min
s
x
0
0
min
s
x
s
y
min
x
y
len
nil
0
len
cons
x
xs
s
len
xs
sum
x
0
x
sum
x
s
y
s
sum
x
y
le
0
x
true
le
s
x
0
false
le
s
x
s
y
le
x
y
take
0
cons
y
ys
y
take
s
x
cons
y
ys
take
x
ys
addList
x
y
if
le
0
min
len
x
len
y
0
x
y
nil
if
false
c
x
y
z
z
if
true
c
xs
ys
z
if
le
s
c
min
len
xs
len
ys
s
c
xs
ys
cons
sum
take
c
xs
take
c
ys
z
2.2
addList
x
y
le
0
min
len
x
len
y
take
s
x
cons
y
ys
take
x
ys
if
true
c
xs
ys
z
min
len
xs
len
ys
len
cons
x
xs
len
xs
if
true
c
xs
ys
z
if
le
s
c
min
len
xs
len
ys
s
c
xs
ys
cons
sum
take
c
xs
take
c
ys
z
if
true
c
xs
ys
z
le
s
c
min
len
xs
len
ys
if
true
c
xs
ys
z
len
xs
sum
x
s
y
sum
x
y
min
s
x
s
y
min
x
y
addList
x
y
len
y
if
true
c
xs
ys
z
take
c
xs
if
true
c
xs
ys
z
sum
take
c
xs
take
c
ys
addList
x
y
min
len
x
len
y
addList
x
y
if
le
0
min
len
x
len
y
0
x
y
nil
le
s
x
s
y
le
x
y
if
true
c
xs
ys
z
len
ys
addList
x
y
len
x
if
true
c
xs
ys
z
take
c
ys
true
addList
x
y
len
x
false
addList
x
y
if
le
0
min
len
x
len
y
0
x
y
nil
false
addList
x
y
min
len
x
len
y
false
if
true
c
xs
ys
z
if
le
s
c
min
len
xs
len
ys
s
c
xs
ys
cons
sum
take
c
xs
take
c
ys
z
true
Failed!
NaTT
certifiable-1.6