isEmpty
empty
true
isEmpty
node
l
r
false
left
empty
empty
left
node
l
r
l
right
empty
empty
right
node
l
r
r
inc
0
s
0
inc
s
x
s
inc
x
count
n
x
if
isEmpty
n
isEmpty
left
n
right
n
node
left
left
n
node
right
left
n
right
n
x
inc
x
if
true
b
n
m
x
y
x
if
false
false
n
m
x
y
count
m
x
if
false
true
n
m
x
y
count
n
y
nrOfNodes
n
count
n
0
isEmpty
1
empty
0
true
0
node
2
false
0
left
1
right
1
inc
1
0
0
s
1
count
2
if
6
nrOfNodes
1
INNERMOST
./TRS/secret06/aprove/nrOfNodes.trs