(0) Obligation:
Q restricted rewrite system:
The TRS R consists of the following rules:
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)
Q is empty.
(1) Overlay + Local Confluence (EQUIVALENT transformation)
The TRS is overlay and locally confluent. By [NOC] we can switch to innermost.
(2) Obligation:
Q restricted rewrite system:
The TRS R consists of the following rules:
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)
The set Q consists of the following terms:
isEmpty(empty)
isEmpty(node(x0, x1))
left(empty)
left(node(x0, x1))
right(empty)
right(node(x0, x1))
inc(0)
inc(s(x0))
count(x0, x1)
if(true, x0, x1, x2, x3, x4)
if(false, false, x0, x1, x2, x3)
if(false, true, x0, x1, x2, x3)
nrOfNodes(x0)
(3) DependencyPairsProof (EQUIVALENT transformation)
Using Dependency Pairs [AG00,LPAR04] we result in the following initial DP problem.
(4) Obligation:
Q DP problem:
The TRS P consists of the following rules:
INC(s(x)) → 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))
COUNT(n, x) → ISEMPTY(n)
COUNT(n, x) → ISEMPTY(left(n))
COUNT(n, x) → LEFT(n)
COUNT(n, x) → RIGHT(n)
COUNT(n, x) → LEFT(left(n))
COUNT(n, x) → RIGHT(left(n))
COUNT(n, x) → INC(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)
The TRS R consists of the following rules:
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)
The set Q consists of the following terms:
isEmpty(empty)
isEmpty(node(x0, x1))
left(empty)
left(node(x0, x1))
right(empty)
right(node(x0, x1))
inc(0)
inc(s(x0))
count(x0, x1)
if(true, x0, x1, x2, x3, x4)
if(false, false, x0, x1, x2, x3)
if(false, true, x0, x1, x2, x3)
nrOfNodes(x0)
We have to consider all minimal (P,Q,R)-chains.
(5) DependencyGraphProof (EQUIVALENT transformation)
The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 2 SCCs with 8 less nodes.
(6) Complex Obligation (AND)
(7) Obligation:
Q DP problem:
The TRS P consists of the following rules:
INC(s(x)) → INC(x)
The TRS R consists of the following rules:
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)
The set Q consists of the following terms:
isEmpty(empty)
isEmpty(node(x0, x1))
left(empty)
left(node(x0, x1))
right(empty)
right(node(x0, x1))
inc(0)
inc(s(x0))
count(x0, x1)
if(true, x0, x1, x2, x3, x4)
if(false, false, x0, x1, x2, x3)
if(false, true, x0, x1, x2, x3)
nrOfNodes(x0)
We have to consider all minimal (P,Q,R)-chains.
(8) Obligation:
Q DP problem:
The TRS P consists of the following rules:
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(false, false, n, m, x, y) → COUNT(m, x)
IF(false, true, n, m, x, y) → COUNT(n, y)
The TRS R consists of the following rules:
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)
The set Q consists of the following terms:
isEmpty(empty)
isEmpty(node(x0, x1))
left(empty)
left(node(x0, x1))
right(empty)
right(node(x0, x1))
inc(0)
inc(s(x0))
count(x0, x1)
if(true, x0, x1, x2, x3, x4)
if(false, false, x0, x1, x2, x3)
if(false, true, x0, x1, x2, x3)
nrOfNodes(x0)
We have to consider all minimal (P,Q,R)-chains.