Termination Proof Script
Consider the TRS R consisting of the rewrite rules
|
1: |
|
0(#) |
→ # |
2: |
|
x + # |
→ x |
3: |
|
# + x |
→ x |
4: |
|
0(x) + 0(y) |
→ 0(x + y) |
5: |
|
0(x) + 1(y) |
→ 1(x + y) |
6: |
|
1(x) + 0(y) |
→ 1(x + y) |
7: |
|
1(x) + 1(y) |
→ 0((x + y) + 1(#)) |
8: |
|
(x + y) + z |
→ x + (y + z) |
9: |
|
# * x |
→ # |
10: |
|
0(x) * y |
→ 0(x * y) |
11: |
|
1(x) * y |
→ 0(x * y) + y |
12: |
|
(x * y) * z |
→ x * (y * z) |
13: |
|
sum(nil) |
→ 0(#) |
14: |
|
sum(cons(x,l)) |
→ x + sum(l) |
15: |
|
prod(nil) |
→ 1(#) |
16: |
|
prod(cons(x,l)) |
→ x * prod(l) |
|
There are 21 dependency pairs:
|
17: |
|
0(x) +# 0(y) |
→ 0#(x + y) |
18: |
|
0(x) +# 0(y) |
→ x +# y |
19: |
|
0(x) +# 1(y) |
→ x +# y |
20: |
|
1(x) +# 0(y) |
→ x +# y |
21: |
|
1(x) +# 1(y) |
→ 0#((x + y) + 1(#)) |
22: |
|
1(x) +# 1(y) |
→ (x + y) +# 1(#) |
23: |
|
1(x) +# 1(y) |
→ x +# y |
24: |
|
(x + y) +# z |
→ x +# (y + z) |
25: |
|
(x + y) +# z |
→ y +# z |
26: |
|
0(x) *# y |
→ 0#(x * y) |
27: |
|
0(x) *# y |
→ x *# y |
28: |
|
1(x) *# y |
→ 0(x * y) +# y |
29: |
|
1(x) *# y |
→ 0#(x * y) |
30: |
|
1(x) *# y |
→ x *# y |
31: |
|
(x * y) *# z |
→ x *# (y * z) |
32: |
|
(x * y) *# z |
→ y *# z |
33: |
|
SUM(nil) |
→ 0#(#) |
34: |
|
SUM(cons(x,l)) |
→ x +# sum(l) |
35: |
|
SUM(cons(x,l)) |
→ SUM(l) |
36: |
|
PROD(cons(x,l)) |
→ x *# prod(l) |
37: |
|
PROD(cons(x,l)) |
→ PROD(l) |
|
The approximated dependency graph contains 4 SCCs:
{18-20,22-25},
{27,30-32},
{37}
and {35}.
-
Consider the SCC {18-20,22-25}.
The usable rules are {1-8}.
The constraints could not be solved.
-
Consider the SCC {27,30-32}.
The usable rules are {1-12}.
The constraints could not be solved.
-
Consider the SCC {37}.
There are no usable rules.
By taking the AF π with
π(PROD) = 1
and π(cons) = [2] together with
the lexicographic path order with
empty precedence,
rule 37
is strictly decreasing.
-
Consider the SCC {35}.
There are no usable rules.
By taking the AF π with
π(SUM) = 1
and π(cons) = [2] together with
the lexicographic path order with
empty precedence,
rule 35
is strictly decreasing.
Tyrolean Termination Tool (0.07 seconds)
--- May 4, 2006