Certification Problem
Input (TPDB Runtime_Complexity_Innermost_Rewriting/Der95/06)
The rewrite relation of the following TRS is considered.
f(g(x)) |
→ |
g(g(f(x))) |
(1) |
f(g(x)) |
→ |
g(g(g(x))) |
(2) |
The evaluation strategy is innermost.Property / Task
Determine bounds on the runtime complexity.Answer / Result
An upperbound for the complexity is O(n).Proof (by AProVE @ termCOMP 2023)
1 Bounds
The given TRS is
match-(raise)-bounded by 1.
This is shown by the following automaton.
-
final states:
{1, 2}
-
transitions:
f0(2) |
→ |
1 |
g1(5) |
→ |
1 |
g1(7) |
→ |
1 |
g0(2) |
→ |
2 |
g1(6) |
→ |
5 |
f1(2) |
→ |
6 |
g1(5) |
→ |
6 |
g1(7) |
→ |
6 |
g1(8) |
→ |
7 |
g1(2) |
→ |
8 |