Certification Problem

Input (TPDB TRS_Standard/Various_04/07)

The rewrite relation of the following TRS is considered.

f(x,y) h(x,y) (1)
f(x,y) h(y,x) (2)
h(x,x) x (3)

Property / Task

Prove or disprove termination.

Answer / Result

Yes.

Proof (by ttt2 @ termCOMP 2023)

1 Rule Removal

Using the Weighted Path Order with the following precedence and status
prec(h) = 0 status(h) = [2, 1] list-extension(h) = Lex
prec(f) = 1 status(f) = [2, 1] list-extension(f) = Lex
and the following Max-polynomial interpretation
[h(x1, x2)] = max(1, 1 + 1 · x1, 1 + 1 · x2)
[f(x1, x2)] = max(0, 1 + 1 · x1, 1 + 1 · x2)
all of the following rules can be deleted.
f(x,y) h(x,y) (1)
f(x,y) h(y,x) (2)
h(x,x) x (3)

1.1 R is empty

There are no rules in the TRS. Hence, it is terminating.