Certification Problem

Input (COPS 354)

The rewrite relation of the following conditional TRS is considered.

pos(s(0)) true
pos(0) false
pos(s(x)) true | pos(x) ≈ true
pos(p(x)) false | pos(x) ≈ false

Property / Task

Prove or disprove confluence.

Answer / Result

Yes.

Proof (by ConCon @ CoCo 2020)

1 Almost-orthogonal

The given (extended) properly oriented, right-stable, oriented 3-CTRS is almost-orthogonal, since there are no conditional critical pairs.