Certification Problem

Input (COPS 4)

We consider the TRS containing the following rules:

or(true,true) true (1)
or(x,y) or(y,x) (2)

The underlying signature is as follows:

{or/2, true/0}

Property / Task

Prove or disprove confluence.

Answer / Result

Yes.

Proof (by ACP @ CoCo 2021)

1 Strongly closed

Confluence is proven since the TRS is strongly closed. The joins can be performed using 2 step(s).