Certification Problem

Input (COPS 579)

We consider the TRS containing the following rules:

+(x,0) x (1)
+(x,s(y)) s(+(x,y)) (2)
-(0,x) 0 (3)
-(x,0) x (4)
-(s(x),s(y)) -(x,y) (5)

The underlying signature is as follows:

{+/2, 0/0, s/1, -/2}

Property / Task

Prove or disprove confluence.

Answer / Result

Yes.

Proof (by ACP @ CoCo 2020)

1 Strongly closed

Confluence is proven since the TRS is strongly closed. The joins can be performed using 0 step(s).