Problem: +(0(),x) -> x +(+(x,y),z) -> +(x,+(y,z)) +(x,y) -> +(y,x) Proof: AT confluence processor Complete TRS T' of input TRS: +(0(),x) -> x +(x,0()) -> x +(+(x,y),z) -> +(x,+(y,z)) +(x,y) -> +(y,x) T' = (P union S) with TRS P:+(+(x,y),z) -> +(x,+(y,z)) +(x,y) -> +(y,x) TRS S:+(0(),x) -> x +(x,0()) -> x S is linear and P is reversible. CP(S,S) = 0() = 0() CP(S,P union P^-1) = +(y,z) = +(0(),+(y,z)), y = +(y,0()), +(y,z) = +(+(0(),y),z), +(x,z) = +(+(x,0()),z), x = +(x,0()), +(x,y) = +(x,+(y,0())), +(x,z) = +(x,+(0(),z)), x = +(0(),x), +(x,y) = +(+(x,y),0()), y = +(0(),y) CP(P union P^-1,S) = +(x188,+(x189,0())) = +(x188,x189), +(x,0()) = x, +(0(),x) = x, +(+(0(),x196),x197) = +(x196,x197) We have to check termination of S: Matrix Interpretation Processor: dim=1 interpretation: [+](x0, x1) = x0 + x1 + 5, [0] = 0 orientation: +(0(),x) = x + 5 >= x = x +(x,0()) = x + 5 >= x = x problem: Qed