NO

Problem:
 +(x,0()) -> x
 +(x,s(y)) -> s(+(x,y))
 +(+(x,y),z) -> +(x,+(y,z))
 +(x,y) -> +(y,x)

Proof:
 Containment Processor: loop length: 1
                        terms:
                         +(x,y)
                        context: []
                        substitution:
                         x -> y
                         y -> x
  Qed