YES

1 decompositions
 #0 -----------
   1: +(x,0()) -> x
   2: +(s(x),y) -> s(+(y,x))
   3: +(x,y) -> +(y,x)

@Jouannaud and Kirchner's criterion
--- R
   1: +(x,0()) -> x
   2: +(s(x),y) -> s(+(y,x))
   3: +(x,y) -> +(y,x)

--- S
   1: +(x,0()) -> x
   2: +(s(x),y) -> s(+(y,x))
   3: +(x,y) -> +(y,x)