YES(?,O(n^2))
TRS:
 {
    +(0(), y) -> y,
    +(s x, y) -> s +(x, y),
    -(x, 0()) -> x,
    -(0(), y) -> 0(),
  -(s x, s y) -> -(x, y)
 }
 DUP: We consider a non-duplicating system.
  Trs:
   {
      +(0(), y) -> y,
      +(s x, y) -> s +(x, y),
      -(x, 0()) -> x,
      -(0(), y) -> 0(),
    -(s x, s y) -> -(x, y)
   }
  Matrix Interpretation:
   Interpretation class: triangular
       [X3]  [X1]    [1 1][X3]   [1 3][X1]   [0]
   [-]([X2], [X0]) = [0 1][X2] + [0 1][X0] + [3]
   
       [X1]    [1 0][X1]   [2]
   [s]([X0]) = [0 1][X0] + [3]
   
         [1]
   [0] = [3]
   
       [X3]  [X1]    [1 1][X3]   [1 0][X1]   [0]
   [+]([X2], [X0]) = [0 1][X2] + [0 1][X0] + [1]
   
   
   Qed