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