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