YES
O(n^2)
TRS:
 {
         .(x, 1()) -> x,
        .(x, i(x)) -> 1(),
  .(y, .(i(y), z)) -> z,
         .(1(), x) -> x,
        .(i(x), x) -> 1(),
  .(i(y), .(y, z)) -> z,
            i(1()) -> 1(),
           i(i(x)) -> x
 }
 Natural interpretation:
  Strict:
   {
           .(x, 1()) -> x,
          .(x, i(x)) -> 1(),
    .(y, .(i(y), z)) -> z,
           .(1(), x) -> x,
          .(i(x), x) -> 1(),
    .(i(y), .(y, z)) -> z,
              i(1()) -> 1(),
             i(i(x)) -> x
   }
  Weak:
   {}
  Interpretation class: deltarestricted
  [i](delta, X0) = + 1*X0 + 0 + 0*X0*delta + 1*delta
  [1](delta) = + 0 + 0*delta
  [.](delta, X1, X0) = + 1*X0 + 1*X1 + 0 + 0*X0*delta + 0*X1*delta + 1*delta
  i_tau_1(delta) = delta/(1 + 0 * delta)
  
  ._tau_1(delta) = delta/(1 + 0 * delta)._tau_2(delta) = delta/(1 + 0 * delta)
  
  Qed