YES(?,O(n^3)) TRS: { f mark X -> f X, f active X -> f X, g mark X -> g X, g active X -> g X, h mark X -> h X, h active X -> h X, mark f X -> active f mark X, mark g X -> active g X, mark h X -> active h mark X, active f X -> mark g h f X } DUP: We consider a non-duplicating system. Trs: { f mark X -> f X, f active X -> f X, g mark X -> g X, g active X -> g X, h mark X -> h X, h active X -> h X, mark f X -> active f mark X, mark g X -> active g X, mark h X -> active h mark X, active f X -> mark g h f X } Matrix Interpretation: Interpretation class: triangular [X2] [1 0 3][X2] [2] [active]([X1]) = [0 1 0][X1] + [0] [X0] [0 0 1][X0] [0] [X2] [1 3 3][X2] [1] [mark]([X1]) = [0 1 0][X1] + [0] [X0] [0 0 1][X0] [0] [X2] [1 0 0][X2] [0] [h]([X1]) = [0 1 2][X1] + [2] [X0] [0 0 0][X0] [0] [X2] [1 0 0][X2] [0] [g]([X1]) = [0 0 0][X1] + [3] [X0] [0 0 0][X0] [0] [X2] [1 0 0][X2] [0] [f]([X1]) = [0 1 3][X1] + [3] [X0] [0 0 0][X0] [3] Qed