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