YES TRS: active(f(f(X))) -> mark(c(f(g(f(X))))) active(c(X)) -> mark(d(X)) active(h(X)) -> mark(c(d(X))) active(f(X)) -> f(active(X)) active(h(X)) -> h(active(X)) f(mark(X)) -> mark(f(X)) h(mark(X)) -> mark(h(X)) proper(f(X)) -> f(proper(X)) proper(c(X)) -> c(proper(X)) proper(g(X)) -> g(proper(X)) proper(d(X)) -> d(proper(X)) proper(h(X)) -> h(proper(X)) f(ok(X)) -> ok(f(X)) c(ok(X)) -> ok(c(X)) g(ok(X)) -> ok(g(X)) d(ok(X)) -> ok(d(X)) h(ok(X)) -> ok(h(X)) top(mark(X)) -> top(proper(X)) top(ok(X)) -> top(active(X)) max/plus interpretations on N: active_A(x1) = max{1, 17} active#_A(x1) = max{46, 37 + x1} f_A(x1) = max{5, x1} f#_A(x1) = max{33, 43} mark_A(x1) = max{3, 17} mark#_A(x1) = max{32, 34} c_A(x1) = max{5, x1} c#_A(x1) = max{27, 27} g_A(x1) = max{4, x1} g#_A(x1) = max{34, 17} d_A(x1) = max{1, x1} d#_A(x1) = max{0, 1 + x1} h_A(x1) = max{8, x1} h#_A(x1) = max{33, 36} proper_A(x1) = max{8, 4} proper#_A(x1) = max{35, 44} ok_A(x1) = max{26, 18 + x1} ok#_A(x1) = max{27, 18} top_A(x1) = max{0, 1} top#_A(x1) = max{29, 27 + x1} precedence: top > active = proper > f > mark = g > c = d = h > ok