YES TRS: active(first(0(),X)) -> mark(nil()) active(first(s(X),cons(Y,Z))) -> mark(cons(Y,first(X,Z))) active(from(X)) -> mark(cons(X,from(s(X)))) mark(first(X1,X2)) -> active(first(mark(X1),mark(X2))) mark(0()) -> active(0()) mark(nil()) -> active(nil()) mark(s(X)) -> active(s(mark(X))) mark(cons(X1,X2)) -> active(cons(mark(X1),X2)) mark(from(X)) -> active(from(mark(X))) first(mark(X1),X2) -> first(X1,X2) first(X1,mark(X2)) -> first(X1,X2) first(active(X1),X2) -> first(X1,X2) first(X1,active(X2)) -> first(X1,X2) s(mark(X)) -> s(X) s(active(X)) -> s(X) cons(mark(X1),X2) -> cons(X1,X2) cons(X1,mark(X2)) -> cons(X1,X2) cons(active(X1),X2) -> cons(X1,X2) cons(X1,active(X2)) -> cons(X1,X2) from(mark(X)) -> from(X) from(active(X)) -> from(X) max/plus interpretations on N: active_A(x1) = max{64, x1} active#_A(x1) = max{52, -31 + x1} first_A(x1,x2) = max{97, 48 + x1, 56 + x2} first#_A(x1,x2) = max{84, 84, 48} 0_A = 26 0#_A = 86 mark_A(x1) = max{37, 38 + x1} mark#_A(x1) = max{53, 7 + x1} nil_A = 37 nil#_A = 85 s_A(x1) = max{32, 48 + x1} s#_A(x1) = max{0, -38 + x1} cons_A(x1,x2) = max{43, 40 + x1, 58} cons#_A(x1,x2) = max{51, 8 + x1, 55} from_A(x1) = max{127, 88 + x1} from#_A(x1) = max{54, 56} precedence: first = 0 > nil > mark > active > s > from > cons