YES(?,O(n^1)) Problem: f(x,a()) -> x f(x,g(y)) -> f(g(x),y) Proof: Bounds Processor: bound: 1 enrichment: match automaton: final states: {3} transitions: f1(4,2) -> 3* f1(4,1) -> 3* g1(2) -> 4* g1(4) -> 4* g1(1) -> 4* f0(1,2) -> 3* f0(2,1) -> 3* f0(1,1) -> 3* f0(2,2) -> 3* a0() -> 1* g0(2) -> 2* g0(1) -> 2* 1 -> 3* 2 -> 3* 4 -> 3* problem: Qed