YES(?,O(n^1)) Problem: b(b(b(a(b(a(b(b(a(b(x1)))))))))) -> b(b(a(b(a(b(b(b(a(b(a(b(b(x1))))))))))))) Proof: Bounds Processor: bound: 0 enrichment: match automaton: final states: {2} transitions: b0(1) -> 2* a0(1) -> 1* problem: Qed