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