YES(?,O(n^1)) Problem: f(x,f(s(s(y)),f(z,w))) -> f(s(x),f(y,f(s(z),w))) L(f(s(s(y)),f(z,w))) -> L(f(s(0()),f(y,f(s(z),w)))) f(x,f(s(s(y)),nil())) -> f(s(x),f(y,f(s(0()),nil()))) Proof: Bounds Processor: bound: 0 enrichment: match automaton: final states: {5,4} transitions: f0(3,1) -> 4* f0(3,3) -> 4* f0(1,2) -> 4* f0(2,1) -> 4* f0(2,3) -> 4* f0(3,2) -> 4* f0(1,1) -> 4* f0(1,3) -> 4* f0(2,2) -> 4* s0(2) -> 1* s0(1) -> 1* s0(3) -> 1* L0(2) -> 5* L0(1) -> 5* L0(3) -> 5* 00() -> 2* nil0() -> 3* problem: Qed