YES(?,O(n^1)) Problem: f(c(X,s(Y))) -> f(c(s(X),Y)) g(c(s(X),Y)) -> f(c(X,s(Y))) Proof: Bounds Processor: bound: 2 enrichment: match automaton: final states: {4,3,2,1} transitions: f1(12) -> 4* f1(7) -> 1* c1(19,2) -> 12* c1(19,4) -> 12* c1(4,6) -> 12* c1(6,2) -> 7* c1(6,4) -> 7* c1(1,6) -> 12* c1(3,6) -> 12* c1(19,1) -> 12* c1(19,3) -> 12* c1(6,1) -> 7* c1(6,3) -> 7* c1(2,6) -> 12* s1(15) -> 19* s1(2) -> 6* s1(19) -> 19* s1(4) -> 6* s1(6) -> 6* s1(1) -> 6* s1(3) -> 6* f2(16) -> 4* c2(15,1) -> 16* c2(15,3) -> 16* c2(15,2) -> 16* c2(15,4) -> 16* c2(15,6) -> 16* f0(2) -> 1* f0(4) -> 1* f0(1) -> 1* f0(3) -> 1* s2(15) -> 15* s2(2) -> 15* s2(4) -> 15* s2(1) -> 15* s2(3) -> 15* c0(3,1) -> 2* c0(3,3) -> 2* c0(4,2) -> 2* c0(4,4) -> 2* c0(1,2) -> 2* c0(1,4) -> 2* c0(2,1) -> 2* c0(2,3) -> 2* c0(3,2) -> 2* c0(3,4) -> 2* c0(4,1) -> 2* c0(4,3) -> 2* c0(1,1) -> 2* c0(1,3) -> 2* c0(2,2) -> 2* c0(2,4) -> 2* s0(2) -> 3* s0(4) -> 3* s0(1) -> 3* s0(3) -> 3* g0(2) -> 4* g0(4) -> 4* g0(1) -> 4* g0(3) -> 4* problem: Qed