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: 4
  enrichment: match
  automaton:
   final states: {5}
   transitions:
    s3(10) -> 13*
    s3(13) -> 13*
    f1(9) -> 5*
    f4(18) -> 5*
    c1(8,5) -> 9*
    c1(5,8) -> 9*
    c4(17,13) -> 18*
    c4(17,10) -> 18*
    s1(10) -> 8*
    s1(5) -> 8*
    s1(13) -> 8*
    s1(8) -> 8*
    s4(17) -> 17*
    s4(13) -> 17*
    f2(11) -> 5*
    c2(10,5) -> 11*
    c2(10,13) -> 11*
    c2(10,8) -> 11*
    c2(10,10) -> 11*
    f0(5) -> 5*
    s2(10) -> 10*
    s2(5) -> 10*
    c0(5,5) -> 5*
    f3(14) -> 5*
    s0(5) -> 5*
    c3(13,5) -> 14*
    c3(13,13) -> 14*
    c3(17,5) -> 14*
    c3(13,10) -> 14*
    g0(5) -> 5*
  problem:
   
  Qed