MAYBE
* Step 1: Failure MAYBE
  + Considered Problem:
      - Strict TRS:
          eq(0(),0()) -> true()
          eq(0(),s(X)) -> false()
          eq(s(X),0()) -> false()
          eq(s(X),s(Y)) -> eq(X,Y)
          ifrm(false(),N,add(M,X)) -> add(M,rm(N,X))
          ifrm(true(),N,add(M,X)) -> rm(N,X)
          purge(add(N,X)) -> add(N,purge(rm(N,X)))
          purge(nil()) -> nil()
          rm(N,add(M,X)) -> ifrm(eq(N,M),N,add(M,X))
          rm(N,nil()) -> nil()
      - Signature:
          {eq/2,ifrm/3,purge/1,rm/2} / {0/0,add/2,false/0,nil/0,s/1,true/0}
      - Obligation:
          innermost runtime complexity wrt. defined symbols {eq,ifrm,purge,rm} and constructors {0,add,false,nil,s
          ,true}
  + Applied Processor:
      NaturalPI {shape = Mixed 3, restrict = NoRestrict, uargs = UArgs, urules = URules, selector = Nothing}
  + Details:
      Incompatible
MAYBE