MAYBE
* Step 1: Failure MAYBE
  + Considered Problem:
      - Strict TRS:
          active(f(X)) -> f(active(X))
          active(f(f(a()))) -> mark(c(f(g(f(a())))))
          active(g(X)) -> g(active(X))
          c(ok(X)) -> ok(c(X))
          f(mark(X)) -> mark(f(X))
          f(ok(X)) -> ok(f(X))
          g(mark(X)) -> mark(g(X))
          g(ok(X)) -> ok(g(X))
          proper(a()) -> ok(a())
          proper(c(X)) -> c(proper(X))
          proper(f(X)) -> f(proper(X))
          proper(g(X)) -> g(proper(X))
          top(mark(X)) -> top(proper(X))
          top(ok(X)) -> top(active(X))
      - Signature:
          {active/1,c/1,f/1,g/1,proper/1,top/1} / {a/0,mark/1,ok/1}
      - Obligation:
          innermost runtime complexity wrt. defined symbols {active,c,f,g,proper,top} and constructors {a,mark,ok}
  + Applied Processor:
      NaturalPI {shape = Mixed 3, restrict = NoRestrict, uargs = UArgs, urules = URules, selector = Nothing}
  + Details:
      Incompatible
MAYBE