MAYBE
Input TRS:
      1: f(f(x)) -> x
      2: f(x) ->= g(f(g(f(x))))
Number of strict rules: 1
Direct POLO(bPol) ... failed.
Uncurrying ... failed.
Dependency Pairs:
     #1: #f(x) ->? #f(g(f(x)))
     #2: #f(x) ->? #f(x)
Number of SCCs: 1, DPs: 2
  SCC { #1 #2 }
POLO(Sum)... POLO(max)... QLPOS... POLO(mSum)... QWPOpS(mSum)... Mat2b... failed.
Finding a loop...  failed.