MAYBE
Input TRS:
      1: a(b(x1)) -> b(b(b(b(x1))))
      2: b(a(x1)) -> a(a(a(a(x1))))
      3: a(x1) -> x1
      4: b(x1) -> x1
Number of strict rules: 4
Direct POLO(bPol) ... failed.
Uncurrying ... failed.
Dependency Pairs:
     #1: #b(a(x1)) -> #a(a(a(a(x1))))
     #2: #b(a(x1)) -> #a(a(a(x1)))
     #3: #b(a(x1)) -> #a(a(x1))
     #4: #a(b(x1)) -> #b(b(b(b(x1))))
     #5: #a(b(x1)) -> #b(b(b(x1)))
     #6: #a(b(x1)) -> #b(b(x1))
Number of SCCs: 1, DPs: 6
  SCC { #1..6 }
POLO(Sum)... POLO(max)... QLPOS... POLO(mSum)... QWPOpS(mSum)... Mat2b... failed.
Finding a loop...  failed.