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