MAYBE
Input TRS:
      1: a(l(x1)) -> l(a(x1))
      2: r(a(x1)) -> a(r(x1))
      3: b(l(x1)) -> b(a(r(x1)))
      4: r(b(x1)) -> l(b(x1))
Number of strict rules: 4
Direct POLO(bPol) ... failed.
Uncurrying ... failed.
Dependency Pairs:
     #1: #r(a(x1)) -> #a(r(x1))
     #2: #r(a(x1)) -> #r(x1)
     #3: #b(l(x1)) -> #b(a(r(x1)))
     #4: #b(l(x1)) -> #a(r(x1))
     #5: #b(l(x1)) -> #r(x1)
     #6: #a(l(x1)) -> #a(x1)
Number of SCCs: 3, DPs: 3
  SCC { #2 }
POLO(Sum)... succeeded.
      a 	w: x1 + 1
      b 	w: 0
      r 	w: 0
      l 	w: 0
      #r 	w: x1
      #a 	w: 0
      #b 	w: 0
    USABLE RULES: { }
    Removed DPs: #2
Number of SCCs: 2, DPs: 2
  SCC { #6 }
POLO(Sum)... succeeded.
      a 	w: 1
      b 	w: 0
      r 	w: 0
      l 	w: x1 + 1
      #r 	w: 0
      #a 	w: x1
      #b 	w: 0
    USABLE RULES: { }
    Removed DPs: #6
Number of SCCs: 1, DPs: 1
  SCC { #3 }
POLO(Sum)... POLO(max)... QLPOS... POLO(mSum)... QWPOpS(mSum)... Mat2b... failed.
Finding a loop...  failed.