Input TRS:
    1: f(el(x),y) -> f(x,el(y))
   e1: f(x,y) ->= f(l(x),y)	[relative]
   e2: f(x,y) ->= f(x,r(y))	[relative]
   e3: l(el(x)) ->= el(l(x))	[relative]
   e4: el(r(x)) ->= r(el(x))	[relative]
Dependency Pairs:
   #1: # f(x,y) -> # f(x,r(y))	[relative]
   #2: # f(x,y) -> # f(l(x),y)	[relative]
   #3: # f(el(x),y) -> # f(x,el(y))
Number of SCCs: 1
  SCC { #1..3 }
    POLO(Sum)... removes: #3
	I(r) = 0
	I(l) = max(x1, 0)
	I(el) = max(x1 + 1, 0)
	I(# f) = max(x1 + 1, 0)
    USABLE RULES: { }
Number of SCCs: 1
  SCC { #1 #2 }
    POLO(Sum)... QLPOS... QWPOpS(mSum)... Mat2b... failed.