MAYBE

'epo* (timeout of 60.0 seconds)'
--------------------------------
Answer:           MAYBE
Input Problem:    innermost runtime-complexity with respect to
  Rules:
    {  f(x, a(b(y))) -> f(a(b(x)), y)
     , f(x, b(c(y))) -> f(b(c(x)), y)
     , f(x, c(a(y))) -> f(c(a(x)), y)
     , f(a(x), y) -> f(x, a(y))
     , f(b(x), y) -> f(x, b(y))
     , f(c(x), y) -> f(x, c(y))}

Proof Output:    
  The input cannot be shown compatible