(ignored inputs)COMMENT Exercise 6.5{e} of \cite{BN98}
Rewrite Rules:
   [ f(f(?x,?y),?z) -> f(?x,f(?y,?z)),
     f(1,?x) -> ?x ]
Apply Direct Methods...
Inner CPs:
   [ f(?x_1,?z) = f(1,f(?x_1,?z)),
     f(f(?x,f(?y,?z)),?z_1) = f(f(?x,?y),f(?z,?z_1)) ]
Outer CPs:
   [  ]
not Overlay, check Termination...
Terminating, WCR
Knuth&Bendix
Direct Methods: CR

Final result: CR
/local-scratch/hzankl/2012/cops2012/14.trs: Success(CR)
(7 msec.)