(ignored inputs)COMMENT doi:10.1017/CBO9781139172752 [4] Exercise 6.5 ( e ) submitted by: Takahito Aoto , Junichi Yoshida , and Yoshihito Toyama 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 Combined result: CR 14.trs: Success(CR) YES (5 msec.)