(ignored inputs)COMMENT Exercise 6.5{b} of \cite{BN98}
Rewrite Rules:
   [ +(0,?y) -> ?y,
     +(s(?x),?y) -> s(+(?x,?y)),
     +(?x,0) -> ?x,
     +(?x,s(?y)) -> s(+(?x,?y)) ]
Apply Direct Methods...
Inner CPs:
   [  ]
Outer CPs:
   [ 0 = 0,
     s(?y_3) = s(+(0,?y_3)),
     s(+(?x_1,0)) = s(?x_1),
     s(+(?x_1,s(?y_3))) = s(+(s(?x_1),?y_3)) ]
Overlay, check Innermost Termination...
Innermost Terminating (hence Terminating), WCR
Knuth&Bendix
Direct Methods: CR

Final result: CR
/local-scratch/hzankl/2012/cops2012/11.trs: Success(CR)
(12 msec.)