MAYBE
(ignored inputs)COMMENT TPDB SRS_Standard/Zantema_04/z108
input TRS:
   [ a(a(?x)) -> b(c(?x)),
     b(b(?x)) -> c(d(?x)),
     c(c(?x)) -> d(d(d(?x))),
     d(d(d(?x))) -> a(c(?x)) ]
TRS:
   [ a(a(?x)) -> b(c(?x)),
     b(b(?x)) -> c(d(?x)),
     c(c(?x)) -> d(d(d(?x))),
     d(d(d(?x))) -> a(c(?x)) ]
New rules by rule reversing:
   [ a(a(?x)) -> b(c(?x)),
     b(b(?x)) -> c(d(?x)),
     c(c(?x)) -> c(c(?x)),
     d(d(d(?x))) -> c(c(?x)),
     d(d(d(?x))) -> a(c(?x)) ]
problems/943.trs: Failure(unknown UNC)
(4 msec.)