MAYBE
(ignored inputs)COMMENT doi:10.1007/978-3-319-63046-5_24 [118] Example 4 submitted by: Aart Middeldorp
input TRS:
   [ +(a,b) -> b,
     +(c,a) -> a,
     +(?x,?y) -> +(?y,?x),
     +(+(?x,?y),?z) -> +(?x,+(?y,?z)) ]
TRS:
   [ +(a,b) -> b,
     +(c,a) -> a,
     +(?x,?y) -> +(?y,?x),
     +(+(?x,?y),?z) -> +(?x,+(?y,?z)) ]
unknown UNC Completion (Strongly Closed)
problems/541.trs: Failure(unknown UNC)
(48 msec.)