NO (ignored inputs)COMMENT Example 17 of \cite{Aoto2013} COMMENT from the collection of \cite{Aoto2013} Rewrite Rules: [ c -> f(c,d), c -> h(c,d), f(?x,?y) -> h(g(?y),?x), h(?x,?y) -> f(g(?y),?x) ] Apply Direct Methods... Inner CPs: [ ] Outer CPs: [ f(c,d) = h(c,d) ] Overlay, check Innermost Termination... unknown Innermost Terminating unknown Knuth & Bendix Linear unknown Development Closed unknown Strongly Closed unknown Weakly-Non-Overlapping & Non-Collapsing & Shallow unknown Upside-Parallel-Closed/Outside-Closed (inner) Parallel CPs: (not computed) unknown Toyama (Parallel CPs) Simultaneous CPs: [ h(c,d) = f(c,d), f(c,d) = h(c,d) ] unknown Okui (Simultaneous CPs) unknown Strongly Depth-Preserving & Root-E-Closed/Non-E-Overlapping unknown Strongly Weight-Preserving & Root-E-Closed/Non-E-Overlapping check Locally Decreasing Diagrams by Rule Labelling... Critical Pair by Rules <1, 0> preceded by [] unknown Diagram Decreasing check Non-Confluence... obtain 14 rules by 3 steps unfolding strenghten f(c,d) and h(c,d) strenghten h(c,d) and f(c,d) strenghten f(g(d),c) and f(c,d) strenghten f(g(d),c) and h(c,d) obtain 100 candidates for checking non-joinability check by TCAP-Approximation (failure) check by Root-Approximation (failure) check by Ordering(rpo), check by Tree-Automata Approximation (success) Precedence: c : Mul []; h : Mul [1], f : Mul [2], d : Mul []; g : !1; Obtained: h(f(d)) :(gt): f(d) (c -> f(c,d): not usable) (c -> h(c,d): not usable) f(?y) :(ge): h(?y) h(?x) :(ge): f(?x) Witness for Non-Confluence: Direct Methods: not CR Final result: not CR 257.trs: Success(not CR) (1194 msec.)