; @author Raul Gutierrez
; @author Salvador Lucas
; @doi 10.4230/LIPIcs.FSCD.2016.29
; @cops 936
; [90] Example 3
(format CTRS oriented :problem infeasibility)
(fun a 0)
(fun b 0)
(fun f 1)
(rule (f x) a (= x a))
(rule (f x) b (= x b))
(infeasible? (= x a) (= x b))