; @author Naoki Nishida
; @cops 873
(format CTRS oriented :problem infeasibility)
(fun 0 0)
(fun e 1)
(fun false 0)
(fun s 1)
(fun true 0)
(rule (e 0) true)
(rule (e (s x)) true (= (e x) false))
(rule (e (s x)) false (= (e x) true))
(infeasible? (= (e x1) false) (= (e x1) true))