; @author Sarah Winkler
; @cops 1137
; secret problem 2019
; category: INF
(format CTRS semi-equational :problem infeasibility)
(fun a 0)
(fun f 2)
(fun unit 0)
(rule (f x x) unit (= x a))
(rule (f x unit) x)
(rule (f (f x y) z) (f x (f y z)))
(infeasible? (= a (f a a)))