fact: Fixpoint gtr_match2 r := match r with | GtrNil => false | GtrCons (Bpush0 _) (CtreeNode _ (CtreeLeaf _) _) _ => true | GtrCons (Bpush1 _) (CtreeNode _ _ (CtreeLeaf _)) _ => true | GtrCons _ _ r' => gtr_match2 r' end.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq) fourcolor(color ctree chromogram gtree)