proposition: Lemma cmp_linear: forall a b, cmp_rel a b \/ cmp_rel b a.
proof: Proof. intros [? ?] [? ?]. unfold cmp_rel, cmp; simpl. case_eq (Int.lt i i0); auto. intro. right. case_eq (Int.lt i0 i); auto. intro. exfalso. apply lt_inv in H. apply lt_inv in H0. lia. Qed.
imports: VST.floyd.proofauto Coq.ZArith.ZArith CertiGraph.floyd_ext.closed_lemmas CertiGraph.kruskal.kruskal_edgelist RelationClasses CertiGraph.binheap.binary_heap_model CertiGraph.binheap.binary_heap_Zmodel