revert bs
α : Type u
r : α → α → Prop
as bs : List α
⊢ relHead r as bs → Ascending (flip r) as → Ascending r bs → Ascending r (List.reverseAux as bs)
α : Type u
r : α → α → Prop
as : List α
⊢ ∀ {bs : List α}, relHead r as bs → Ascending (flip r) as → Ascending r bs → Ascending r (List.reverseAux as bs)