new B ∧ F → (F ∨ G → (E ∧ D → (B ∧ A → ((F → B ∧ H) → (F ∧ A → D ∧ D)))))
intro
cases 0
intro
intro
cases 4
intro
cases 7
intro
intro
cases 11
cases 0
cases 4
cases 7
cases 11
constructor
exact 6
exact 6