-- 1а) комбинаторы C, B, S
def C : (α → β → γ) → β → α → γ :=
  λf b a, f a (b)

def B : (α → β) → (γ → α) → γ → β :=
  λf g c, f (g c)

def S : (α → β → γ) → (α → β) → α → γ :=
  λf g a, f a (g a)

-- 1б)
def some_nonsense : (α → β → γ) → α → (α → γ) → β → γ :=
  λf a g b, f a b

-- 1в)
def more_nonsense : (γ → (α → β) → α) → γ → β → α :=
  λf c b, (f c) (λa, b)

-- 1г)
def even_more_nonsense : (α → α → β) → (β → γ) → α → β → γ :=
  λf g a b, g b