intro (_ : compare n m = Ordering.eq) (_ : compare k j = Ordering.eq)
ℕ : Type
inst✝⁴ : Core ℕ
inst✝³ : Induction ℕ
inst✝² : Addition ℕ
inst✝¹ : Sign ℕ
order_inst : Order ℕ
inst✝ : Compare ℕ
ord : Ordering
n m k j : ℕ
⊢ compare n m = Ordering.eq → compare k j = Ordering.eq → compare (n + k) (m + j) = Ordering.eq
ℕ : Type
inst✝⁴ : Core ℕ
inst✝³ : Induction ℕ
inst✝² : Addition ℕ
inst✝¹ : Sign ℕ
order_inst : Order ℕ
inst✝ : Compare ℕ
ord : Ordering
n m k j : ℕ
x✝¹ : compare n m = Ordering.eq
x✝ : compare k j = Ordering.eq
⊢ compare (n + k) (m + j) = Ordering.eq