Day1 ⇐ {
  nums ← •BQN⎊0¨ •FLines 𝕩
  sums ← ∨ (+´ {𝕩↑𝕨↓nums}´)¨ (»⋈¨ ⊢-») / 0⊸≡¨ nums
  ⟨⊑sums, +´ 3↑sums⟩
}
•Show Day1 ⊑•args