no goals
V : Type u
G : SimpleGraph V
M✝ M : Subgraph G
inst✝ : (v : V) → Fintype ↑(neighborSet M v)
⊢ IsMatching M ↔ ∀ (v : V), v ∈ M.verts → degree M v = 1
simp only [degree_eq_one_iff_unique_adj, IsMatching]