Theorem: SimpleGraph.neighborSet_top (ExponentialRamsey/Prereq/Mathlib/Combinatorics/SimpleGraph/Basic.lean)

State before:
V : Type u_1
V' : Type u_2
G : SimpleGraph V
K : Type u_3
K' : Type u_4
x : V
⊢ neighborSet ⊤ x = {x}ᶜ
Tactic:
ext y
State after:
case h
V : Type u_1
V' : Type u_2
G : SimpleGraph V
K : Type u_3
K' : Type u_4
x y : V
⊢ y ∈ neighborSet ⊤ x ↔ y ∈ {x}ᶜ

State before:
case h
V : Type u_1
V' : Type u_2
G : SimpleGraph V
K : Type u_3
K' : Type u_4
x y : V
⊢ y ∈ neighborSet ⊤ x ↔ y ∈ {x}ᶜ
Tactic:
rw [mem_neighborSet, top_adj, Set.mem_compl_singleton_iff, ne_comm]
State after:
no goals