Theorem: Digraph.Walk.getVert_zero (GraphProjects/DigraphConnectivity.lean)

State before:
V : Type u
V' : Type v
V'' : Type w
G : Digraph V
G' : Digraph V'
G'' : Digraph V''
u v : V
w : Walk G u v
⊢ getVert w 0 = u
Tactic:
cases w <;> rfl
State after:
no goals