Theorem: Digraph.Walk.map_fst_darts (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
p : Walk G u v
⊢ List.map (fun x => x.fst) (edges p) = List.dropLast (support p)
Tactic:
simpa! using congr_arg List.dropLast (map_fst_edges_append p)
State after:
no goals