val graph : ?loops:bool -> v:int -> e:int -> unit -> graph
val labeled : (vertex -> vertex -> edge_label) -> ?loops:bool -> v:int -> e:int -> unit -> graph
val random_few_edges : loops:bool -> v:int -> e:int -> graph
val random_many_edges : loops:bool -> v:int -> e:int -> graph
val gnp : ?loops:bool -> v:int -> prob:float -> unit -> graph
val gnp_labeled : (vertex -> vertex -> edge_label) -> ?loops:bool -> v:int -> prob:float -> unit -> graph