(*
Error: This expression has type
         Graph.Pack.Digraph.V.label -> Graph.Pack.Digraph.V.t
       but an expression was expected of type int
*)

let fun_general () =
  let ga = read_graph "blog.txt" in
  let g = fst ga in
  let b = snd ga in
  let empty = ref false in
  let first_el = ref 0 in
  while not !empty do
    let res = composanteFC ga b.(!first_el) in
    Queue.iter
      (fun x ->
        b.(x)<- (V.create -1)) res; (* this line has the error *)
    empty:=true;
    let continue = ref true in
    let i = ref 0 in
    while (( !i < (Array.length b)) && !continue ) do
      if ((V.label b.(!i))>0) then
        begin
          empty := false;
          continue := false;
          first_el := !i;
        end;
    done;
  done;
;;