fix the dijkstra example wrt an API change in sasa

expe/dijkstra-ring/config.ml

@@ -10,6 +10,7 @@ let (legitimate: t Algo.legitimate_fun) =
   (* only one node is enabled *)
   let incr_token i pid =
     let s, nl = get pid in
+    let nl = List.map fst nl in
     let have_token = (if s.root then Root.enable_f s nl else P.enable_f s nl) <> [] in
     let ni = if have_token then i+1 else i in
     ni