fun readStr () =
    let
        fun scan reader stream = SOME (StringCvt.splitl (not o Char.isSpace) reader (StringCvt.skipWS reader stream))
    in
        valOf (TextIO.scanStream scan TextIO.stdIn)
    end


val () =
    let
        val t = readStr ()
        val fields = String.fields (fn ch => ch = #"(" orelse ch = #")") t
        val ans = List.hd fields ^ "@" ^ (List.last fields)
    in
        print (ans ^ "\n")
    end