fun readInt () =
    valOf (TextIO.scanStream (Int.scan StringCvt.DEC) TextIO.stdIn)


fun findAns cs =
    let
        val totalNumberOfVotes = List.foldl (fn (c, acc) => c + acc) 0 cs
        val ans = List.foldl (fn (c, acc) =>
                                 if totalNumberOfVotes div 10 < c then acc
                                 else 30 + acc)
                             0
                             cs
    in
        ans
    end


val () =
    let
        val n = readInt ()
        val cs = List.tabulate (n, fn _ => readInt ())
                        
        val ans = findAns cs
    in
        print (Int.toString ans ^ "\n")
    end