type ABC(stream:System.IO.TextReader) =
  member this.Scan1 f = stream.ReadLine() |> f
  member this.Scan2 f = stream.ReadLine().Split() |> Array.map f |> (fun a -> (a.[0], a.[1]))
  member this.Scan3 f = stream.ReadLine().Split() |> Array.map f |> (fun a -> (a.[0], a.[1], a.[2]))
  member this.Scan4 f = stream.ReadLine().Split() |> Array.map f |> (fun a -> (a.[0], a.[1], a.[2], a.[3]))
  member this.ScanVecH f = stream.ReadLine().Split() |> Array.map f
  member this.ScanVecV n f = [ for i in 1..n -> stream.ReadLine() |> f ]
  member this.ScanMatrix n f  = [ for i in 1..n do yield stream.ReadLine().Split() |> Array.map f ]
  member this.ScanCharMatrix n = [| for i in 1..n -> stream.ReadLine().ToCharArray() |]
  member this.Close () = stream.Close()

let util = ABC(stdin)

let N = util.Scan1 int

let rec countR cs =
  if (cs <> List.empty) && (List.fold (fun a -> fun c -> a + string c) "" cs |> int) > N 
  then 0
  else 
    let me = if (List.contains '3' cs) && (List.contains '5' cs) && (List.contains '7' cs)
             then 1
             else 0
    me + (countR ('3'::cs)) + (countR ('5'::cs)) + (countR ('7'::cs))

countR List.empty
|> printfn "%d"

util.Close()
