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

exception WrongMonth
fun intToMonth 1 = Date.Jan
  | intToMonth 2 = Date.Feb
  | intToMonth 3 = Date.Mar
  | intToMonth 4 = Date.Apr
  | intToMonth 5 = Date.May
  | intToMonth 6 = Date.Jun
  | intToMonth 7 = Date.Jul
  | intToMonth 8 = Date.Aug
  | intToMonth 9 = Date.Sep
  | intToMonth 10 = Date.Oct
  | intToMonth 11 = Date.Nov
  | intToMonth 12 = Date.Dec
  | intToMonth _ = raise WrongMonth

fun readDate () =
    let
        val y = readInt ()
        val _ = TextIO.scanStream Char.scan TextIO.stdIn (* skip #"/" *)
        val m = readInt ()
        val _ = TextIO.scanStream Char.scan TextIO.stdIn (* skip #"/" *)
        val d = readInt ()
    in
        (y, m, d)
    end


val () =
    let
        val (y, m, d) = readDate ()
        val ans = Date.date {year = y, month = intToMonth m, day = d + 2, hour = 0, minute = 0, second = 0, offset = SOME(Time.zeroTime)}
    in
        print ((Date.fmt "%Y/%m/%d" ans) ^ "\n")  
    end