fun countHappyDay (month, days) =
    let
        fun isHappyDay d =
            month = (d mod 10) + (d div 10)
        fun loop d =
            if days < d then 0
            else if isHappyDay d then 1 + loop (d + 1)
            else loop (d + 1)
    in
        loop 1
    end


val () =
    let
        val ans = foldl (fn ((m, d), acc) => countHappyDay (m, d) + acc)
                        0
                        [(1, 31), (2, 28), (3, 31), (4, 30), (5, 31), (6, 30),
                         (7, 31), (8, 31), (9, 30), (10, 31), (11, 30), (12, 31)]
    in
        print (Int.toString ans)
    end