
Module Module1

    Sub main()

        Dim user1 = Console.ReadLine()
        Dim dogNum As Double = CDbl(user1)
        Dim result As String = ""
        Dim names As New List(Of Char)


        ' 26進数除算
        Do
            Dim nowTag = ((dogNum - 1) Mod 26)
            Dim chrTag = Chr(Asc("a") + nowTag)
            names.Add(chrTag)
            dogNum = Math.Floor((dogNum - 1) / 26)
        Loop While dogNum > 0
        names.Reverse()

        Console.WriteLine(String.Join("", names.ToArray))
    End Sub
  end module