
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 Mod 26)
            If 0 = nowTag Then nowTag = 26
            Dim chrTag = Chr(Asc("a") + nowTag - 1)
            names.Add(chrTag)
            If 27 <= dogNum Then
                dogNum = Math.Floor(dogNum / 26)
            Else
                dogNum = 0
            End If
        Loop While dogNum > 0
        names.Reverse()

        Console.WriteLine(String.Join("", names.ToArray))

    End Sub
end module