using System;

public class Program

{   

    public static void Main()

    {       

        GetExcel("" , 26  * 3 + 1);

    }

    public static void GetExcel(string suffix, int n)

    {       

        if(n <= 26)

        {

            Console.WriteLine(((char)((int)('A') - 1 + n)).ToString() + suffix);

            return;

        }

        var r = n % 26;

        char c;

        if(r == 0)

        {

            c = (char)(int)('Z');

            suffix = c.ToString() + suffix;

            n = n - 26;

            GetExcel(suffix, n / 26);

        }

        else

        {

            c = (char)((int)('A') - 1 + r);     

            suffix = c.ToString() + suffix;

            GetExcel(suffix, n / 26);

        }

    }

}