using System;

​

public class Program

{

    public static void Main()

    {

        long io195=5775228828748546048;

        long io196=5764908064198375734;

​

        Console.WriteLine("Brut   " + GetNumeroCarte(io195,io196));

        Console.WriteLine("Pad    " + GetNumeroCarte(io195,io196).PadLeft(16,'0')); // Pad pour s'assurer qu'il y a bien 16 caractères

        Console.WriteLine("Futur  " + GetNumeroCarte(io195,io196).PadLeft(16,'0')[..14]); // suite à votre discussion

    }

    private static string GetNumeroCarte(long part1, long part2){

        return (hexToASCII(decToHex(part1)) + hexToASCII(decToHex(part2))).ToString();

    }

    private static string decToHex(long valeur) =>  string.Format("{0:X}", valeur);

   private static String hexToASCII(string hex)

   {

            string ascii = "";

            for (int i = 0; i < hex.Length; i += 2)

            {

​

                string part = hex.Substring(i, 2);

                char ch = (char)Convert.ToInt32(part, 16); ;

                ascii = ascii + ch;

            }

            return ascii;

        }

}