16. DecimalToHexadecimal

using System;

class DecimalToHexadecimal
{
    static void Main()
    {
        long n = long.Parse(Console.ReadLine());
        string hex = "";
        do
        {
            switch (n % 16)
            {
                case 10: hex = "A" + hex; break;
                case 11: hex = "B" + hex; break;
                case 12: hex = "C" + hex; break;
                case 13: hex = "D" + hex; break;
                case 14: hex = "E" + hex; break;
                case 15: hex = "F" + hex; break;
                default: hex = n % 16 + hex; break;
            }
            n = n / 16;
        } while (n > 0);
        Console.WriteLine(hex);
    }
}