using System;
using System.Text;
class DecToHex
{
static void Main(string[] args)
{
long num = 100000;
Console.WriteLine(DecimalToHex(num)); // 186A0
}
private static string DecimalToHex(long num)
{
var res = new StringBuilder();
while (num > 0)
{
var reminder = num % 16;
if (reminder > 9)
{
res.Insert(0, (char)(reminder + 55));
}
else
{
res.Insert(0, reminder);
}
num /= 16;
}
return res.ToString();
}
}