Exercise03DecimalToHexadecimal

/*Write a program to convert decimal numbers to their hexadecimal representation.*/

using System;
using System.Collections;
using System.Text;

public class Exercise03DecimalToHexadecimal
{
    private static void Main()
    {
        char[] hexSymbols = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
        Stack temp = new Stack();
        StringBuilder hex = new StringBuilder();
        int num = int.Parse(Console.ReadLine());
        byte sign = 0;
        byte mod = 0;
        int index = 0;
        if (num < 0)
        {
            sign = 15;
            num *= -1;
            mod = 1;
        }

        while (num != 0)
        {
            index = sign - (num % 16) + mod;
            if (index == 16)
            {
                index = 0;
                mod = 1;
            }
            else
            {
                mod = 0;
            }

            temp.Push(hexSymbols[Math.Abs(index)]);
            num = num / 16;
        }

        hex.Append(hexSymbols[sign]);
        for (int i = 0; i < 8 - temp.Count; i++)
        {
            hex.Append(hexSymbols[sign]);
        }

        foreach (var item in temp)
        {
            hex.Append(item);
        }

        Console.WriteLine("0x" + hex + "\n\n");
    }
}