Rage_Quit(copy)

using System;
using System.Collections.Generic;
using System.Linq;

namespace Rage_Quit
{
    class Program
    {
        static void Main(string[] args)
        {
            string input = Console.ReadLine().ToUpper();

            List<char> result = new List<char>();
            List<char> currResult = new List<char>();

            for (int i = 0; i < input.Length; i++)
            {
                char ch = input[i];

                if (!char.IsNumber(ch))
                {
                    currResult.Add(ch);
                }

                if (char.IsNumber(ch))
                {
                    int count = 0;
                    if (i < input.Length - 1 && char.IsNumber(input[i + 1]))
                    {
                        string str = input.Substring(i, 2);
                        count = int.Parse(str.ToString());
                    }
                    else
                    {
                        count = int.Parse(ch.ToString());
                    }

                    if (count > 0)
                    {
                        for (int j = 0; j < count; j++)
                        {
                            result.AddRange(currResult);
                        }
                    }
                    currResult.Clear();
                }
            }
            string res = new string(result.ToArray());
            Console.WriteLine("Unique symbols used: {0}", res.Distinct().Count());
            Console.WriteLine(res);
        }
    }
}