using System;
using System.Linq;
using System.Text.RegularExpressions;
 
public class Test
{
	public static void Main()
	{
		Console.WriteLine(Compress("aaaabbbcccddasdfasdf"));
		Console.WriteLine(Compress("aaabbccdddeezbbb"));
	}
 
    public static string Compress(string str)
    {
        return Regex.Matches(str, @"(.)\1{0,}")
                    .Cast<Match>()
                    .Select(x =>
                        "" + x.Value[0] +
                        ((x.Length == 1) ? String.Empty : x.Length.ToString()))
                    .Aggregate((a, b) => a + b);
    }
}

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