using System;
using System.Text.RegularExpressions;

public class Test
{
	public static void Main()
	{
		// your code goes here
		Console.WriteLine(Modify("1,2,3,4,5,6,7,8,9"));
	}
	
	static string Modify(string value)
	{
		string sSnr = Regex.Replace(value, "\r\n", ", ");
        
        MatchCollection matches = Regex.Matches(sSnr, Regex.Escape(","));
        int anz = 0;
        int y;
        int addAnz = 0;
        foreach (Match m in matches)
        {
        	anz++;
            y = anz % 3;
            if (y == 0)
            {
                addAnz++;	
                sSnr = sSnr.Insert(m.Index + addAnz, Environment.NewLine);
            }
        }
        
        return sSnr;
	}
}