using System;

using System.Text.RegularExpressions;

public class Program

{

    public static void Main()

    {

        string text = "street1, street2, , Bengaluru, India";

        text = Regex.Replace(text, " ,+", ",").Trim(',');

        text = Regex.Replace(text, ",+", ",").Trim(',');

        Console.WriteLine(text);

    }

}