[Serializable]
	public class EmailException : Exception
	{
		public EmailException() : base(){}
		public EmailException(string message):base(message){}
		public EmailException(string message, Exception in):base(message,in){}
	}

		public SplitDataSet():this(null,null)
		{
		}

		public SplitDataSet(DataTable mainDt, DataSet childDataSet)
		{
			mainDataTable = mainDt;
			childTables = childDataSet;
		}

class a
{
    a():base(){}
    a(string b):this(){}
    a(int a): this("hello") {}
}