using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        HashSet<int> lowNumbers = new HashSet<int>();

        HashSet<int> highNumbers = new HashSet<int>();

​

        for (int i = 0; i < 9; i++)

        {

            lowNumbers.Add(i);

        }

​

        for (int i = 0; i < 6; i++)

        {

            highNumbers.Add(i);

        }

​

        Console.Write("lowNumbers contains {0} elements: ", lowNumbers.Count);

        DisplaySet(lowNumbers);

​

        Console.Write("highNumbers contains {0} elements: ", highNumbers.Count);

        DisplaySet(highNumbers);

​

        Console.WriteLine("lowNumbers SymmetricExceptWith highNumbers...");

        lowNumbers.SymmetricExceptWith(highNumbers);

​

        Console.Write("lowNumbers contains {0} elements: ", lowNumbers.Count);

        DisplaySet(lowNumbers);

​

    }

    static void DisplaySet(HashSet<int> set)

    {

        Console.Write("{");

        foreach (int i in set)

        {

            Console.Write(" {0}", i);

        }

        Console.WriteLine(" }");

    }

}