Union of two HashSet in C#

Let us see an example to get the Union of two HashSet

Example

 Live Demo

using System; using System.Collections.Generic; public class Demo {    public static void Main(){       HashSet<int> set1 = new HashSet<int>();       set1.Add(100);       set1.Add(200);       set1.Add(300);       set1.Add(400);       set1.Add(500);       set1.Add(600);       Console.WriteLine("HashSet1 elements...");       foreach(int ele in set1){          Console.WriteLine(ele);       }       HashSet<int> set2 = new HashSet<int>();       set2.Add(100);       set2.Add(200);       set2.Add(300);       set2.Add(400);       set2.Add(500);       set2.Add(600);       Console.WriteLine("HashSet2 elements...");       foreach(int ele in set2){          Console.WriteLine(ele);       }       Console.WriteLine("Union...");       set1.UnionWith(set2);       foreach(int ele in set1){          Console.WriteLine(ele);       }    } }

Output

This will produce the following output −

HashSet1 elements... 100 200 300 400 500 600 HashSet2 elements... 100 200 300 400 500 600 Union... 100 200 300 400 500 600

Example

Let us now see another example −

 Live Demo

using System; using System.Collections.Generic; public class Demo {    public static void Main(){       HashSet<int> set1 = new HashSet<int>();       set1.Add(100);       set1.Add(200);       set1.Add(300);       set1.Add(400);       set1.Add(500);       set1.Add(600);       Console.WriteLine("HashSet1 elements...");       foreach(int ele in set1){          Console.WriteLine(ele);       }       HashSet<int> set2 = new HashSet<int>();       set2.Add(100);       set2.Add(250);       set2.Add(300);       Console.WriteLine("HashSet2 elements...");       foreach(int ele in set2){          Console.WriteLine(ele);       }       Console.WriteLine("Union...");       set1.UnionWith(set2);       foreach(int ele in set1){          Console.WriteLine(ele);       }    } }

Output

This will produce the following output −

HashSet1 elements... 100 200 300 400 500 600 HashSet2 elements... 100 250 300 Union... 100 200 300 400 500 600 250