public static void Main() { var set = new Set<int>(); for (int i = 1; i < 11; i++) { for (int j = 0; j < 3; j++) { set.Add(i); } } Console.WriteLine(set); Console.WriteLine(set.Count); var otherSet = new Set<int>(); for (int i = 5; i < 16; i++) { otherSet.Add(i); } Console.WriteLine(otherSet); Console.WriteLine(otherSet.Count); Console.WriteLine(set.IntersectsWith(otherSet)); Console.WriteLine(set.Union(otherSet)); }