How do I implement a HashSet in C#?

How do I implement a HashSet in C#?

To implement a HashSet in C#, you can use the HashSet<T> class from the System.Collections.Generic namespace. Here's a simple example:

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        HashSet<int> numbers = new HashSet<int>();
        numbers.Add(1);
        numbers.Add(2);
        numbers.Add(3);

        foreach (var number in numbers)
        {
            Console.WriteLine(number);
        }
    }
}

What are the benefits of using a HashSet over a List?

HashSets provide faster lookups, as they use a hash table for storage, making operations like add, remove, and contains average O(1) time complexity. Lists, on the other hand, have O(n) time complexity for these operations.

Can I store custom objects in a HashSet?

Yes, you can store custom objects in a HashSet. However, you need to override the Equals and GetHashCode methods in your class to ensure proper behavior when checking for duplicates.

How do I remove an item from a HashSet?

You can remove an item from a HashSet using the Remove method. For example:

numbers.Remove(2);

This will remove the number 2 from the HashSet if it exists.