ContainsDuplicates C#

Program.cs

using System.Diagnostics;

List<int> numbers = new() { 1,2,3,4,3,5};

if (ContainsDuplicates(numbers))
{
    Console.WriteLine("Contains Duplicate? Yes");
}
else
{
    Console.WriteLine("Contains Duplicate? No");
}

static bool ContainsDuplicates<T>(IEnumerable<T> enumerable)
{
    HashSet<T> knownElements = new();

    foreach (var element in enumerable)
    {
        if (!knownElements.Add(element))
        {
            return true;
        }
    }

    return false;
}