Java Treemap Equivalent in C#?

Does SortedDictionary class help?

Another great implementation of a Red Black Tree in .NET can be found here:

I don't think C# has one natively. However there are plenty of examples of Red-Black implementations out there. Here is one:-

Generally use the sorted set

public class ItemComparer : IComparer<int[]>
{
    public int Compare(int[] item1, int[] item2)
    {
        if (item1[0] != item2[0]) return item1[0].CompareTo(item2[0]);
        return item1[1].CompareTo(item2[1]);
    }
}
var s = new SortedSet<int[]>(new ItemComparer());