Fastest way to search a number in a list of ranges

Question

I have the following code to find a match for a number in a list of ranges.

public class RangeGroup
{
    public uint RangeGroupId { get; set; }
    public u         


        

Answer 1

If you populate the list only once you can do a magic trick:

• Sort the List
• Use BinarySearch

Sort takes O(Nlog(N)) time and is only done once. Binary search takes O(log(N)), which takes at most 17 comparisons for 100.000 items.