C# fastest intersection of 2 sets of sorted numbers

Question

I\'m calculating intersection of 2 sets of sorted numbers in a time-critical part of my application. This calculation is the biggest bottleneck of the whole application so I

Answer 1

try

firstSet.InterSect (secondSet).ToList ()

or

firstSet.Join(secondSet, o => o, id => id, (o, id) => o)