Count the number of fingers of leap motion in Unity5?

I am practicing Unity with using Leap Motion in these days.
I was wondering how I can count the fingers, recognized by Leap Motion.

@archandy85
https://developer-archive.leapmotion.com/documentation/csharp/api/Leap.Finger.html
Please read Finger.IsExtended,Finger — Leap Motion C# SDK v3.2 documentation

Please read Bool Fimger.IsExtended