how to add contacts supper fast in telegram with c#?

Jan 4 2017 5:15 AM

I have 200000 contacts(phone number) in the notepad. in fact, I wanna read numbers from notepad then add they very fast in the telegram, for example, I wanna add 20000 phone number about five minutes.I wanna do it with "winform" but I don't know how can I add super fast numbers in the telegram. in generally, is it possible?

this is telegram API