The love of functions and derivatives

Derivative originally arranged for Derivative to be picked up and discharged from the hospital tonight, but suddenly received a text message at six o'clock——

"Let's chat in private room A06 of a restaurant at 30:11 tonight. I'm a delivery guy."

Derivative's expression was quite calm. He had expected that the delivery boy would come back, but he didn't expect that the delivery boy would contact him and expressed his desire to have a talk with him.Derivative made a call immediately, but was hung up by the other party, and after 1 minute——

#You received a text message from 12345678901#

"Don't call me, you can send a text message. Don't even think about calling the police, you know the police can't catch me. Also, if you break the contract, be late, or disclose the news of your appointment to others tonight, then I don't mind letting you The function is injured again."

The derivative had no choice but to reply with the word "good".

In order to keep the appointment on time and leave 10 minutes early, Derivative called Function on the way to apologize.After arriving at the restaurant, after the private room designated by Derivative, Derivative pushed open the door and saw the takeaway boy sitting on the seat with a weird smile.

Derivative closed the door and sat opposite to the delivery guy.

"Hello, Derivative." The takeaway boy extended his right hand to Derivative.

Derivative directly ignored the takeaway brother's handshake idea, hung the takeaway boy's hand in the air, and asked straight to the point: "What do you want me to do?"

"Oh, don't be nervous. I just want to ask you something." The takeaway boy said in a relaxed tone, with a foolish look, "Since everyone is going to be honest with each other, why don't you guess, who am I?"

Derivative looked at the delivery boy coldly: "Today is the second time I see you. The first time was at Function's house. I don't know you."

"Then let me give you a hint." The takeaway boy was holding the black tea, and the spoon in his hand was circling in the tea. Because it touched the wall of the cup, the ceramic and the iron spoon collided and made a crisp sound, "I have Mr. He's Diary. I know all the stories about you and He Jun."

Derivative lost his composure for a moment, and he calmed down: "So what?"

"Blame me." The delivery boy sighed with some self-mocking, "I didn't read the diary before the first assassination of the function. If I had finished reading it, I wouldn't have such a stupid idea that I had already succeeded."

"Hey, let me give you another hint." The delivery boy looked at his reflection in the tea, "Actually, if you look at my face, you should be able to understand the relationship between me and He Jun."

The takeaway boy raised his head and turned his face to the derivative. After capturing the slight change in the expression of the derivative, the delivery boy smiled: "Have you already guessed it?"

"You are the son of a madman."

Derivative's gaze shifted from the school badge on the delivery boy's left chest to the delivery boy's eyes. He stared at the delivery boy and said word by word, "I'm also a senior in a high school."