I studied abroad in modern times

Tang Lingwu cherished the last sip of milk tea into her mouth, thought for a moment with the empty milk tea cup, stuffed it into her backpack, and then took Zheng Fa upstairs.

"I drank your milk tea, and this matter is all my responsibility!"

She just missed patting her bulging chest.

When she reached the fourth floor, she stopped, pointed to a security door and said, "My teacher lives here. Please wait for me to go in and talk to him."

She knocked on the security door, and the person inside opened the door. Tang Lingwu gave Zheng Fa a waiting look, slipped in through the crack in the door, and left the security door ajar.

Zheng Fa stood behind the door and waited, and the voices inside could be heard vaguely.

"Teacher Bai, can I ask you for a favor?" Tang Lingwu's voice was clear.

Zheng Fa grinned.

The sweetness of this voice is a bit off the mark.

"You tell me first."

What came was the voice of an old man, full of vigilance, and Zheng Fa felt a little familiar for some reason.

"I've brought you another student!"

"Are you in love?"

The old man's voice suddenly became louder.

"What love? I mean, I have a classmate who wants to ask you a question."

"A studious student? Male or female?" The old man obviously did not believe Tang Lingwu's words.

"Male...but we are really not in love!"

It can be heard that Tang Lingwu worked very hard for a cup of milk tea.

"Tch, I don't know what you young people are thinking. This young man is not very eager to learn. I have seen too many lustful ones! I won't agree."

The old man obviously regarded Tang Lingwu as a junior.

A certain amount of hostility towards every male around her.

"Teacher Bai, aren't you a university professor? You answer questions and answer questions. You teach without distinction!"

The old man's tone was indignant: "I'm retired! Do you understand that I'm retired? I taught students before I retired, and I still teach students after retirement. Didn't I retire in vain?"

This old man obviously resents his job.

Simply put, lazy.

"Then if you teach me one, it's still a lesson. It's not a big deal if you teach one more!"

Tang Lingwu was really working hard. Listening to this voice outside, Zheng Fa felt numb all over.

It's hard to imagine that it came from her slightly cold face.

"You are different. Your mother gave you too much... No, I mean you are very talented in mathematics! You are smart!"

"Then since you haven't seen anyone, maybe he also has a talent?"

"There is such a thing as mathematical talent. If you see a person and just say he doesn't have it, this method is actually very accurate."

"...Is this really something that can't be done?"

"Can't do it!"

…

Tang Lingwu walked out of the room with a trace of apology on her face.

"Sorry, he doesn't want to see you."

"It's okay, you've done your best."

Listening outside, Zheng Fa could imagine how Tang Lingwu acted coquettishly in front of the other party to please him, and he could even hear the other party's hard work in his voice.

What's more, the cup of milk tea was actually to thank Tang Lingwu for bringing him here.

He also heard just now that Tang Lingwu's family spent a lot of money to find this teacher for her.

A hundred times twenty-eight dollars is not enough.

I just want a cup of milk tea to make this teacher willing to teach me. He is not that greedy yet.

"How about..." Tang Lingwu turned around and looked at her backpack, which still contained an empty milk tea cup, and said hesitantly: "Shall I buy you a cup of milk tea?"

"That's not the case. If you are really embarrassed, I will ask you if I have any questions in the future. I can't ask the teacher, but it's almost the same as asking the students."

"Don't worry, I know how to do it, and I will definitely teach you!"

"What the hell! Just buying you a cup of milk tea? He just wants to take the opportunity to talk to you more!"

An old man's voice came from behind her, and he seemed to hate iron.

Zheng Fa watched helplessly as a white curly head poked out from the crack in the door.

Looking at this familiar old face.

Zheng Fa's heart suddenly dawned on him. What I said sounded familiar!

…

In the house, the three of them were sitting on the sofa in the living room, and the atmosphere was a little awkward for a while.

Zheng Fa and Teacher Bai, as well as the curly-haired old man they met in the park before, didn't know how to speak.

Tang Lingwu's face was still a little confused. She looked at this and then that, as if she didn't know why three people suddenly entered the room.

"That... young hero."

"You can just call me Xiao Zheng, or classmate Zheng."

Hearing the word "young hero", especially in front of a classmate like Tang Lingwu, Zheng Fa felt an inexplicable sense of shame.

"Okay, classmate Zheng, please call me Lao Bai or Teacher Bai." The old man continued to ask, "Is that you the person she was talking about just now?"

"Well, I came across some pictures and wanted to show them to Teacher Bai."

"No hurry, no rush, do you want to tutor with me?"

"I don't expect to be your student, Teacher Bai. Just ask two questions."

Zheng Fa recalled the man's categorical refusal just now and said embarrassedly.

"Don't! I just thought about it. I have been a teacher all my life and I retired all of a sudden. I can't stop my desire to teach and educate people."

The expression on Tang Lingwu's face was full of question marks.

Isn't that what you said just now?

Zheng Fa was also stunned and looked at the old man's sincere face.

"Teacher Bai, what do you mean..."

"What I mean is that I am a math student, so I want to find some students with good math talent to teach. Young man, no, classmate Zheng, your sect should also find some talented people to teach some secrets?"

"Hmm?"

"Look at me..." Teacher Bai pointed at himself again.

"I can see at a glance that Teacher Bai has extraordinary talent!"

Zheng Fa suddenly realized.

"I think you are also very smart in math!"

Tang Lingwu watched from the side, her eyes full of confusion.

These two men seemed to have completed a dirty deal in front of her.

...

Looking at the pictures handed over by Zheng Fa, Teacher Bai frowned slightly, and his face looked a little serious.

Compared to his playful appearance just now, he now has the style of a university professor.

He traced a few pictures with his fingers, looked up and asked Zheng Fa:

"That's all?"

"Yeah."

"Then I can't tell what it is." Teacher Bai put down a few papers: "Why don't you ask those fortune tellers to see? Let them count with their fingers and tell what this thing is."

Zheng Fa: "..."

"But if you ask me if there are any rules in these patterns, there are some."

"Tell me."

"This, this and this." Teacher Bai pointed to the three pictures and said uncertainly: "If we look at it from the perspective of our mathematical topology, it is actually a pattern."

"Ah?"

Zheng Fa looked at the three pictures in confusion.

Looking left and right, he really couldn't tell that they were the same.

"Topo... what?"

"This involves a relatively elementary and simple topological concept, called homeomorphism..." Teacher Bai talked about his professional matters, and he was eloquent and dancing with joy.

After talking for a long time, he stopped and asked Zheng Fa: "Do you understand?"

"..."

Zheng Fa felt like a pedant was trying to pry open his head with a chisel, but he seemed to have mastered the iron head skill without any guidance.