Reborn in 1977, I will no longer be my brother's blood bag.

The next day at noon, in the Automation Building, Lin Xiuhe arrived on time with the documents.

Compared to the bustling teaching building, this place is much quieter.

Various experimental drawings and technical documents were hung on both sides of the corridor. She couldn't understand much of it yet, but just looking at them, she could feel a strong sense of professionalism.

She quickly found the classroom using the information provided.

Before the door was even opened, there were already seven or eight people standing outside, men and women, all quite young, but each of them carried a similar air about them—confidence, even pride.

Because almost everyone who can be here is one of the best students from their respective provinces.

Some people are discussing math problems, some are arguing about a certain formula, and others are looking down at English materials.

An invisible sense of competition permeated the air.

As soon as Lin Xiuhe approached, several pairs of eyes fell on her.

"Is she Lin Xiuhe?" someone asked in a low voice.

"It should be."

"The one who got first place in the placement test."

"From the countryside?"

The voice wasn't loud, but there was no deliberate attempt to avoid her.

Lin Xiuhe remained calm and found a corner to stand in.

She had experienced too many gazes in her past life, so these were nothing to her.

Just then, a voice came from behind: "You're here pretty early."

Lin Xiuhe turned around.

Li Mingyuan.

The other person was holding an original English textbook, and remained calm.

"You're not too late either."

Li Mingyuan smiled but didn't say anything more.

However, the people around them became noticeably quieter, because everyone knew that the first and second place winners of the preliminary test had both arrived.

Shortly afterward, the classroom door opened, and everyone entered one after another.

It wasn't a large room, with only a dozen or so tables. It was clearly not a regular classroom; it was more like an internal discussion meeting.

As soon as Lin Xiuhe sat down, she overheard two boys next to her chatting: "I heard that Professor Chen only selects a few people each year."

"Really?"

"Seriously, even the top provincial scorer from last year didn't get in."

"That strict?"

"Nonsense." The two lowered their voices, but many people still heard them, making the atmosphere even more tense.

Just then, Professor Chen walked in.

The classroom fell silent instantly.

The old man placed the documents on the podium, glanced around at the crowd, and without any pleasantries or small talk, went straight to the point: "Do you know why you're here?"

No one answered.

Professor Chen continued, "Because of grades, but grades do not represent ability."

With just one sentence, everyone's expression changed.

The old man slowly stepped down from the podium, his gaze sweeping across the faces of the students: "The college entrance exam tests the past; what I want to see today is the future."

The air quieted down, and even breathing became softer.

Professor Chen picked up the chalk and wrote a problem on the blackboard with strong, vigorous handwriting.

Soon, the entire blackboard was filled with writing.

Many people in the classroom began to change their expressions—because this was not a classroom question at all, and it even exceeded the content they had mastered at this stage.

Li Mingyuan frowned slightly. A girl next to him was already working on calculations, and others were starting to look through documents.

Lin Xiuhe slowly sat up straight, because she actually remembered this question.

After starting her career in her previous life, she came across similar control models. Although they were not exactly the same, the core ideas were very similar.

On the podium, Professor Chen put down the chalk: "Half an hour. Whoever can come up with a solution can stay."

After he finished speaking, the classroom fell completely silent.

Everyone began to hunch over their work, the sound of papers turning constantly filling the air.

Time passed slowly—ten minutes, fifteen minutes, twenty minutes.

Some people put down their pens, some frowned more and more, and some simply started to space out, because they couldn't find any direction at all.

Li Mingyuan filled two pages, but still felt something was wrong, and beads of sweat appeared on his forehead.

The atmosphere in the classroom grew increasingly oppressive.

Just then, a voice suddenly rang out: "Teacher."

The air suddenly went still, and everyone looked up at the same time—the speaker was Lin Xiuhe.

A hint of surprise flashed in Professor Chen's eyes: "You have an idea?"

It's not a complete answer, but it's worth a try.

Many people in the classroom frowned immediately, and even Li Mingyuan looked up—he had spent twenty minutes trying to find his way, and Lin Xiuhe had already raised her hand?

Professor Chen didn't say anything, he just nodded: "Come up."

Lin Xiuhe stood up, picked up the chalk, and walked to the blackboard.

The classroom was so quiet you could hear a pin drop, and all eyes were on her—some were suspicious, some were curious, and some were waiting to see her make a fool of herself.

After all, this is Tsinghua University, and no one thinks they are inferior to others.

Lin Xiuhe looked at the blackboard, took a deep breath, and then wrote down the first line of formulas, the second line, and the third line.

As she continued her deductions, the person who had been frowning began to slowly raise their head—

Because her approach is completely different from everyone else's; instead of working backward from the result, she directly approaches the system logic, which is simple yet effective.

Li Mingyuan stopped writing, and for the first time, his gaze became truly serious, because he suddenly realized that he had just gone in the wrong direction.

Meanwhile, Professor Chen's gaze gradually changed beside the podium—from calm to serious, and then to surprise.

Time passed slowly, and finally Lin Xiuhe put down the chalk.

The classroom was eerily quiet; no one spoke—because many people simply hadn't considered that the answer could be solved in this way.

A few seconds later, Professor Chen slowly spoke: "Does anyone have another idea?"

No one answered; the entire classroom was silent.

The old man stared at the blackboard in silence for a long time before turning to the crowd: "Remember, this question isn't to test you, but to tell you something—"

"There are no top scorers in the college entrance examination here, nor are there any first-place finishers in the preliminary examination. From the moment you step into Tsinghua University, everyone has to line up again."

The classroom fell silent, but many already understood that while the statement was addressed to everyone, it was actually telling them as well—

The girl in front of me from the Red Flag Commune is not just lucky; she deserves to stand here.

As soon as Lin Xiuhe returned to her seat, she felt a gaze fall upon her.

She turned her head and saw Li Mingyuan looking at her. After a long while, he suddenly smiled and said, "It seems that the document I sent yesterday was a bit unnecessary."

Li Mingyuan admitted for the first time—

He underestimated Lin Xiuhe.