They're already in university, and the primary school system is only just starting out?

Time flies. It's Friday, May 30th, 3:16 PM.

In a single study room on the third floor of the library, Chen Lin finished reviewing another class's PowerPoint presentation.

He closed his laptop, stretched out a long yawn, and his joints made a series of subtle cracking sounds.

He leaned back in his chair, reflecting on the past week, and a satisfied smile crept onto his lips.

The progress is encouraging.

He has taken notes on all the key points the teacher has taught in his three major courses for the final exams, and he has a general framework in his mind.

If I just thoroughly understand these knowledge points step by step in the remaining month, getting a good score won't be a problem.

It turns out I haven't neglected any of the things I needed to do.

He has already finished learning the remaining chapters five, six, and seven of the book "Python Mathematical Programming" by reading it and typing out the code along with it.

Although he is currently only at the level of a code copyist, he has at least mastered the basic skills of programming.

Chen Lin has made up his mind that when he receives inquiries from design institutes or other online buyers during the summer vacation, he will try to use his programming skills to write the optimization algorithm into a simple Python script.

This way, you can practice your skills and provide more value-added services to your clients at the same time, achieving two goals at once.

Since he used the excuse of final exam preparation, neither Shen Yan nor Yun Qing bothered him anymore.

Shen Yan only sent him a WeChat message on Wednesday night, telling him succinctly that Professor Gu was very satisfied with the progress of her graduate thesis and solemnly thanked Chen Lin again for the consultation he had given her before.

Yun Qing would occasionally send him a few cute cat emojis as a daily routine.

Chen Lin immediately recognized that the background of several of the photos was the same bookshelf of art books in the library where they first met, and that was the same orange fat cat inside.

Chen Lin snapped out of his reverie and glanced at the still bright sunshine outside the window.

Yes, a balance between work and rest is the key to long-term success.

Thinking about the epic battle he was going to have with his three roommates tonight, he decided to give himself a short break and go back to his dorm for a nap to recharge.

……

A dozen minutes later, in room 406.

Chen Lin pushed open the door and found that only Li Houzi was in the dormitory.

The guy was facing his laptop, his brows furrowed, looking worried and scratching his head, muttering to himself as if he were talking about something.

Chen Lin changed into slippers, tiptoed up behind him, and peeked at the screen.

On the screen was a math problem:

A and B start from the same point on a circular track and run at a constant speed in opposite directions. B's speed is half that of A. They meet for the first time after 3 minutes. After that, B accelerates and runs exactly half a lap before meeting A for the second time. How much time passed between their first and second meetings?

Chen Lin glanced at the draft paper next to Li Houzi's hand again. Goodness, it was densely filled with writing, covering more than half a page.

He chuckled inexplicably and blurted out:

"2 minute and 15 second".

"Holy crap!" Li Houzi was so startled by the sudden sound that he almost dropped his pen.

He turned around abruptly, saw it was Chen Lin, patted his chest and breathed a sigh of relief, "Brother Lin, it's you! You scared me to death!"

Then, realizing what he'd just said, he asked, somewhat puzzled, "What did you just say?"

"I said, 2 minutes and 15 seconds," Chen Lin pointed to the question on the screen and repeated, "the answer to this question."

"Really?" Li Houzi moved the mouse with some skepticism and flipped to the next answer.

The next second, his eyes widened.

The answer key clearly states: 【B, 2 minutes 15 seconds】

"Holy crap! Brother Lin," Li Houzi looked at Chen Lin in shock, "You're also taking the civil service exam? You've seen these kinds of practice questions before?"

"No," Chen Lin shook his head and said in a matter-of-fact tone, "I can only do math problems."

"..."

Li Houzi was momentarily speechless at his nonchalant, pretentious tone, but his skepticism prevailed. He rolled his eyes and, still unconvinced, drew another question.

"And this one? Take a look."

Xiao Wang plans to self-study two online courses, A and B, during a 7-day holiday. Each course requires two consecutive full days of study. If he randomly chooses one of the possible arrangements, what is the probability that the three days he doesn't need to study are not consecutive?

Chen Lin glanced at it, and the answer had already appeared in his mind.

"1/10".

Li Houzi's hand trembled, and he almost dropped the mouse. He shakily flipped through the answer and found that it was indeed "1/10".

He wasn't giving up, so he quickly flipped to another question.

A container has an inverted cone at the bottom, 12 cm high, and a cylinder at the top, with the base radii of the cone and cylinder being equal. Water is poured into the container at a constant rate. After 1 minute, the water level is 6 cm high, and after 30 minutes, the container is full. What is the total height of the container in centimeters?

23.5 centimeters.

This time, Chen Lin answered almost instantly again.

Li Houzi stared at the correct answer on the screen, completely dumbfounded, his mouth agape for a long time.

His main problem is that he hasn't touched math for over half a year. If given some time, he believes he can solve these problems himself.

But what's up with Chen Lin being able to answer every question instantly and get them all right?

He stared blankly at Chen Lin, and the scene of their late-night dormitory chat last Sunday suddenly flashed through his mind.

It turns out that what Chen Lin said last week was true.

Originally, he, like Fatty Zhao and Wang Tao, was only skeptical because Chen Lin's clothes that day were the same as the clothes of the man in the photo in that post.

But now, Li Houzi believes it.

I completely believe it!

It turns out that Chen Lin wasn't just bragging when he said he was going to discuss mathematical modeling with Shen Yan that day; he really meant it!

"Brother Lin," Li Houzi swallowed hard, looking at Chen Lin with the eyes of someone looking at an alien, "How come your math suddenly became so amazing? I remember when we were taking the calculus exam in our freshman year, weren't we just struggling together, barely passing?"

Chen Lin directly recited the prepared story, his face displaying a perfectly timed expression of reminiscence and emotion.

"Sigh, it's kind of mysterious. During the summer after my freshman year, I don't know what came over me, but I suddenly became very interested in math. So, for the entire summer and the first semester of my sophomore year, I went to the library whenever I had free time, reading all kinds of math books and studying on my own. And that's how I ended up like this."

Li Houzi was stunned, feeling both confused and impressed.

Self-taught? Is this what they call a genius? That's terrifying!

Chen Lin touched his nose, pondering to himself.

It seems that for most ordinary people, the scenario of a genius suddenly having an epiphany, while sounding a bit far-fetched, is not entirely unacceptable.

He suddenly remembered the news that had caused a stir online some time ago: a female vocational school student won first prize in a top global mathematics competition. At the time, at least for the first time, the whole internet was praising her, and many people believed it to be true.

Although the story was later revealed to be false, his title of "little mathematician" was genuine.

That way, I won't have to worry about being suspected when I change my major.

If even a roommate like Li Houzi, who knows me inside and out, can accept my explanation, wouldn't it be even easier to explain to the school and college leaders?

Returning to the present moment, Chen Lin looked at Li Houzi with curiosity.

"What's wrong with you? You're only a sophomore in college, why are you already doing practice questions for the civil service exam? Isn't that way too early?"

Mentioning this, Li Houzi's face returned to its usual bitter and resentful expression. He sighed and said quietly, "It's all because of what you provoked me."

"what?"

"Look at you, you've become a completely different person lately. You're always out early and back late at the library, taking notes for your major courses more meticulously than anyone else. Now even your math is insanely good," Li Houzi scolded, counting on his fingers. "You're the only one in the dorm studying so much, how can we not feel pressured?"

Chen Lin nodded upon hearing this.

He actually sensed that as well.

Not only Li Houzi, but even Zhao Pangzi, the laziest guy in the dorm who loves to sleep in, has found that the other guy's bed is empty several times this week when he gets up around nine in the morning.

It seems my sudden ambition has given xdm a great sense of crisis.

This is probably what they mean by "afraid that your brother is suffering, yet also afraid that your brother is driving a Land Rover."

"Our Chinese Language and Literature Department already has limited career options," Li Houzi continued to analyze. "If you want to find a decent job, and not a sales job that relies solely on exams, there are basically only two paths: either take the postgraduate entrance exam or take the civil service exam."

"With my grades, I can't hope to take the postgraduate entrance exam, so I guess I'll just have to start preparing for the civil service exam sooner rather than later."

Chen Lin nodded, indicating his understanding. Li Houzi's choice was indeed a true reflection of the reality for most ordinary students in their major.

He patted Li Houzi on the shoulder to comfort him, then turned around to climb into his bed for a good afternoon nap.

However, as soon as he turned around, someone grabbed the hem of his clothes.

"Brother Lin! Don't go!" Li Houzi approached with a fawning expression, holding several sheets of paper filled with drafts in his hand.

"Could you explain the solution process for these questions?"