CHAPTER 415: CHAPTER 141 YES, THAT’S HOW IT IS!

The next day, early morning, Spoon Garden Cafeteria.

"I thought about it a lot last night, and I’m definitely not a mathematics genius. Because I’m not like you, nor like that man.

For example, you guys could easily get full marks in high school mathematics, but I couldn’t. I often made mistakes, both in the past and now. It’s always been like this.

And at my age, I can’t be as shameless as you. So don’t expect me to say pleasant things in front of Academician Yuan like you and Keke.

If Academician Yuan asks me something, I will answer truthfully. If I know, I know; if I don’t, I don’t. I won’t pretend to understand, nor pretend not to understand. Don’t get your hopes up too high."

While having breakfast, Qiao Xi gave Qiao Yu a heads-up.

Her words made the initially confident Qiao Yu a bit uneasy.

Qiao Xi thought Qiao Yu was a bit boring, making such a fuss over a trivial matter involving a great academician.

Qiao Yu, on the other hand, hoped that Qiao Xi could be valued by Elder Yuan, and come to Beijing in the future, so that they could not only be closer to each other but also discuss mathematical topics and then mock her.

After all, no matter how strong Qiao Xi was, she couldn’t be stronger than him.

"Got it! Anyway, we’re both self-taught, but I still think that anyone who can casually understand Schulz’s paper must be gifted."

Qiao Yu kept his head down, eating porridge and buns, too lazy to argue with Qiao Xi anymore. Anyway, they’d know once they got to Huaqing.

The two places were very close, and there was no rush, so Qiao Yu didn’t use the number Director Tian gave him, he just brought Qiao Xi directly to Huaqing’s Qiuzhai.

Actually, apart from that section of the road, the scenery in both campuses was quite nice, especially the road leading to Qiuzhai in Huaqing.

But the most important thing was that even though it was already July, while the morning in Star City was hot enough to make one sweat, the temperature in Beijing was only around twenty degrees, making the walk very comfortable.

Twenty minutes later, Qiao Yu brought Qiao Xi into Elder Yuan’s office.

To his surprise, Professor Tan was also there.

After the small talk, the four of them sat on the sofa prepared for guests, each with a steaming cup of tea in front of them.

Qiao Xi immediately represented Qiao Yu and sincerely apologized to the elder: "Elder Yuan, yesterday Qiao Yu was indeed reckless. Actually, I can at most say that I have an interest in mathematics.

I really don’t think I have much talent. More than ten years ago, when I was in high school, I didn’t show much ability in mathematics either. I even found it hard to get full marks on high school exams."

Elder Yuan smiled and shook his head, saying, "Let’s not talk about that, whether or not you have a talent for mathematics is a small matter. But the idea you proposed yesterday, both Lu Yuan and I found it very interesting. Today, we just want to have a casual chat with you."

This statement also reassured Qiao Xi, making her relax.

Being a mother, she was still afraid that because of herself, the big shots might be harsher on Qiao Yu.

So the four of them chatted about various topics, and then the elder stylishly praised Qiao Yu, slowly turning the conversation to mathematical topics.

"By the way, Qiao Xi, yesterday Qiao Yu mentioned that you could independently understand Schulz’s paper?"

Professor Tan asked casually.

Qiao Xi thought for a moment and answered earnestly, "Partly. I can’t say I completely understand it."

"Then do you have a foundation in advanced mathematics?" Professor Tan continued.

"I’ve occasionally flipped through Qiao Yu’s borrowed mathematics books, including Linear Algebra, Calculus, and Mathematical Analysis. I’ve been reading more literature lately."

Qiao Xi replied casually.

"Oh, if you had to choose one that you find more interesting between Linear Algebra and Calculus, which would it be?"

"It would be Linear Algebra."

Qiao Xi thought for a moment and said.

Professor Tan smiled, glanced at Elder Yuan, thought for a moment, and said, "There’s a sequence of numbers, the first three numbers are 1, 3, 7... According to this pattern, what would you say the fourth number is?"

Upon hearing Professor Tan ask a question, Qiao Xi didn’t react much, but Qiao Yu immediately sat up straight.

"23." Qiao Xi casually gave an answer.

Tan Lu Yuan nodded and smiled as he asked, "Think again, if there’s a 3X3 square grid, starting at the top left corner and ending at the bottom right corner.

The rule is you can only move right or down, without drawing it, what is your first instinct on how many different paths there are from the start to the end?"

"6 paths." Qiao Xi smiled and answered.

Tan Lu Yuan nodded and then noticed that Qiao Yu seemed to be glaring at him...

Initially a bit surprised, but he quickly understood, maybe it was because he thought the questions were too easy?

However, he didn’t mind, he just smiled and asked, "Qiao Xi, have you studied graph theory?"

Qiao Xi shook her head and said softly, "No, I’ve never encountered it."

Tan Lu Yuan said with a smile, "No problem, let me explain two concepts to you. In graph theory, there is a basic structure called an undirected graph, consisting of vertices and edges, where edges represent connections between vertices and are characterized by the absence of direction.

For example, if there is an edge u, v, it can connect from u to v, or from v to u, and the relationship is equivalent between them.

A cycle refers to a path starting from a certain vertex, passing through a series of edges and vertices, and ultimately returning to the starting point. Note that in a cycle, vertices other than the start and end points cannot be repeated. Can you understand these two concepts?"

Qiao Xi nodded, as if it wasn’t difficult for her.

"Now, there is an undirected graph with nodes A, B, C, D, and edges A-B, B-C, C-D, D-A, A-C. Do you think this undirected graph has any cycles? If so, how many cycles do you think it has?"