Chapter 195 I Have a Very Awesome Roommate

"So you want us to help you improve your plagiarism detection tools?"

"Well, it's a great achievement if you get it done. I guarantee you a scholarship... Okay, you don't need a scholarship either. When you return to Shanghai, I'll treat you to dinner. How about Jin Mao Penthouse?"

"Wow, is it so luxurious?"

"Yes, this is a big project. How about doing me a favor?"

"Okay, I'll give it a try, but let me tell you first, I'm not as good at programming languages ​​as you think."

"You are more talented than you think." Li Yan shook his head. Although Wu Bin had not helped him solve any actual coding problems, Li Yan was too confident about his academic ability. Everything you have studied can reach a state that ordinary people cannot understand.

Both of them have resolute personalities, so after dinner, Wu Bin and Lin Ziqi followed Li Yan directly to the student union office.

[Should the mission of the times and gather the power of youth! 】

As soon as you enter the door, there are various party newspapers and propaganda posters all over the wall. It can be said that it is quite popular and makes people feel full of mission at a glance.

Under the leadership of Li Yan, Wu Bin met Tang Chengwen, the vice chairman of the Disciplinary Inspection Department.

When he learned that Wu Bin was here to help solve the problem, Tang Chengwen immediately expressed a warm welcome.

Last semester, Wu Bin learned from Li Yan that the student union at HKUST does not have the legendary "bureaucracy". Everyone regards the student union as a place to practice their abilities, so the atmosphere is very good.

Although Wu Bin had also heard that some students would become official after joining the student union, and even do some cliquey and private things after gaining power, it was really hard for him to imagine what that would be like.

After exchanging a few polite words, Tang Chengwen described the phenomenon and scope of cheating to Wu Bin.

Wu Bin nodded with understanding.

In short, he does not need to study how plagiarism occurs. He only needs to develop a better automatic program to effectively find the plagiarized code from a pile of submitted assignments.

'interesting'

This reminded Wu Bin of a small game he had encountered on the forum. The content is that you are given two C codes and you rate the similarity between them. It is an effective training for language understanding.

"let me try."

Wu Bin, a master in the coding world, has seen a lot in major forums, but now that he is at HKUST, he really doesn't know what kind of Taoist Montenegro demon he will encounter.

"So smart..."

After finishing several sets of codes, Wu Bin's lips curled up. The person who wrote the code obviously knew that someone would detect the similarity of the codes, so he deliberately made the code complicated. If it had to be manually identified one by one, it would be really time-consuming and laborious.

In addition, there are many students who directly copied the code. They are probably just trying to get something for nothing. Although this is human nature, it is definitely not a good behavior.

‘However, the design of this experiment is indeed a bit boring. I guess most students are not interested in doing it seriously. ’

But what's wrong is wrong, and developing this habit will definitely not do any good for your studies.

"How is it? Is it difficult?" Tang Chengwen, who was standing behind him, asked.

"It's okay, just give me some time."

"That's great." After Tang Chengwen finished speaking, he asked Li Yan in a low voice: "Do you still know friends from the school?"

"Oh no, he is my classmate from the School of Physics."

"Is Wu Yuan so omnipotent now!?" Tang Chengwen asked in shock.

"No, it's just him. He has a wide range of interests."

"excellent……"

While the two were chatting, Wu Bin was doing problem analysis. In essence, the problem of checking the copied code is actually given two codes P1 and P2.

The "distance" between d(P1, P2) is required. The smaller the distance, the greater the suspicion of plagiarism.

The prerequisite for solving the problem is naturally to find the problem. After looking at so many codes, Wu Bin almost made a summary in his mind.

The most commonly used method is to modify irrelevant information such as comments, variable names, capitalization, etc. Next comes code rearrangement, style modification, etc. For example, use the indent tool to filter the code. You must know that everyone has their own programming style. Such a change will look very different to the naked eye.

The other two are more technical. One is to add or delete redundant components in the code, such as adding some useless code or deleting some printed debugging information.

The second is to equivalently rewrite data structures, loops, and local codes, and split and merge functions.

To find out the problem, the first thing Wu Bin needs to do is to optimize the compiler to compile the code. This is very important. Many manually modified equivalent codes can be optimized into the same binary code, and then the instruction sequence of the function can be obtained.

In this way, except for the most technical method of equivalent rewriting of data structures, loops, and local codes, the other three cheating methods are useless.

Because in the eyes of the compiler, no matter how you indent or adjust, the compiled function will look the same.

Seeing Wu Bin typing code on the computer, Tang Chengwen and Lin Ziqi both opened their mouths.

Although Lin Ziqi knew that Wu Bin was very good at designing programs when she was in the laboratory, she was still shocked when she saw it with her own eyes.

'This proficiency is too high...'

After modeling the similarity of the program into a maximum weight matching problem on a bipartite graph, Wu Bin turned back to Tang Chengwen and said, "I want to copy the rest back to the dormitory and work on it. It will probably take a lot of time, is that okay?"

"Of course it's no problem." Tang Chengwen nodded repeatedly, "Then I would like to thank you in advance for helping us solve such a big trouble."

Although Tang Chengwen couldn't understand what Wu Bin did, his calm and calm demeanor made him feel that someone with no ability really couldn't pretend.

"polite."

Wu Bin has been reading physics papers crazily in the past week. Now that he has stopped to do something else, he feels good. He even feels that some new inspirations are already being conceived. If he works harder, he can come up with it.

After leaving the student union, Lin Ziqi left the team and went to the laboratory first, while Wu Bin and Li Yan returned to the dormitory.

Turning on the computer, Li Yan turned to Wu Bin and said: "Now I finally understand why so many people like to start with "I have a friend, I have a classmate, and I have a colleague".

Before Wu Bin could speak, Chen Anzhi on the side interrupted: "What, Wu Shen took you to pretend to be B and took you flying?"

"Yes, I guess it won't be long before the legend spreads among the student union that I have an awesome roommate."

"What are you pretending to be? Let me tell you." Chen Anzhi looked curious.

"It's not solved yet, don't listen to his nonsense." Wu Bin said as he walked to Chen Zhian's desk and glanced at the electromagnetic problem he was working on.

"Boss... don't look at me like that. I'm under a lot of pressure." Chen Zhian said pitifully.