Great Country Academician

"What can I help? Do you need this kind of problem-solving method? If you want it, just take it and use it."

Xu Chuan tried his best to suppress his emotions, pretending to be a high school student who heard the news for the first time, and replied in surprise and doubt.

He also didn't expect that what was supposed to appear after the IMO actually appeared earlier.

Now that I think about it, the training time of this national competition has been inexplicably extended by ten days, probably because of this.

Moreover, the university knowledge points in the function class should be prepared for geniuses like them. The country hopes to focus on cultivating a group of mathematicians in this field.

"I really need your help. This mathematical method to simplify the Dirichlet function is very important, and we need you to clarify its key point."

"Also, if possible, it's best to go with me to the Information Security Department. There are dozens of math geniuses and math professors gathered to decipher those encrypted messages. They also need this method."

"After all, the mathematical model has not been established, and this method can greatly simplify the difficulty of deciphering the Dirichlet function encrypted information."

"Or, can you join the Information Security Department?"

Zhang Weiping looked at Xu Chuan and asked.

"Can I have a look at the topics first?"

Xu Chuan didn't answer the question directly, but pointed to the black box in the corner and asked.

He noticed before that there was a thick stack of paper cards in the box, which should all be the kind of questions he just did, but the types may be different.

Although he knew about information security before his rebirth, he hadn't read these topics, so he was quite curious.

Zhang Weiping nodded, walked over to open the black box again with the key, took out a stack of paper cards from inside, and handed it to Xu Chuan.

These paper cards have already been deciphered, and they are from the past, so there is no problem in showing him.

Xu Chuan took the paper card and glanced at the quantity.

The paper used for this kind of card is much thicker than ordinary paper. Based on the thickness of a card of 0.05 mm, there are about forty cards in the stack in his hand.

Just like the topic he just did was a mixture of Dirichlet function + base transcoding, on these paper cards, the topics on each paper card are different, and a lot of mathematical problems are mixed.

Hash function + hash transcoding

New elliptic curve algorithm ECC+symmetric function

RC2/RC4 symmetric algorithm + single compression function

"Are these all accumulated in the past?"

Xu Chuan flipped through the card in his hand and asked.

Almost every question on the card is mixed with at least two or more types of mathematical problems. The questions are intricate and difficult to solve every question.

"Well, this is only a part, which has been selected. The difficulty is average, and some of the more difficult ones are in the Information Security Department."

Zhang Weiping replied: "At present, we intercept dozens of such encrypted messages every day, but most of them are useless data after deciphering, and useful information only occupies a very small part of them."

"But there is often a useful piece of information mixed in with a large amount of useless information. No one knows which piece of information is useful until it is deciphered."

"Manual deciphering consumes too much manpower and energy, so modeling is the only way. The computing power of computers far exceeds that of humans. It can help us decipher encrypted messages in time and catch those people."

Flipping through the paper card in his hand, Xu Chuan handed it back and said, "Although I don't know how your modeling work is doing now."

"But I feel that your current modeling method may be wrong."

"How to say?"

Zhang Weiping frowned, and asked in surprise, if the math ability of the student in front of him hadn't really conquered him, he probably would have turned his head and left.

Establishing a mathematical model to decipher the encrypted information in the first area is the consensus of everyone in the Mathematical Society and the Information Security Department.

Now a senior high school student wants to overthrow this point of view, no matter how you look at it, it is absurd.

Xu Chuan thought for a while, and then said, "Actually, I can't say anything wrong."

"I don't know much about programs and information encryption, but I still know a little about mathematics and mathematical modeling."

"From the paper card just now, I saw a completely different encryption method."

"If I'm not wrong, your approach should be to make a mathematical model for every method that has appeared so far, and then use these mathematical models to solve the encrypted information?"

Zhang Weiping stared at Xu Chuan dumbfounded, and asked, "How do you know?"

"It's simple, it's easy to figure out."

Xu Chuan shrugged and continued: "First of all, the simplified method to solve the Dirichlet function is helpful for your modeling."

"But in fact, the simplified method can only decipher the encrypted information related to the Dirichlet function after modeling the Dirichlet function."

"If your approach is to find the mathematical laws behind these encryption methods, and then make mathematical models based on the mathematical laws, you don't need my method."

"So I guess you are currently trying to model these encrypted messages that have been deciphered, and then use these digital models to find the mathematical scale behind them, or use these digital models to decipher the other party's encrypted messages."

Zhang Weiping stared blankly at Xu Chuan, couldn't help swallowing, what kind of monster is this?

A few simple sentences can clearly guess their work.

Is there really such a terrifying genius in this world?

Xu Chuan ignored Zhang Weiping, and then analyzed: "In addition, I also speculate that these encryption methods may be discarded every once in a while and will not be used again, or they will be used again after a long time. The point can be seen from the question on the paper card."

"The reason I say you have a problem with your modeling approach is that there are nearly endless variations of functions and algorithms."

"Translation, transformation, stretching, rotation, symmetry, asymmetry, as long as you change it a little, it is almost a brand new function. Teacher Zhang, you know this better than me."

"If you want to make a numerical model of all the changes, it is impossible to do it, even if you convene mathematicians from all over the country."

"The most straightforward solution is to find the most basic mathematical laws behind these encrypted messages, and then model them based on that."

"As it is now, as many encryption functions and algorithms as the other party sends out, you can build as many digital models. I personally feel that this method is really not very useful."

"Perhaps there are too many mathematical models, and a hidden mathematical law can indeed be found from them, but it may take a year or two to accumulate."

Xu Chuan shook his head and said, he probably knew why it took two years for this matter to be resolved.

It is estimated that this kind of stupid method was adopted to solve the problem completely.