This is the core problem of the current pair of diplomatic cipher text deciphering work. Although the substitution code encryption mechanism is complicated, there are traces to follow. Frequency analysis attacks can be used. However, the current situation is that this Japanese dialect is difficult to work on.
Hua Luogeng knew Japanese. Not only did he understand it, but he was also proficient in it. He taught himself German, French, Russian, and Japanese foreign languages during his time at Cambridge University. However, he learned Japanese official Japanese, and it was difficult to deal with this Japanese dialect.
Substitution code and language code are one of the main encryption methods in current cryptography. Language code is based on and higher than replacement code. Even if the replacement code is deciphered, the unintelligible language itself is a kind of encryption, allowing a third party to decipher it.
It is difficult for the reader to know the true content of the ciphertext.
The substitution secret consists of single-letter substitution and multi-letter substitution, and is divided into plain text and cipher text.
The principle of single-letter substitution encryption is that each character in the plaintext corresponds to another character in the ciphertext, and the receiver can restore the plaintext by performing reverse substitution on the ciphertext.
The principle of multi-letter substitution encryption is like a matryoshka doll, where plaintext corresponds to ciphertext 1, ciphertext 1 characters correspond to ciphertext 2, ciphertext 2 corresponds to ciphertext 3... until the ciphertext n is limited by the final timeliness of the password.
"In addition to solving dialect Japanese, if we use frequency attacks, I also need manpower. Unfortunately, the students in the Department of Mathematics cannot use them." Hua Luogeng took a puff of cigarette, exhaled white smoke, frowned, and thought carefully about frequency analysis attacks.
As a mathematician, he is very familiar with this method. He even has his own frequency analysis attack method.
Every mathematician is essentially a code-breaking expert.
According to the information given by the Secret Service, the cryptographic system currently used by Japan's diplomacy and military is called red secret. It is an upgrade from the original green secret system. If you want to crack the pile of diplomatic ciphers in front of you, or even the entire set of red secret
The system must solve two problems——
First, understand the meaning of this Japanese dialect itself.
Second, manpower.
Thinking of this, Hua Luogeng stood up and walked towards the door.
"Squeak!" The door opened gently.
"Sir, how are you?" Zhang Zizhong stood outside the door with a look of anticipation on his face.
There were two people standing next to him, one middle-aged and one young, wearing suits, both looking at Hua Luogeng.
"The red secret system uses a language code for Japanese dialects. I don't know which dialect in Japan this is. You have to find it. You can start with popular Japanese dialects, such as Kyoto, Tokyo, Hokkaido, Osaka and other regions, Peking City and Zhutun.
Most of the Japanese military personnel are from the above-mentioned areas, but it is difficult."
Hua Luogeng nodded towards Zhang Zizhong and two men from the Secret Service and said.
"Thank you, thank you very much, Professor Hua. Your words are enough. We are not afraid of difficulties, but we are afraid of not having a direction." After hearing Hua Luogeng's words, the middle-aged man at the head was stunned for a moment, with excitement on his face.
For the first time, I realized the power of mathematicians.
difficulty?
They are not afraid.
What they fear is having no direction.
The work of deciphering the red secret system has troubled the entire Secret Service for several months. They have used almost all kinds of methods, but still have achieved nothing.
They had no idea about this cryptographic system that used the latest encryption mechanism. The Secret Service only knew that this cryptographic system was called Red Secret, and that it used replacement codes and language codes. Other than that, there was no directional gain.
For the intelligence agencies lurking in the dark, the lack of direction to decipher the ciphertext is the most terrifying thing.
I found Hua Luogeng today and unexpectedly gave me directional advice in just one morning.
This made the middle-aged man extremely excited. Apart from being excited, he also felt a sense of... suppression from his IQ.
Hua Luogeng shook his head: "Don't thank me yet. There is still a problem that needs to be solved. I need manpower. The next frequency analysis attack workload is huge. It will take at least 3 months by myself. In terms of the timeliness of the ciphertext,
In other words, this is a failed decipherment."
The timeliness of ciphertext is extremely critical. Unless it is a campaign or strategic-level high-level military intelligence that often spans several months or even years, generally speaking, the timeliness of information such as Japanese troop mobilization and diplomatic exchanges is basically within three days.
Less than a few hours.
It would take more than three months to decipher a piece of intelligence that the Japanese garrison mobilized a regiment to Tianjin...
It's better not to crack it.
Three months is enough for this unit to fight to Taiyuan.
"Professor Hua, please tell me what manpower you need." Upon hearing this, the middle-aged man immediately became energetic. Their department lacks everything, but the most important thing is people.
"My requirements are not high. There should be at least ten people who have received systematic advanced mathematics and cryptography education. Of course, the more the better." Hua Luogeng looked at the middle-aged man and said.
Ten received advanced education in mathematics and cryptography, and Hua Luogeng was able to complete the deciphering work within a month.
There are not many soldiers but good ones...
Well, if it weren't for the scarcity of such talents in China, Hua Luogeng would have wanted 100 or even 1,000. At Cambridge University, he heard his master Hardy say that, like code-breaking work, the more people there are, the higher the efficiency and the shorter the time.
.
silence.
The room suddenly became quiet.
When Zhang Zizhong heard this, he shook his head. The sworn middle-aged man's face froze, and the corners of the young man's mouth twitched slightly.
Is this not demanding?
"Professor Hua, we... don't have this kind of talent, not even one." The middle-aged man shook his head and said truthfully. The Secret Service is full of talents. There are as many people who are proficient in murder and arson as there are crucian carp across the river, but they have received systematic training.
Those with higher education in mathematics and cryptography are zero.
There really isn't any.
"I didn't ask your department to give it. What I meant was that you go find mathematics professors from other universities, such as Peking University, Nankai University, or even National Central University, and gather ten top mathematics talents to establish a dedicated password cracking group." Hua Luogeng sighed.
I breathed a sigh of relief, what he said was so simple, these people are as stupid as college students.
"Professor Hua, you don't know something. Many university professors in China look down on our department. There are also some professors who are unwilling to serve the country and don't want to apply their knowledge to war. No, they are... people like us living in dark corners.
People." The middle-aged man's face showed a hint of helplessness.
"You are the first professor who agrees to help us."
Not wanting to serve the country is the idea of some university professors. Different camps have different attitudes.
This is the belief of a considerable number of university professors who do not want to apply their knowledge to war.
"A group of pedantic people who think they are noble and great!" Hua Luogeng fell into silence after hearing this. After thinking about it, he couldn't help but cursed.
Don’t you want to apply your knowledge to war?
This is not a war for others, but a war of life and death for your own country!
Hua Luogeng loved peace, but he was by no means a pacifist. He always repaid kindness with kindness and revenge with hatred.
When guests come to the door, they sweep the couch to greet them and entertain them with tea and wine.
A jackal comes to the door, closes the door, and entertains them with shotguns.
Treat your friends as warm as spring, and treat your enemies as cruel and ruthless as winter!
The room fell into silence.
"In this case, I will find a way to deal with the talent issue. You should try your best to find other university professors. One of them is one. General Zhang, can you help find it? We will all work together at the same time and strive to crack the red secret in the shortest possible time!
"Just when the atmosphere in the room was stagnant, Hua Luogeng suddenly spoke.
"good."
…
The first-month quiz in early March was a big event for the teachers and students of the school. Yu Hua, who scored 698 points, gained fame and honors and became an idol among the students. Many people gave him the name "Yu Shen"
title.
In order to show their admiration for Yu Hua, many sophomore and first-year students in high school purchased Qiming lighting sources through Cao Wei and Cheng Youping. The sales of Qiming lighting sources were booming, with the order quantity reaching 48 units, almost one for each dormitory.
The degree of Taiwan.
Regarding this situation, Yu Hua had to lament that modern thinking was not applicable to the Republic of China, and the hunger marketing strategy he formulated was declared dead in a sense.
There is no other way. The ultimate goal of Hungry Marketing is to sell more products. However, the No. 4 Middle School market was suddenly occupied by Yu Hua. Who would Hungry sell to?
After accepting this wave of orders, Qiming Light Source is no longer accepting external orders.
For Qiming brand light sources, Yu Hua has no long-term plan. If he can occupy the market of the No. 4 middle school student group, he has achieved his original goal and does not need to invest too much energy again.
However, the Qiming brand light source is not just the end, but the beginning. With the saying "The secret of Yu Shen's good mathematics lies in the arithmetic problem set" spread from nowhere on campus, plus someone on Lin Wan's desk
I discovered a math problem book full of notes. Suddenly, Zhang's third version of the math problem book instantly became a hit among the entire student group and became a book that was crazily sought after by the entire No. 4 Middle School student.
The number of pages full of sincerity, the carefully selected difficult question types, the detailed and meticulous problem-solving process, the unique problem-solving ideas, coupled with Yu Hua's reputation and Lin Wan, the second endorser in the school, Zhang Sanban Mathematics
The question set quickly captured the hearts of all students in No. 4 Middle School.
The science students were tortured by the difficult questions and were in a state of ecstasy. The arts students with poor arithmetic skills were even more confused. They felt that it was extremely profound, but as long as they followed the problem-solving ideas of each question in the question set, they would be able to solve the problem.
I can understand the mystery, and finally realize it, and I have to say something powerful.
It's like this all the way up to the third year of senior high school and down to the first year of senior high school.
Soon, Zhang San's name became famous throughout the No. 4 Middle School.
The popularity of Zhang San's arithmetic problem book was expected by Yu Hua. In order to avoid exposing himself and Zhang San, Yu Hua decided not to sell the arithmetic problem book in person. He specifically changed the sales plan and asked Xu Rui to place it at the entrance of the Fourth Middle School.
We started selling it at the booth and contacted Huangchenggen Bookstore to print 500 more copies and seize the market as soon as possible according to the original plan.
In the class, Yu Hua's identity and status have fundamentally changed due to his first-month quiz score, which was 698. This is a height that everyone in the science class can only look up to, surpassing Zhao Anyuan, who was once the number one in the class, by 63 points.
Although the seat position has not changed, Yu Hua, sitting in seat No. 14, is the uncrowned emperor in the hearts of everyone in the Neo-Confucian class.
Interestingly, Fang Yu, who finally surpassed Zhao Anyuan by 1 point this time, is still the second-ranked player.
With the popularity of Zhang's third edition of the arithmetic problem set, almost everyone in the science class had a copy. Most of the students in the class were either reading the arithmetic problem set or looking at the arithmetic problem set, and they were ranked third in the class and fourth in the school.
Zhao Anyuan, apart from class time, he spends all his free time working on questions.
For ordinary students, the most important thing about the arithmetic problem set is the problem-solving ideas. For top students, the most important thing about the arithmetic problem set is the large number of exercises.
The entire question set, which contains hundreds of questions, is nothing more than a math study question bank that allows people to keep studying and improve their performance.
Tan Qing, who scored 71 points in the arithmetic test this time, is the best example of how to improve his performance by brushing up on questions. The news that Yu Hua tutored Tan Qing in his studies quickly spread throughout the class. Naturally, the word "question tactic" also spread.
Tan Qing is a typical example of the tactics of asking questions. Zhao Anyuan immediately followed and started the trend of asking questions. Fang Yu followed closely. Top students such as monitor Li Fan and Liu Tao did not dare to hesitate. The rest of the students were influenced by the top students. In order to improve
As a result, I had to start the question-sea strategy.
All of a sudden, the whole Neo-Confucianism Class 1 changed from being empty at noon. All the students had eaten and immediately went back to the classroom to study questions. The atmosphere in Neo-Confucianism Class 1 spread to Neo-Confucianism Class 2, and then to Neo-Confucianism Class 1. After a while,
In the entire No. 4 Middle School, a new style of question-sea tactics has begun.
The gentlemen in each class discovered the strange changes in the students. After careful understanding, they found out that the newly released arithmetic problem set was inspected by three arithmetic teachers Luo Wenguang, Tao Ran and Zhu Sui and confirmed that the arithmetic problem set would be beneficial to the students without any harm.
, the arithmetic problem set has been officially recognized by the school to some extent.
Under such circumstances, the sales of arithmetic problem sets became more and more popular. In less than five days, most of the second batch of 500 arithmetic problem books were sold. At the same time, the arithmetic problem sets spread to other students from No. 4 Middle School.
spread.
There are girls' middle schools and Catholic schools nearby, and Chongde Middle School far away, and there are nearly ten schools, large and small.
The area where No. 4 Middle School is located is itself a school gathering area. Most middle schools, vocational schools and normal colleges in Beiping City are located here, and the market potential for teaching and training materials is profound.
Chongde Middle School.
"Jia Xian, come on, come on, come on, look what I bought." Yang Zhenning, a young man, was full of excitement. He ran into the classroom with two arithmetic problem books in his arms. When he saw Jiaxian studying at his desk in the first row, he shouted
While running.
The young man Jiaxian who was interrupted from studying had no choice but to raise his head. He didn't like to be interrupted when studying. In addition, it was the second semester of the first grade and he was very busy with his studies. However, the person who came was his good friend Yang Zhenning.
Putting down his pen, he looked at the excited Yang Zhenning in front of him. The young man rubbed his eyes and asked first: "Zhenning, what did you buy again?"
"The arithmetic problem set is very popular recently. All the top students in Peking No. 4 Middle School are using this, especially Yu Shen who got 698 points in the exam. I heard from people that this is the secret of his excellent arithmetic. I finally bought it.
When the number is 2, I’ll give you one.” Yang Zhenning, a young man, took out a book of arithmetic problems and put it on the desk, explaining.
"You believe it after hearing what others say? It's nothing more than the boastful words of those small printing shops." Young Jiaxian sighed and shook his head helplessly. His good friend was good at everything, but he had a shortcoming: he liked to follow trends and be fooled.
Yu Hua, the student from Peking No. 4 Middle School who scored 698 points in the first month's quiz, knew it, but could his high score come from an unknown arithmetic problem book?
impossible.
He used to like buying books from street stalls at the school gate. He originally thought he could learn knowledge and expand his horizons, but he never expected that the quality of these street stall books could not be improved at all.
He has suffered enough losses, and he no longer believes in this so-called listening to people's words and selling books on the street.
Every day, it's different.
"Hey, Jiaxian, this time is different, you will know after reading the question book." Young man Yang Zhenning chuckled.
"Okay..." Young Jiaxian shook his head, picked up the new arithmetic problem book that smelled like a book, took a look at the cover and thickness, and felt that the workmanship of this problem book was much better than any previous pirated books.
With a hint of interest, the young man opened the first page and saw a series of function questions. He was stunned for a moment. There was no preface, just the main text.
The young man Jiaxian frowned slightly and turned his eyes to the first function question. After taking a look at it, he made an evaluation.
Difficulty is medium.
This function question is relatively simple for senior high school students, but it is moderately difficult for young Jiaxian, a first-year high school student, and it will take a certain amount of time to solve.
After reading the question, the young man Jiaxian silently calculated in his mind. He had no clue for the moment and turned his attention to the process of solving the problem. Soon, the detailed and meticulous problem-solving process appeared, making his whole person suddenly enlightened.
This question turns out to be like this.
After watching the problem-solving process, young Jiaxian realized three things clearly in his mind and moved his gaze downwards. He originally thought it was the second problem, but the idea for solving the first arithmetic problem appeared.
Problem-solving ideas?
Young Jiaxian was slightly confused and continued reading. After reading the problem-solving ideas, he immediately understood why this question was done and what knowledge points it tested.
Interesting and interesting.
After reading the first question, young Jia first looked at the second question and quickly immersed himself in it. Some arithmetic knowledge points that he did not understand at first were quickly understood with the help of the arithmetic questions.
I don't know how long it took, but suddenly, the young man Jia Xian felt someone poking his arm. He raised his confused head. Standing in front of him was his friend Yang Zhenning.
"Jiaxian, how do you feel after watching it for ten minutes? If it's not good, just give it back to me." The young man Yang Zhenning squeezed his eyes, looked at the confused young Jiaxian, and said jokingly.
return?
Young Jiaxian quickly held the arithmetic problem book in his arms, treating it like a treasure. He glanced at his friend and took a deep breath: "This book... is of great value! Zhenning, how did you get it?"
"I grabbed it from a boy's street stall. There were very few books, but many classmates bought them. You don't know, but I spent a lot of effort to grab a copy. I was about to leave when I suddenly remembered that you didn't have it yet.
Go back and grab the second book." Yang Zhenning, a young man, responded, telling his true experience of buying books.
"Zhen Ning, thank you, I owe you a favor." When young Jiaxian heard this, he was moved and did not mention the money, but said solemnly.
I owe you a favor.
This is the young Jiaxian's evaluation of the value of this book. He would not buy those pirated books even if they cost 10 yuan a copy, but this book would not matter even if it cost 10 yuan a book, because this book of arithmetic problems
Worth the price.
"Study hard. We said that we want to become the greatest physicist in the world. We must strive for this goal and never stop for a moment." The young man Yang Zhenning did not refuse, nodded, and shook the math problem book
Shake, smile.
"come on!"
The young man nodded solemnly.
The sunshine in early March of 1937 fell on the classroom of Chongde Middle School and on these two teenagers.
…
The popularity of arithmetic problem sets continues.
As time went by, after the arithmetic problem set spread from No. 4 Middle School to the entire school gathering area, it received unanimous praise from arithmetic teachers and top students in major schools. The sales of the entire problem set went up to a higher level and became very popular.
.
However, this explosion has basically nothing to do with Zhang San as the author. What is supposed to come has come.
It was mid-March, and Huangchenggen Bookstore, which was responsible for printing the arithmetic problem book, discovered the popularity and potential of the arithmetic problem book, and immediately tore up the printing contract for the third batch of 1,000 copies, immediately pirated the arithmetic problem book, and sold it externally.
.
Outside the gate of Tsinghua Park Second Campus.
"Sir, that fellow Zhang Fu was so unreasonable that he tore up our printing contract. Ruizi went to argue with him, but he kicked him out." Xu Rui stood beside Yu Hua and walked forward, breathing heavily and looking angry.
.
"It doesn't matter, are you injured?"
Yu Hua, who had just come out of Tsinghua University West Campus to finish his studies today, heard these words, Zhang Fu's face that once longed to save his life appeared in his mind, he shook his head slightly, and didn't have much reaction. In essence, it was the Huangchenggen Bookstore for pirates.
, piracy is normal nowadays.
To expect Huangchenggen Bookstore to stick to its bottom line is worse than to expect a dog to dislike the meat buns that are brought to your mouth.
You must have this kind of awareness when you find a pirate to print a question book.
Yu Hua does not blame Huangchenggen Bookstore and Zhang Fu. Of course, Huangchenggen Bookstore will have nothing to do with him in the future.
Life or death, let it be your fate.
"No, Mr. Zhang Fu seemed to be thinking of you, sir, and didn't use violence against Ruizi. It's just that I was really angry. The pirated workshops and bookstores in the north and west of the city continued to close down. Only Huangchenggen Bookstore relied on your title, sir.
After surviving, not only did he not be grateful to you, but he tore up the printing contract." Xu Rui shook his head repeatedly: "Zhang Fu is too hateful and unbearable to be a human being!"
"Don't be too angry. He's just a stranger. How many copies of the collection have been sold in total?" Yu Hua looked at the anger on Xu Rui's face, smiled, and patted Xu Rui's shoulder.
Since becoming a disciple of Hua Luogeng, Yu Hua has left all the sales of arithmetic problem books to Xu Rui and no longer pays too much attention to it.
"There are 1,259 books in total, and there is no title book at home. All the legal currency I received was converted into silver dollars according to your request. I exchanged 1,100 oceans and kept them at home. The legal currency is becoming worthless." Xu Rui gave the situation like a treasure trove.
1100 oceans, no more, no less.
The shortfall of 5,000 is still more than 3,000.
After hearing this, Yu Hua silently calculated and had an idea: "How is the situation at home? By the way, is there any news about the matter that I asked you to inquire about?"
The depreciation of the legal currency has already begun, which is inevitable. Yu Hua had already asked Xu Rui to exchange the legal currency for silver dollars as much as possible after receiving the legal currency.
"I'm fine at home. Ruizi has already inquired about the two Japanese. One is Fujita Shintada, a soldier at the Japanese Pavilion in Dongjiaomin Lane, and the other is Horikoshi Jiro. I don't know what he does." Xu Rui glanced around, but there was nothing else.
Someone else whispered.
"Jiro Hikigoshi?"
When Yu Hua heard the first name, he had no reaction for the time being. After hearing the second name, he was stunned. Isn't this the designer of the Zero fighter?