The salted fish life of the door-to-door son-in-law

"You are husband and wife, how can you not know what your husband knows?" the principal asked Zhou Xiafei curiously.

Zhou Xiafei was a little speechless, no wonder she was there, the most important thing was that Liu Zhicheng knew too many things, and now Zhou Xiafei was not sure what Liu Zhicheng knew.

Moreover, Liu Zhicheng has already reached the top level of everything he knows, so Zhou Xiafei really dare not say that Liu Zhicheng can't do mathematics, so after thinking about it, Zhou Xiafei said to the old principal: "Principal, that's it, my family, The things he knows are too complicated, it seems that there is no one in this world who can't do it, I'll call him now and ask him, what do you think?"

After hearing Zhou Xiafei's words, the old principal nodded and said, "Okay, because this matter is more complicated, and it is related to the honor of our Kyoto University. As you know, there has never been a lecture in our Kyoto University that was not taught by our school's tutor. This time, if we can't solve his conjecture, we will break the school history, and it will be broken by a foreigner, and I will absolutely not allow such a thing."

After listening to the old principal's words, Zhou Xiafei also nodded very seriously, and said to the old principal: "I'll call now!"

After finishing speaking, Zhou Xiafei took out her mobile phone and dialed a call to Liu Zhicheng. At the moment Liu Zhicheng was lying on the school bench and sleeping. After being woken up by the phone, he glanced at the caller ID. Zhicheng reluctantly picked it up.

"Ah Cheng, tell me the truth, do you understand mathematics?" Zhou Xiafei asked straight away.

This question stunned Liu Zhicheng, "Looks like, I should know a little bit." Liu Zhicheng replied uncertainly, because Liu Zhicheng didn't know the reason why Zhou Xiafei asked this question.

"That's good. Now that you understand it, you must be proficient. I haven't seen anything you understand but are not proficient in." Zhou Xiafei continued into the phone.

"It should be a little bit better than the mathematicians in this world." Liu Zhicheng was very immodest.

The conversation between the two was heard by the old headmaster of Kyoto University. This time, the old headmaster didn't dislike Liu Zhicheng's big talk and bragging. Instead, he excitedly urged Zhou Xiafei to hurry up and ask if Liu Zhicheng could replace his school in the game.

"Our old principal made a request to me, asking you to help our school once to solve a worldwide math problem. It's just a conjecture, waiting to be confirmed." Zhou Xiafei listened to what the old principal asked Liu Zhicheng to do for him. He repeated the words of the old principal to Liu Zhicheng.

After Liu Zhicheng heard this, he said to the phone with some reluctance: "The old man is not very knowledgeable, don't get involved with him, be careful that he will lead you astray."

Liu Zhicheng didn't answer Zhou Xiafei's words directly, but instructed Zhou Xiafei instead.

"How do you say it? Our old principal has published dozens of wonderful articles in internationally renowned academic journals. You mustn't doubt our old principal's level." Zhou Xiafei complained for the old principal.

"Now is not the time to doubt my level, ask him if he is willing." The old headmaster was sweating on his anxious forehead.

"How about it? Do you agree or not? Play for our school and meet that foreigner for a while, otherwise our school will be ashamed." Zhou Xiafei finally got to the point.

With Liu Zhicheng's laziness, he is too lazy to care about whether you are ashamed or not, but this is a question Zhou Xiafei asked himself, so Liu Zhicheng tentatively replied: "As far as your school's mathematics level is concerned, it is probably the same. , help your school once, can you help the second time? So everything depends on yourself.”

Zhou Xiafei saw that Liu Zhicheng disagreed, so she spread her hands helplessly at the old headmaster, but the old headmaster suddenly said to Zhou Xiafei: "That foreigner seems to have another apprentice, he should be your suitor, what is his name James!"

After hearing this, Zhou Xiafei was a little surprised. He didn't expect that little foreigner to chase after him to the school, and the old principal continued to add: "The foreigner also said that as long as he loses to us this time, he will never come We Huaxia! If he doesn't come, his apprentice probably won't come either."

Thinking of the blond-haired and blue-eyed look of that little foreigner, Zhou Xiafei became angry for a while, so Zhou Xiafei said directly to the phone: "I will make the decision for you. Come to our school tomorrow morning and teach that girl a lesson for our school." foreigner!"

After finishing speaking, Zhou Xiafei hung up the phone directly, and said to the old principal: "Principal, don't worry, that foreigner will definitely be severely taught by my husband. I will make the decision for my family."

After hearing Zhou Xiafei's words, the old principal clapped his hands suddenly, and said to Zhou Xiafei: "It's really great, as long as your husband can help our school teach that foreigner a good lesson, I promise, I will teach you and your husband directly." The position, a professor in his twenties, is unprecedented!"

Although Zhou Xiafei is also a professor at Kyoto University, she has the word "Honor" on her head. Whether she has honor or not is a world of difference.

At [-] o'clock the next morning, Radhiskov's speech has officially started, because this is a worldwide mathematical problem, and it is the international mathematics master Radhiskov who personally gave a speech and answered this international mathematical problem on the spot , so the whole venue was crowded with people.

After getting up from the Shenglong Hotel, Liu Zhicheng glanced at his phone and sat up suddenly from the bed, because it was already a quarter past eight, and there were seven missed calls on his phone, all of which were from Zhou Xiafei.

Chapter 924 This is what you said

"My conjecture is the five-color conjecture. Once, when I was studying the world map, I discovered a curious phenomenon, that is, I found that each map can be colored with five colors, so that countries with common borders can be colored differently. s color."

This is a worldwide mathematical problem, also known as the five-color conjecture, which directly made Rajskov a world-class mathematics master.

"Next, I'll prove my conjecture to everyone!" Then Rajiskov wrote directly on the blackboard, filling the entire blackboard with eloquence.

"This is my proof, and it is also the greatest proof in the world. My conjecture has been listed as one of the top ten modern mathematical conjectures in the world. This is my greatness. Let me explain to you why it is so solved. Of course, I guess you don't understand either."

What Rajiskov said was ugly, but his own strength lies there. People in China are not yet capable of posing world-wide mathematical problems. Therefore, although people were upset, they did not express anything.

But just when Radhiskov was speaking freely, a very discordant voice sounded, Liu Zhicheng stood up lazily, and said to Radhiskov on the podium: "What kind of bullshit theory are you talking about? One color, only four colors are needed.”

After seeing Liu Zhicheng appearing in the crowd, Zhou Xiafei finally breathed a sigh of relief. She thought Liu Zhicheng had forgotten about it, or simply overslept.

It's normal for Liu Zhicheng to forget things, and it's even more normal for him to oversleep. With Liu Zhicheng's lazy character, Zhou Xiafei doesn't feel curious about what he does.

"Ignorant child! Why do you question my conjecture? What qualifications do you have to talk to me!" Rajskov was talking about the exciting part when he was suddenly interrupted by Liu Zhicheng, so Rajskov was very angry.

"He may not have been qualified before, but from now on, he has it. He is the youngest professor of our Kyoto University, a professor of mathematics!" The old president of Kyoto University suddenly came to the stage and said to Rajiskov.

"You!" Rajiskov pointed at the nose of the president of Kyoto University, but did not leave.

"Okay, you go down, you think you are a master of mathematics by putting forward a conjecture, but you don't even know whether the conjecture you put forward is correct or not, what kind of master of mathematics are you!" Liu Zhicheng said very unpleasantly.

After hearing this, Radhiskov said directly to Liu Zhicheng angrily: "Okay, if you have the ability, you can prove to me that only four colors can be used, come here! If you can't prove it, I want you to tell me in public Kneel down and apologize!"

"If I can prove it, then you and your people will get out of China forever. China doesn't need such an arrogant person like you." Liu Zhicheng also said to Rajiskov.

"Okay! It's a deal!" Radhiskov didn't believe that the young man in front of him could have the ability of the world's top mathematics masters, not to mention that even the world's top masters could not prove his theory .

"Well, let's wait and see." After Liu Zhicheng stretched lazily, he walked slowly to the podium. He glanced at the blackboard covered with words, and said to a student below: " Can you come up and wipe all this mess for me!"

The student was already upset with Rajiskov, so he walked up happily and erased all the words on the blackboard.

When the student was going down, Liu Zhicheng asked him, "How does it feel to erase all those words?"

"Cool!" The student replied after thinking for a while.

"Okay, let me show you what the four-color conjecture is, not the five-color conjecture." After speaking, Liu Zhicheng began to write on the blackboard.

Assume, any polyhedron, 4, 5, 6....hedron, another angle, called polypoint body, 4, 5, 6.... point body, tetrahedron (tetrahedron) 4 colors, Each face is adjacent to the other 3 faces, and the five-point body can be regarded as adding a point to the four-point body.

Of course, you can think in reverse, the five-point body is reduced by one point to become a four-point body, and the same is true for 6, 7, 8... point bodies, and we know that any N+1 point body can be changed from N point bodies Come on, of course, you can also think in reverse.

The following analysis, if the four colors of the N-point body can be dyed, when adding one more point to the N-point body (or the process from N+1 point body to N-point body...), it is actually equivalent to adding a pyramid (or like a pyramid, the bottom surface The uneven one, the bottom surface has characteristics and cannot contain dots, otherwise the dots will be reduced).

Because it is reversible, it can be changed from N+1 to N, so it must be able to change from N point body to N+1 point body, and the bottom of the pyramid and the disappearing surface of N point body can look in the mirror.

The new adjacency has not changed fundamentally.

The facing surface of the disappearing face of the N-point body is subtracted by one facing face, and another facing face is added. Similarly, the side face of the cone is subtracted by one facing face, and one facing face is added. Because of the existence of triangles, the pyramid will not introduce five adjacent faces, N The face of the face where the point body disappears, the side face of the cone and the other three faces.

These five faces will not be adjacent to each other (because the side of the cone is only adjacent to three faces), and the facing face of the disappearing face of the N-point body and the other four faces (excluding the sides of the cone) will not appear in pairs of five faces Adjacent phenomenon (known condition), the adjacent relationship between 4 faces and n faces has not changed fundamentally, that is, the phenomenon of "five faces adjacent to each other" will not appear.

The four-color theorem: Subdivide the plane arbitrarily into non-overlapping areas, and each area can always be marked with one of the four numbers 1, 2, 3, 4, without causing two adjacent areas Get the same number, that is, there are at most four two-by-two adjacent regions.

After Liu Zhicheng finished writing, he began to explain. Soon, Liu Zhicheng used easy-to-understand principles to explain how he guessed the four-color conjecture to everyone, so that many people below understood that the four-color conjecture is in the end. How did it come about.

After the explanation, Liu Zhicheng threw the chalk casually, and said to Radhiskov: "How about it, are you convinced, do you understand now? Your guess is wrong at all, and this is the real solution to your guess. "

When Liu Zhicheng explained just now, Rajiskov also listened to it, and he also deeply understood that he was wrong, but now is not the time to admit his mistake, because he can't afford to lose that person.

So Radhiskov said to Liu Zhicheng: "Although you can solve my conjecture, I don't recognize your answer. Besides, what are you? In the international mathematics community, what qualifications do you have to answer the question?" My conjecture! If you are capable, you can also propose a conjecture! I will solve it for you in minutes!"

After hearing this, Liu Zhicheng smiled at Radhiskov and said, "You said that!"