"Zhiwen, why are you targeting me? I didn't say I wanted to participate in the ACM World Programming Competition?" Wu Zhe joked about Shen Zhiwen.

Shen Zhiwen didn't reply, and just stared at Wu Zhe. Being stared at by Shen Zhiwen, Wu Zhe could only surrender.

"Zhiwen, is this your attitude when asking for help? This is almost a threat." Wu Zhe said with a smile.

While they were joking, Wang Chao cursed: "dig." Then the computer crashed and the screen went black.

"Young Master Wang, what have you done again? Watching a movie? You are still young, don't do anything that is not available?" Huang Minghai teased Wang Chao.

Although it was a joke, a few people were still very curious. After all, the computer was equipped by Shen Zhiwen, a master, with high configuration, and the protection in his dormitory was written by Chen Zhiwen and Wu Zhe themselves, and Wang Chao's computer The level is not low either. If it is a computer virus or someone hacked, it is impossible for Wang Chao to not even react at all.

"Bah, you're just watching a short movie? I ran the program I wrote, but it didn't work right after I ran it. I still can't figure out the reason." Wang Chao said with a red face. Damn it, you can't be good or bad either. You must be considered a genius! If you write a program that can shut down your computer, it would be strange if Wang Chao didn't blush.

"Zhiwen, come and help me take a look, what the hell is this?" Really unable to find the reason, Wang Chao had no choice but to look for Shen Zhiwen.

Shen Zhiwen came over to take a look, and then checked it carefully. He pressed the confirm button to run, but the computer was still down.

I checked inside and out and found no fault. But as soon as I ran the program written by Wang Chao, it would crash. But Shen Zhiwen checked the code and found that the logic was ok and there was no problem with the coding. There was no problem with the system. An error is reported, but it just cannot run. This is the first time I have encountered this phenomenon.

"Wang Chao, stop it now. The school selection exam is about to begin. You and Wu Zhe will take the exam first, and Zhiwen and I will help you find out what's going on first?" Huang Minghai said after looking at the time.

"Well, let's take the exam first." Wang Chao also knew the importance.

He turned around and called Wu Zhe again: "Let's go, Azhe!"

"You go alone! I won't go." Wu Zhe replied with a smile.

Several people looked at Wu Zhe with puzzled faces, "You're not going? What does this mean?" The announcement was made at Shuimu University at that time. If Wu Zhe didn't participate, they would not be able to see people from other universities in the future.

Looking at the expressions of the other people, Wu Zhe knew he couldn't joke anymore. He said with a smile: "Two days ago, the college informed me that I don't have to take the selection exam. I'm afraid of delaying Kaixin.com, so I can go directly to the Qiu competition. So, Wang Chao, you You need to go alone and take the exam well, I am optimistic about you!"

"MMP!" Wang Chao just wanted to yell.

When Shen Zhiwen and Huang Minghai saw that it was not Wu Zhe who was not participating in the Qiu competition, they were relieved. They both began to tease Wang Chao.

Before Wang Chao went out, he could only give a middle finger gesture.

After Wu Zhe waited for Wang Chao to go out, he also began to check the program written by Wang Chao. There was no problem with the code. Wu Zhe slowly looked at it, and the logic seemed to be consistent. Wu Zhe frowned and started thinking.

"Huh? This place seems familiar!" Wu Zhe's eyes lit up, and then he looked for Wang Chao's notebook. Looking at his modeling ideas, his mind was running at high speed.

"Zhiwen, stop working. I should know the problem." Wu Zhe said.

"What's the problem?" Shen Zhiwen asked.

"Haha, Wang Chao is too ambitious. Look at these four indicators. Rising - falling - consolidation - shock, and then bring in other parameters to make a judgment on the rendering results. What does this kind of judgment look like to you?

"Four-color conjecture?" Shen Zhiwen reacted immediately. "Fuck, what did Wang Chao think? It would be strange if this machine doesn't go down."

"I guess he didn't realize it himself and thought that the logic was self-consistent. It would be strange if it didn't crash. The amount of calculation is too large and it may require supercomputing to complete." Wu Zhe said with a smile.

"And not only did he figure out a world-wide difficult problem called the four-color problem, but he also figured out the Sitapan conjecture involving graph theory. I don't know whether he is a genius or a fool. Two unproven conjectures can win To apply it, and the logic is self-consistent. I will force him to prove it when he comes back." Wu Zhe said fiercely.

"Why can't it be used without proof? 1+1=2 hasn't been proven yet? It can't be used as usual. Besides, hasn't the four-color problem been proven on a computer?" Huang Minghai said beside him.

"That's just the calculation of the four-color problem 10 billion times without making any mistakes. It's not over if I haven't given a proof in mathematical logic for a day." After saying this, Wu Zhe became interested, picked up a pen and scratch paper and started to prove it.

——————

In 1852, when Guthrie, who graduated from the University of London, came to a scientific research institute to do map coloring work, he found that each map could be colored with only four colors. He wondered whether this phenomenon could be proved mathematically. ? It can only be said that he was too full to eat. Guthrie and his brother really got into research. In the end, they even hooked up with his brother's teacher, the famous mathematician De Morgan, but many of them died. Haven't researched it yet.

It was not until 1872 that Kelly, the most famous British mathematician at the time, formally raised this question to the London Mathematical Society, and the four-color conjecture became a matter of concern to the world's mathematical community. Many first-class mathematicians in the world have participated in the four-color conjecture. The Great War. In 1880, mathematicians used the method of reductio ad absurdum to prove: The general idea is that if there is a regular five-color map, there will be a "minimum regular five-color map" with the smallest number of countries. If the minimal regular five-color map If a country has less than six neighboring countries, there will be a regular map with a smaller number of countries that is still five-color. In this way, there will be no minimal five-color map with a minimum number of countries, and there will be no regular map. Five-color map. So Kemp thought he had proved the "four-color problem", but later people discovered that he was wrong.

In 1922 Franklin proved that every map with up to 25 countries can be colored with four colors. In 1926 Reynolds extended this result to 27 countries, and then in 1938 Franklin created Records of 31 countries. After Winn proved the situation for 35 countries in 1940, research in this area stagnated. It was not until 1970 that Orr and Stempel proved the four-color pattern for all maps containing up to 40 countries. Theorem. This number reached 96 before Haken and Appel finally eclipsed all such results by proving the four-color theorem.

In 1950, the German mathematician Schish estimated that proving the four-color conjecture would involve about 10,000 different configurations. Although his estimate later proved to be an exaggeration, it correctly pointed out that the four-color problem may only be solved with the help of This problem can only be solved by powerful computing devices that can handle huge amounts of data.

In 1972, Haken and Appel teamed up. After four full years of intense work, in June 1976, they spent 1,200 computer hours using three computers and processed more than 2,000 configurations before verifying the four configurations.

The color problem is established, but it is definitely not satisfactory to mathematicians.

——————

Wu Zhe first started with the problem of coloring determination: assuming that a graph g is known and only m colors are allowed to be used to color the nodes of g, can any two adjacent nodes in the graph have different colors?

Woolen cloth?

From the m-coloring optimization problem, we find the smallest integer m that can color the graph g. This integer is called the color number of the graph g. This is the minimum coloring problem of the graph to find the value of m.

for(i = 1m= n; i++)

a＾r/(a-b)(a-c)+b＾r/(b-c)(b-a)+c＾r/(c-a)(c-b)

When r=0,1, the value of the formula is 0; when r=2, the value is 1; when r=3, the value is a+b+c

…

V+F-E=X§, V is the number of vertices of the polyhedron P, F is the number of faces of the polyhedron P, E is the number of edges of the polyhedron P, and X§ is the Euler characteristic number of the polyhedron P.

If P can be homeomorphic to a surface (which can be commonly understood as being able to inflate and stretch on a spherical surface), then X§=2. If P can be homeomorphic to a surface connected to h ring handles, then X§=

2-2h.

...e-ix=x, and then use the method of addition and subtraction of the two equations to get: sinx=(eix-e-ix)/(2i), cosx=(eix+e-ix)/2.

If x in eix=x is taken as ∏, we get: e^i∏+1=0.
Chapter completed!