Soviet Godfather

The second day of the game will start at 9 o'clock in the morning and last until 1:30 in the afternoon, for a total of four and a half hours. ??www?w?w?. In yesterday's game, Grigory, who was in great shape, attracted everyone's attention as soon as he entered the field. Sergei is still sitting in the audience, and he is very much looking forward to the Soviet delegation's victory in today's game. The deputy leader professor who was sitting next to him yesterday was still sitting with Sergey. With him in Seleosa, he can still understand some things in the game.

　　 After the start of the competition, Xie Liaosha also got the exam questions. Now he has completely given up on his math level, but he is more and more interested in this competition. Xie Liaosha feels that if he has a child in the future, he must be encouraged to study mathematics, not to mention, at least he can have a great advantage when playing poker.

Almost all the viewers around were immersed in the calculations. Sergey was too embarrassed to find someone to chat, because it might affect others, so Sergey picked up the test paper that was thrown aside, picked up paper and pen, just like other people. Start trying to solve the problem like that. Yesterday, the deputy team leader told Xie Liaosha that the first question in the game is generally the simplest, and the more difficult it becomes as you go back. Therefore, Xie Liaosha does not expect to be able to do the following questions, and instead specializes in the first one.

This is a grouping question. The question narrates that a company needs to arrange work for personnel, but due to some special reasons, some of them cannot be grouped together for some reasons. The question finally requires the contestants to design an algorithm Not only can these special situations be properly handled, but also the minimum number of departments should be used to make the personnel get reasonable arrangements.

　　 Xie Liaosha thought for a while, but he didn't have a clue, so he didn't intend to continue wasting time here. He went outside, took out a cigarette, put it on his mouth, and lit the cigarette. Sergey checked the time, it was almost an hour. Suddenly there was a stir in the factory. Sergey thought that Grigory must have handed in the paper ahead of time, so he extinguished half of his cigarettes, turned around and returned to the arena, intending to see this magical guy again. How to kill the Quartet.

　　 Xie Liaosha returned to his seat, said hello to the deputy leader professor, and then asked, "How about it, did Grigory hand in the paper again in advance?"

　　 "No! It's an American this time!" The deputy leader professor said disappointedly. Sergei quickly looked at the scoreboard, and sure enough, there was still a big 0 underneath, and a big 35 had appeared under USA.

　　 Xie Liaosha felt a little unexpected, so he asked the deputy leader professor next to him: "What's the matter? Is today's topic particularly difficult?"

"The other questions are very simple. Only the last one is very difficult. The contestant who turned in the first paper just now lost points because of the last one. He thought he had made this question, but was pointed out by the judges. Fatal mistake..." The deputy leader professor explained to Xie Liosa what had just happened.

　　 As long as someone talks to him, Sergei will not feel that the time is long. The deputy team leader also put the test papers aside, and the two began to pay close attention to the movement on the field. As time went on, more and more players began to hand in papers, but they never showed a full score. Sergei looked at Grigory in the audience. Grigory was holding messy hair in both hands, and he was almost sticking to the test paper. Could it be that he was also stumped by the last question? Sergei couldn't help but doubt.

　　 Three hours have passed, more and more students are beginning to hand in their papers, and the scores on the scoreboard have begun to change, but so far there is no full score. USA and the scores are still very close, but this time the American leads. Sergei looked at Grigory, who was still sitting still in his seat, and it seemed that he was caught in a hard fight. Three and a half hours later, the members of the US and Federal Republic of Germany teams have all turned their papers, and only two Soviet students are left in the field, one of which is Grigory. The scoreboard showed that the US team had the highest score, followed by the Federal Republic of Germany, and finally the Soviet Union. However, since two Soviet students have not yet turned in their papers, it is not yet known who will die.

After a while, a Soviet student turned in his paper, and only Grigory was left in the audience and continued to do the questions. There is no full score today. It must be said that it is a pity, so everyone put their hope on Gerry On Gory's body, the mathematicians in the audience were also eagerly looking forward to when Grigory would turn in the paper. The time came to 1:30 in the afternoon. When the game time was over, the referee in the field walked to Grigory's side, watching how he solved the problem, and suddenly there was a surprised expression on his face. The U.S. representative quickly protested because the game was over and no one should be taken care of.

　　 The referee nodded and took the test paper from the side of the table. It turned out that Grigory had already put the test paper aside. But Grigory did not get up, still calculating something. The referee on the court did not agree with the American team’s accusation that Grigory was overtime. Grigory’s test paper had long been put aside. He was not busy with the problem on the test paper, and no one knew what he was doing now. .

　　 No one stepped forward to disturb him, and Grigory was still doing his calculations with no one else. Soon the referee announced Grigory's score, 35 points, which means that Grigory did not make a question. The total score of the Soviet delegation can only get second place.

　　 "Is it the last question?" The deputy team leader asked hurriedly.

　　 "No, he is the only player who has done the last question!" The referee shook his head regretfully, and then said.

　　 "That question?" The deputy team leader asked in a puzzled way. He couldn't think of the last question on the paper and what else could be difficult for Grigory.

　　 "It's the first question!" The referee's answer surprised everyone. Everyone looked at each other, and no one could guess why it was the first question.

　　 Xie Liaosha pulled the deputy leader professor who was stunned on the spot aside, and asked curiously: "What's wrong with the first question? Haven't many people done it?"

The deputy team leader also replied with a confused look: "Yes~www.wuxiaspot.com~ I don’t understand why this is? The first question uses the knowledge of the four-color conjecture. As long as the children can compete here, It should be done."

　　 "Four-color conjecture? Is it the one that marks all countries in four colors on the map?" Sergey asked hurriedly.

　　 "Oh! I see! Could it be that Grigory wants to prove the four-color conjecture?" The deputy leader professor said suddenly. Before Xie Liaosha asked, the deputy leader professor started to explain like Xie Liaosha, a layman.

"The four-color conjecture is one of the three largest mathematical conjectures in the world. Since it was proposed in 1852, it has been plagued by mathematicians all over the world. However, five years ago, in 1976, Americans made 10 billion This conjecture was finally violently cracked, so Americans thought it could be called the four-color theorem. However, until now, mainstream mathematics still has reservations about this result, because it is always obtained in a finite set. The conclusion. But this conjecture seems simple, but how many geniuses have tried to prove it, but ultimately failed." The deputy team leader explained to Xie Liaosha in detail.

　　 "In other words, only by acknowledging the results of the Americans can the first question be solved, right?" Sergey asked. The deputy leader professor nodded regretfully. (To be continued.)