Escape From the Library

The course "Prime Number Labyrinth" of the School of Mathematics allowed the four members of the research team to get as high as 585 points, which is higher than the previous "Cardiovascular Ward" points, and they only spent an hour and a half for so many points!

Recalling the 5-day thrilling experience of finding the murderer and fighting monsters in "Cardiovascular Ward", this time it took 585 points in an hour and a half, which was really easy.

Yue Xingwen was excited, turned around and gave Jiang Pingce a hug: "Full score, you are awesome! The three of us just ran errands, and we can get 585 points, so comfortable!"

Liu Zhaoqing said with emotion: "This should be the easiest time for us to get points, right? There is a top student in the team, it's like cheating."

Ke Shaobin also said seriously: "Even if I take a calculator, I guess it can't compare to Pince's mental arithmetic speed."

Yue Xingwen has always known that Jiang Pingce is good at mathematics. In high school, Jiang Pingce got full marks in every exam in mathematics. It is said that the mathematics teacher in his class would directly use Jiang Pingce's papers as standard answers to give questions.

In college, Jiang Pingce became even more powerful. This time the maze combined mathematical operations and three-dimensional geometry analysis. Without Jiang Pingce, they might not be able to find their way out in 1 hours, let alone one and a half hours.

Yue Xingwen patted Jiang Pingce's shoulder lightly, and said with a smile, "Great hero, thank you for your hard work this time."

Jiang Pingce said: "It's okay, no hard work."

After the first course, the time in the library was ten o'clock in the morning. Yue Xingwen glanced at the clock on the wall and said, "Let's go back to the dormitory first. Brother Zhuo Feng and the others are going to retake the courses of the medical school. It should be soon." Out."

When the four of them went out, they returned to the hall of the School of Mathematics. Many students gathered under the big screen of the schedule. All the students were frowning, obviously not knowing how to pass the school of Mathematics.

Yue Xingwen glanced at the students who were at a loss, lowered his head and thought for a while, leaned into Jiang Pingce's ear, and said softly: "The failure rate of the course "Prime Number Labyrinth" in the School of Mathematics is as high as 65%. It stumped many students. If you don’t mind, how about sharing our customs clearance strategy with everyone and helping them?”

Jiang Pingce simply agreed: "Okay, I'll go back and sort out my thoughts."

They have already finished the exam, and sharing strategies to the students behind them will not have any impact on their own results, just like many senior students in the university will share their experiences and provide review materials to junior juniors and juniors.

Yue Xingwen has received help from many brothers and sisters at school, and he himself often shares information on forums.

Jiang Pingce has never done this.But now, the library is different from the reality. If you fail a course, you will have to rebuild it, and if you fail a course again, you will die!Since Yue Xingwen called for the establishment of a university alliance, Jiang Pingce is of course willing to cooperate with him and share his experience so that the students in the future can pass the test more easily.

When the two returned to the dormitory, Jiang Pingce began to organize the map of the maze.

He redraws the map of the upper, middle and lower floors, takes pictures and uploads them with the tablet computer that comes with the dormitory, and then posts a post on the forum——

[Guidelines for clearing the course "Prime Number Maze" of the School of Mathematics]

Jiang Pingce's strategy post is very concise, using the black Song typeface that comes with the forum.As if doing a math problem, he simply listed a few key points.

60. Teams who don’t want to do additional questions and only want [-] points to pass the test:

The prime number maze is a three-layer three-dimensional structure. After entering the maze, you can ignore the numbers in all the rooms. You don’t need to calculate whether it is a prime number. You can simply use the numbers on the door as the number and draw the route while walking. You can walk in a straight line first. Step back from room to room, go right first, then left, find the elevator on this floor as quickly as possible, and go up/down.

The upper and lower floors of the maze are 7x7 rooms with a total of 49 rooms. Draw a total of 7 square grids with 7 horizontal and 49 vertical grids on the paper. Go straight to the end in any direction, turn right or left and continue until the end, that is, walk one "L"-shaped route, at this time, you will be in a corner of room 49, and then follow the "s"-shaped route to check, so that you will not take repeated paths and lose your way.

After finding the elevator, go out of the maze, the course is completed, and the score is 60.

Attached are the detailed three-story plan of the maze, the synthesized three-dimensional graphics, and the maze route map for reference.In the next exam, there may be some changes inside the maze, and the numbers will definitely change, but the overall structure and way of passing the level will remain the same.

[-]. Teams who want to do additional questions pass the level:

附加题要求收集所有孪生质数，因此需要搜索迷宫内的所有房间并且计算每一个数字是不是质数。尾数1/3/7/9是质数的可能性较大，尾数0/2/4/5/6/8直接排除。

1、快速判断一个数能否被3整除：将这个数的每一位数相加，若能被3整除则自身也能被3整除。例如数字185337，可直接计算1+8+5+3+3+7=27，27可被3整除，则185337也能被3整除，此数字不是质数。

2、快速判断一个数能否被7、11、13整除，可使用“末三法”，末三位与前几位的差值（取正数）能被7、11、13整除，这个数就能被7、11、13整除。

例：939911，可分割成939-911=28，28能被7整除，那么939911也能被7整除。

例；124371，可分割成371-124=247，247可被13整除，则自身也能被13整除。

Both the addition method and the last three methods are used to reduce the number of digits and simplify math-operations.

The proof is as follows:

Let a number be abcdef.

abcdef=abcx1000+def=abcx1001-abc+def=abcx7x13x11-(abc-def)

当abc-def能被7/11/13整除，则abcdef能被7/11/13整除……

Seeing this, Yue Xingwen gave up thinking about it with a headache, and slid through the content with his fingers.

Mathematics is indeed an amazing subject.

The strategies written by Jiang Pingce are serious and rigorous. They not only tell everyone what to do, but also tell everyone "why they should do this". Science students probably don't seem to have any difficulty, but liberal arts students are really dizzy.

After Jiang Pingce posted the strategy, the number of replies immediately skyrocketed.

Many juniors and sisters majoring in liberal arts left messages: "Xueba, my roommate asked me why I was kneeling to read your strategy!"

"How do I have the confidence to click into the strategy post of the School of Mathematics? I want to poke my eyes."

"My eyes tell me it understands, but my brain tells me: it doesn't understand!"

"What do you guys think, liberal arts students? You just need to pass the courses in the School of Mathematics. Can you just read the first one? This senior even drew a map, so the first one is quite easy to understand. As for the second one... I just skipped sorry."

"What you said above is correct, additional questions? Overthinking. Don't do additional questions, just ignore all the numbers, just go out of the maze and burn the incense!"

Many science students said that after reading the post, their thinking finally became clear, and they expressed their gratitude to Jiang Pingce who took the initiative to post the strategy, and many fans confessed to Jiang Pingce in the post.

In the replies, there are a lot of "senior brother is so handsome", "xueba" and "male god, do you still lack leg pendants".

Yue Xingwen couldn't help chuckling, looked back at Jiang Pingce, and joked: "Once you post this strategy, you will probably get a large number of fans in the library. I have seen dozens of replies to you confessing your love." one."

Jiang Pingce said lightly: "If you hadn't spoken, I wouldn't have written this strategy."

He has never been a warm-hearted person, but he never refuses Yue Xingwen's request.Whoever Xingwen asked him to help, he would help.If Yue Xingwen didn't say anything, he wouldn't waste his time actively posting strategy posts.

Yue Xingwen knew that Jiang Pingce had such a cold personality. Hearing this, he smiled and walked over to sit side by side with Jiang Pingce, and said: "Although some people can't understand your guide post, there are also a lot of students who can understand it." Learn from it, at least after understanding the first article, you can get out of the maze and get a passing score of 60."

He turned his head to look at Jiang Pingce, and said softly, "Pingce, writing this strategy is just a piece of cake for you, but it is like timely rain, which can solve the problems that many research groups cannot get through the prime number maze."

Yue Xingwen's expression was very serious: "Don't think that I am meddling and being kind. The environment in the library is too cruel. Just now, under the screen of the class schedule in the hall of the School of Mathematics, several girls were crying. It is easy for you The prime number maze may cause many students who are not good at mathematics to sleep well, or even be eliminated. We just help out, how many can help, what do you think?"

Every time he talks seriously to people, he can always convince them.

The corners of Jiang Pingce's lips raised slightly: "Well, listen to you. In the future courses, we can also sort out the exam strategy and give it to the juniors and younger sisters as a reference." He looked at Yue Xingwen beside him, his eyes gradually softened , "You have always liked helping others. With you in the library, the overall difficulty has been greatly reduced."

Whether it's formulating a student agreement to restrain everyone and prevent classmates from fighting each other; or actively posting strategies to give students more reference ideas for future exams...

What Yue Xingwen did has been helping his classmates.

It is he who makes the atmosphere of the whole library harmonious and warm.

The originally dark and thrilling escape game turned into a college final exam where "students work hard together".

From the replies on today's forum, it can be seen that many students responded with relaxed and humorous sentences, and some of them even dared to tease Jiang Pingce in their posts, just like chatting on school forums.Compared with the large-scale abuse and quarrels caused by the acid throwing the day before yesterday, the library forum is now gradually more energetic and warm.

Yue Xingwen was embarrassed by the praise, coughed lightly and said: "Don't put a high hat on me, I just do what I can, this time the maze is thanks to you. Now I understand what the map you drew is Meaning, it’s really powerful, if I analyze it myself, I can’t think of any 7x7 squares, and I’ve been dizzy for a long time.”

Jiang Pingce said softly: "My sense of space and calculation ability are indeed better than yours, but your language expression ability and knowledge are much better than mine. Everyone has their own strengths, so don't be ashamed because you can't compare with me in mathematics. "

Yue Xingwen raised his eyebrows: "How can I be ashamed? With you here, when I encounter mathematics in the future, I just give up thinking!"

The two smiled at each other.

On the forum, Jiang Pingce's post quickly became popular.

As Yue Xingwen said, this strategy post is just a timely rain in the scorching summer for the team trapped in the Mathematics Academy on the second floor.If you don’t do additional questions and just want to pass the maze according to Jiang Pingce’s method, even a team of four liberal arts students can pass the test with 2 points.Students with strong computing skills can try to do additional questions, and Jiang Pingce has listed many skills for them.

There are more and more thank you messages, and some younger brothers and sisters recognized Jiang Pingce's name and expressed their worship to Jiang Pingce, the legendary student of the Department of Mathematics.

Jiang Pingce glanced at the message and closed the forum.

This is the first time he has shared his experience with other students since he grew up.

In the three years of high school, because he was too indifferent, no one dared to ask him to borrow notes.When he arrived at the university, he walked alone, except for occasional self-study with Yue Xingwen, he rarely communicated with his classmates.

After the strategy post was posted, Jiang Pingce suddenly felt in a good mood when he saw a large number of "thank you" appearing in thousands of replies. The world can maintain kindness and innocence.

Such a person is the rarest.

Seeing Jiang Pingce looking at him all the time, Yue Xingwen couldn't help wondering: "What's the matter, am I wrong?"

Jiang Pingce smiled lightly: "You are right in everything you say."

Yue Xingwen patted the other person on the shoulder, with a proud expression of "you know what to do".After a pause, he said seriously: "Let's not go to the elective course this afternoon, shall we? I even have a headache looking at the schedule, so I'll pass the compulsory course first."

Jiang Pingce nodded: "Well, I will rest in the dormitory in the afternoon. Tomorrow at 8 o'clock in the morning, the School of Mathematical Sciences will have a compulsory course "Death Code". Let's go directly to this course."

Yue Xingwen was thoughtful: "Death code? The name sounds like a reasoning class?"

Jiang Pingce guessed: "It may be a suspenseful case related to numbers."

The two looked at each other, and Yue Xingwen smiled and said, "If it's a reasoning class, I can still help. At that time, let's complement each other in arts and sciences, pass the level together, and try to get more points to upgrade my dictionary!"