Wu Zihan looked embarrassed: "Brother Jie, I will have an Olympiad class later, or I will help you make an appointment with your brothers, and I will have to ask for a leave of absence." ”

Lan Jie asked, "You also applied for CMO, right?"

"Well, I did. ”

"CMO starts next week, Zihan, you are still going to the Olympiad class for intensive training, it seems that you attach great importance to it. ”

"It's not okay if you don't pay attention to it, we're already in our third year of high school, so get an offer early and get out early. ”

"Okay, let's not have dinner together, go back to our own homes. ”

During this special period, the brothers could not send their cars, so Lan Jie returned home to study mathematics and prepare for the preliminary CMO competition.

The days of waiting for the CPhO score are difficult, Lan Jie waited and waited, and waited until the evening of September 12, the Dayue Provincial Physics Association released a message on the official website: "The qualification line for this year's CPhO Dayue Provincial Semi-final is 112 points (top 30%), and the scoring of the preliminary round has ended, and all participating students can check the preliminary results on the official website." ”

It's out, it's finally out.

Lan Jie's hand trembled slightly, and he entered the admission ticket number on the official website.

"Come on 112, I must be taller than you!"

Inquire!

Score!

A line of words flashed out of the screen: Lan Jie, 198 points.

"Yay!

"Who deducted two points for me?"

"Buckle it, just buckle it, I'm promoted anyway!"

Lan Jie made a historic breakthrough, and he ate this dinner with tears in his eyes.

"198 points, that's pretty high. Lan Jinhui expressed satisfaction.

Lan Jie wiped away his tears: "I'm sorry, I'm so excited, to tell you the truth, this preliminary round of physical competition is quite simple for me, I should keep a normal heart." The day after tomorrow will be the CMO, and I hope that the CMO will also make it to the semi-finals. ”

Lan Jinhui asked, "In terms of mathematics, what do you need me to help you do?"

"It's mostly algebra, Dad, and I'd like to hear your algebra lessons. ”

"Come on, class. ”

The son put forward his learning needs, and the father of course spared no effort to guide his son.

"Applejack, you've mastered the carry system, right?"

"The carry system is very easy to understand, and every k enters 1. Binary, ternary, occimal, thirty, k, the basic principles are the same. ”

"What is the binary of 1988?"

This simple, 1988 equals parentheses 11111000100 inverted parentheses 2. It is an 11-bit binary number. ”

"Again, how many binary palindromic numbers are there in a positive integer that does not exceed 1988?"

"Wait a minute, I'll do the math. I worked out that out of a positive integer that did not exceed 1988, there were 92 binary palindrome numbers. ”

"What about those over 1988?"

"There are only two binary palindrome numbers of 11 bits that are more than 1988, and they are (11111011111)2 and (11111111111)2. ”

"The carry system is a tool, Ajay, you can use the tool proficiently, so I will focus on the number of palindromes for you. We have done calculations with supercomputing, adding any natural number to its inverse number, and then adding the sum and the inverse order of the sum, and so on, after a finite number of steps, we must finally get a palindrome number. ”

"Hey, it's math, the most theoretical kind of math. Dad, you're studying this thing?"

"The more you study physics, the more important you will find in mathematics. Let's move on to palindrome numbers, Applejack, we use supercalculations to get the phenomenon, do you understand? I ask you to use mathematical methods to summarize mathematical laws to explain the phenomenon of palindromes. You can think of it as a math proof problem, and I'm betting on it. ”

"This ...... How can you prove this? Can Dad give me some hints?"

"Applejack, you think for an hour, and after an hour, I'll give you a hint. ”

Lan Jinhui seems to be very fond of palindromes, and he only bets on the type of question that only bets on palindromes.

Under the guidance of his father, Lan Jie studied the relevant knowledge of palindrome in depth.

As he learned, Lan Jie discovered that palindrome numbers were easy and difficult, the lower limit of palindrome numbers was ordinary middle school math problems, and the upper limit was a super problem that stumped all mathematicians.

After a night of silence, on the morning of September 13, Ranger came to the sheep.

The first session is Tang Xiaoyun's physics class, probably because she bet on the right topic of the preliminary competition, and she is in a good mood: "Congratulations to Lan Jie, Wu Zihan, Li Zihan, Chen Zixuan, Huang Zihao...... I am very happy that 10 students will advance to the CPhO semi-finals, and our class will have the largest number of promotions. The ten students who read their names, you don't have to attend classes in the third and third class classrooms recently, you go directly to the competition classroom to report to Teacher Tong Yuanhong, go now. ”

Ten students strode out of the third and third class classrooms and went to the competition classroom on the top floor of the teaching building.

Tang Xiaoyun said to the students who stayed in the classroom: "You can prepare for the college entrance examination with peace of mind, from now until next year's college entrance examination, I will only talk about the knowledge related to physics in the college entrance examination." Next, let's revisit Newton's laws of motion......"

Lan Jie and the other ten people walked upstairs, everyone laughed and laughed, and the experience of promotion made them feel that they were strong.

Not all students signed up for CPhO, and only 30% of those who did advanced to the semi-finals. They are indeed strong.

"I heard that the proportion of the provincial prize is 30% multiplied by 10%, which means that only one of our ten people can go to the national competition. After laughing, Wu Zihan's face was solemn.

If one out of ten people is selected to go to the national competition, it must be Brother Jie!

If you can't win the national award, it's useless!

Chen Zixuan said: "Zihan, it's not you who counts it like this. The base of the calculation is not our third and third classes, but all the semi-finalists in the province. To put it bluntly, we have to compete for a place in the national competition with other high school players. ”

"Yes, yes, there is no enemy among the sheep!" Wu Zihan would of course calculate such a simple math problem, and after the calculation, he was happy again.

"The advantage of our sheep competition team is that we have the gold medal coach Tong Yuanhong!"

"That's right, Teacher Tong has cultivated an IPhO gold medal player like Senior Sister Yuan Zhi, and Teacher Tong will definitely train us to be a gold medal player!"

"Anyway, Mr. Tang's state of betting is hot, should Mr. Tang be transferred to the competition team?"

"Teacher Tang is gone, what should I do with the third and third classes?"

Everyone talked about it, and in a blink of an eye, they arrived at the door of the competition classroom.

Lan Jie instructed: "Brothers, don't discuss the teacher's arrangement, this kind of thing is for the school leaders to consider." After entering the competition classroom, everyone should pay attention to their remarks, and don't embarrass us for the third and third classes to avoid unnecessary controversy. ”

"Roger!"

"Understood!"

"Let's go inside!"

Lan Jie led the nine students in the class into the competition classroom, where Ms. Tong Yuanhong and her assistant were already waiting.

Lan Jie, the eldest brother who took the lead, said majestically: "Teacher Tong, a total of ten students from our third and third classes have advanced to the CPhO provincial semi-finals, report to you!"

Tong Yuanhong smiled with relief: "Lan Jie, you are finally here, you did not disappoint me." You and your classmates, find a seat to sit down. ”