"Why are you here? It's cold, come on in and talk." Hua Luogeng looked surprised when he saw Yu Hua with his head covered with snowflakes, and motioned for Yu Hua to go inside first.
Yu Hua nodded and followed Hua Luogeng into the house.
"Squeak!" There was a slight rubbing sound from the door, and it closed shut. As soon as you entered the room, a feeling of warmth suddenly came to you.
"It's so late, it must be very cold on the road." Hua Luogeng took off his coat and hung it on the hanger, exhaled a white breath, glanced at Yu Hua, who was covered with snow and frost on his body and head, took a step forward, reached out and patted it away gently
The snow and frost on Yu Hua’s shoulders.
Yu Hua smiled: "Students are not cold..."
"Luo Geng, who is here again?" At this time, a gentle voice came from the bedroom, and Wu Xiaoyuan, wearing a winter coat, came out.
"Xiao Yuan, this is a student I met before. I want to talk to him about something. You go and cook a bowl of ginger soup to warm him up." After hearing this, Hua Luogeng's eyes were full of softness and he looked towards Wu Xiaoyuan.
Smiled.
"Hello, Madam, my student's surname is Yu, and his name only has a Chinese character. I'm really sorry for bothering me in the evening." Yu Hua stood aside, bowed to Wu Xiaoyuan, and apologized.
When Wu Xiaoyuan saw Yu Hua being polite and courteous, he felt good about him and said with a smile: "Why are you nagging me? You go to the study and I will make ginger soup for you."
"Thank you, Master." Yu Hua quickly thanked her.
"Yu Hua, come to the study to talk." Hua Luogeng smiled, straightened his sweater, motioned for Yu Hua to follow, and then walked to the study.
Yu Hua nodded, followed Yu Hua Luogeng into the study, and gently closed the door.
"Sit down, why did you come to me today? Didn't I say before that you should not be disturbed except when borrowing books for reading or when your life is in danger?" Hua Luogeng walked to the desk and sat down, taking out a pack of cigarettes from his pocket.
He took out one and lit one, motioned Yu Hua to sit down, and asked.
"The students are here because they want to borrow books and read. This is the report card of the student's first month's quiz." Yu Hua looked solemn and did not sit down. He took out the report card from his inner pocket and handed it to Hua Luogeng.
.
Hua Luogeng took a puff of his cigarette. Hearing this, he became curious. He reached out and took the transcript and took a look at it. He couldn't help but be startled: "Is this your score?"
"Yes." Yu Hua nodded seriously.
"I've known you before. Didn't you score 594 last semester? Why did it suddenly increase so much?" Hua Luogeng put down his transcript. He had clearly remembered a series of numbers. He was a little confused, but he did not suspect Yu Hua of cheating.
Because he was the one who wrote the math test paper for this small test in Peiping No. 4 Middle School.
698 points, only 2 points away from the perfect score. Hua Luogeng had specially read Yu Hua’s student file and knew that Yu Hua’s score at the end of last semester was 594.
Between 698 and 594, the difference is a full 104 points.
"The students suddenly felt enlightened. The knowledge in the books was simple and easy to understand, and they could be remembered quickly." Yu Hua said seriously.
Hua Luogeng nodded and suddenly said: "How fast can it be?"
"Uh... you can basically remember it just by looking at it." Yu Hua was startled for a moment, not expecting Hua Luogeng to ask such a question. He was silent for a few seconds and then responded.
"Oh? Then take a look at this set of numbers." Hua Luogeng's eyes lit up. He put down the burning cigarette in his right hand, took out the pencil from the table, quickly wrote out two hundred numbers, then tore off the draft paper and handed it to Yu Hua.
Yu Hua stepped forward and took the scratch paper. He looked at this group of numbers and felt very familiar. After browsing it, he put it back on the desktop: "The student has written it down."
"Come back and listen." Hua Luogeng held a cigarette between his fingers and said with a smile.
"89793, 23846, 26433, 83279..." Yu Hua's face was natural, and the whole set of numbers recorded in his mind was extremely clear, neither fast nor slow. Using five numbers as the dividing line, he slowly recited two hundred numbers without any rules.
number.
Hua Luogeng did not lower his head to look at the draft paper. Those numbers had already been memorized in his mind. All his eyes fell on Yu Hua in front of him, with a smile on his face and nodding in recognition from time to time.
After tens of seconds, the recitation sound in the study disappeared.
Yu Hua said respectfully: "Sir, the students have finished memorizing the 11th to 210th digits of pi."
Along with the recitation process, Yu Hua has understood that the two hundred numbers he memorized are from the tenth to the two hundred and tenth digit of pi.
"I didn't expect you to know that this is the 210th digit of pi. Yu Hua, can you memorize the 1,000th digit?" Hua Luogeng asked with a hint of appreciation in his eyes.
When Yu Hua heard this, he looked astonished: "Sir, have you calculated pi to the 1,000th place?"
Memorizing the digit to the 1000th digit is not a problem. What is difficult is manually calculating pi to the 1000th digit.
As one of the mathematical constants, pi has always had an unparalleled unique charm in the mathematical world. Mathematicians around the world are proud of deducing pi.
The historical development of pi is very interesting, divided into three stages, from its birth to the geometric method, and then to the current analytical method period.
At the beginning of its birth, the value of pi was only 3.139 with three decimal places. In the period of the Geometry Law, the record of seven decimal places maintained by Zu Chongzhi for nearly a thousand years was born. A thousand years later, the Arab mathematician Qasi obtained the precise value of pi with 17 decimal places.
, German mathematician Rudolf van Coylen calculated to 20 decimal places and the 35th digit.
During the analytical period of the 18th century, the decimal value of pi finally made a historic breakthrough and reached the 100th place through infinite series.
From the 18th century to today, the latest published digit of pi is the 268th.
It can be said that every additional digit in the decimal value of pi represents an advancement in mathematics.
But what did he hear now?
Hua Luogeng has calculated pi to the 1,000th place, and quietly broke the current world pi record.
Is this the power of the father of Chinese mathematics?
"I have nothing to do, and I have reached the 1095th place." Hua Luogeng smiled.
What a great time to have nothing to do...
You are willful.
Yu Hua took a deep breath: "Students can memorize it at a glance."
"Here are the thousand digits at the back for you." Hua Luogeng took out a stack of scratch paper full of notes from the drawer. Without thinking, he took out a scratch paper full of numbers and handed it to Yu Hua.
Yu Hua's face was natural and without any pressure. He took the piece of scratch paper that condensed the wisdom of Hua Luogeng and read it carefully as usual. After ten seconds, he wrote down the 210th to 1000th digits and then put down the piece of paper: "
4428810975…”
Seven hundred and ninety is too many numbers, so just memorize them in groups of ten.
Yu Hua's reciting speed was neither too fast nor too slow. According to his own rhythm, Hua Luogeng closed his eyes and listened carefully, with a slightly serious look on his face, but did not rush.
Memorizing a thousand digits of pi isn't too difficult with his memory, but it requires concentration.
A few minutes later, the sound of reciting in the study disappeared again.
"Sir, the student has finished reciting." After reciting, Yu Hua said softly.
Hua Luogeng slowly opened his eyes. The cigarette in his hand had burned out. He put it in the ashtray, took out another one, and lit it with a match: "In other words, you have completely mastered all the knowledge points of arithmetic and other science subjects in high school.
Yeah?"
"Yes." Yu Hua nodded.
Hua Luogeng looked at Yu Hua: "Have you got the quota of recommended students from National Tsinghua University in your fourth middle school?"
"I got it. Students will write the application form when they are ready to go back." Yu Hua nodded.
The room fell into silence.
Hua Luogeng didn't speak anymore, smoking a cigarette and seemed to be thinking about something. Yu Hua stood in front of the desk, meticulous, quietly waiting for Hua Luogeng's attitude.
"Dong dong!" At this time, the door suddenly knocked.
"Please come in."
The door opened, and Wu Xiaoyuan walked in with a food tray with a bowl of steaming ginger soup on it. He came to the table and put it down, showing a gentle smile to Yu Hua: "Here comes the ginger soup. Drink it while it's hot.
To get rid of the cold, Luo Geng, smoke less."
Hua Luogeng nodded with a smile, but it didn't go out.
"Thank you, Master." Yu Hua thanked her softly.
Wu Xiaoyuan waved his hand: "You're welcome, you can continue chatting."
The words fell and he left.
The door was closed again, and the study fell into silence again.
The second cigarette burned slowly, emitting wisps of smoke.
"Yu Hua, why are you studying mathematics?" After a long time, as the second cigarette in his hand burned out, Hua Luogeng seemed to have made some decision. He raised his head, his eyes shining with light.
The reason for hesitating for so long was not that he didn't want to teach Yu Hua, but... Yu Hua's growth rate and talent were so fast that it was scary.
A student who is within the expected range and a genius whose growth rate and talent are completely unpredictable are two completely different concepts.
Hua Luogeng, who stands at the forefront of the entire Chinese scientific research field, and even Yu Hua can memorize the performance of 1000th digit pi at a glance, what does it mean.
Hua Luogeng knew how valuable the mathematical knowledge in his head was. This was an important weapon and should not be taught lightly.
"Mathematics is a tool of natural science, and students want to get the sharpest tool." Yu Hua responded sternly without changing his original intention.
"We are facing a national crisis and the country's current atmosphere and environment make it impossible to conduct any scientific research. You have no funds, you have no supplies, you have no resources. All the science and technology you study will be swallowed up, leaked by the government, and even subsidized by the enemy.
, if the Japanese obtain any advanced technology, the threat to the country and nation will be even greater."
Hua Luogeng spoke solemnly: "Science is a double-edged sword."
He didn't know what kind of scientific research Yu Hua wanted to engage in, but he knew that if Yu Hua, who was extremely talented and potential, didn't do it, it would be earth-shattering if he did.
Mathematics is a tool of natural science. If you can realize the true meaning of this sentence, Yu Hua's vision and wisdom have surpassed 99% of middle school students and technical talents.
Because mathematics is the only tool to know what is happening and why.
"Sir, if you reject scientific research and progress just because of potential threats, I think people with this kind of thinking are ridiculous and have no future. If this kind of thinking becomes popular in a country, then it will surely perish!"
Yu Hua looked solemn and serious and responded: "Of course, students are not talking about you. You can find funds, materials and equipment. Students believe that there are always more solutions than difficulties."
funds?
Earn it yourself, borrow money from classmates, or even borrow money from poor people!
Materials are the same as above,
The equipment is the same as above.
There are always more ways than difficulties. If it is so-called difficulty, then deny everything. If scientific research and progress are rejected because of potential threats, then this kind of thinking is really ridiculous.
Superficial and one-sided people will only see superficial things and only see what they want to see. Whenever things are different from themselves, they will only criticize and deny them, and even bark like a lost dog.
.
If this kind of thinking prevails in a country, it will surely perish. Of course, there is one more thing Yu Hua did not say, that is, the National Government has fully demonstrated the characteristics of failure and destruction in the future.