Coming out of the library, Chen Zhou and Yang Yiyi walked on the way back to the dormitory.

When the two of them walked to the nameless lake, they both stopped unconsciously.

Under the illumination of the lights, the nameless lake has a unique view.

Chen Zhou turned his head to look at Yang Yiyi, and said softly, "Yiyi, let's walk along the nameless lake, shall we?"

Yang Yiyi nodded: "Okay." ”

Chen Zhou took Yang Yiyi's hand, and the two of them walked quietly on the shore of the nameless lake.

Objectively speaking, Yan University is not only one of the top universities in China, but also one of the most beautiful universities in China.

After all, there are quite a few quaint buildings on the Yan University campus, and they also have a certain historical significance.

Take Yan Garden as an example, it was the spoon garden of the Ming Dynasty at the earliest, and later the royal garden of the Qing Dynasty.

It is now the campus of Yan University.

And the most famous of Yan University is the nameless lake where Chen Zhou and the others are wandering at the moment.

It is known as "Yita Lake Map" together with Yabota and Yanda Library.

If you wait until the lotus flowers are in full bloom, the whole nameless lake is full of fragrance.

In addition, the Yabo Tower on the shore towers into the clouds and stands majestically, as if guarding the landscape.

The movement of the nameless lake, with the stillness of the Yabo Tower, the lake is moving and the tower is quiet, the lake is soft and the tower is strong, and the tower and the lake complement each other.

Chen Zhou pointed to the Yabota in the distance and asked softly, "Yiyi, do you know what this Yabota used to do?"

Yang Yiyi glanced at the Yabo Tower, which imitated the ancient tower of the lamp, and said with a smile: "Of course I know, it was originally used as a water supply tower. ”

Chen Zhou nodded lightly and asked again, "Then do you know the meaning of Yabota and Nameless Lake?"

Yang Yiyi thought for a while and replied: "Yabota means boya, and if there is no nameless lake, I don't know." ”

Chen Zhou stopped, looked at Yabota in the distance, and said slowly: "Yabota seeks boya in front of Yabota, and vows to be famous on the shores of the nameless lake." Their moral is to swear in the Nameless Lake to become a liberal arts person. ”

Yang Yiyi looked at Chen Zhou with a smile: "Okay, okay, I know that you are a linguistic tyrant." ”

"Hey, hey. Chen Zhou smiled embarrassedly.

Yang Yiyi glanced at Chen Zhou and asked softly, "Do you have something on your mind?"

Chen Zhou shook his head and nodded again, but did not speak.

Seeing this, Yang Yiyi said softly: "The matter of the subject?"

"Hmm. Chen Zhou nodded, "In today's small class, Professor Zhang taught a math game, which can be regarded as an enlightening lesson." ”

Yang Yiyi asked, "What game?"

Chen Zhou: "Hail conjecture. ”

As smart as Yang Yiyi, she naturally understood what Chen Zhou meant.

She thought for a moment and said, "It's really difficult to study this as a subject. But why hesitate when you've already decided?"

Chen Zhou turned his head to look at Yang Yiyi, he was indeed hesitant.

Although the decision was made to study the hail conjecture, he also set a deadline for himself.

However, he is still a little worried about this kind of world-wide problem.

I'm most afraid of spending time and getting nothing.

Chen Zhou said frankly: "I don't know if I can complete this project. ”

Yang Yiyi clasped Chen Zhou's hand with her backhand and said softly: "If you hesitate like this, it's not like you." The person who dares to make a 725 agreement with all the teachers and students of the school, and dares to plan to complete the double graduation of the Department of Mathematics and the Department of Physics in his freshman year, should be a person who will not hesitate to encounter anything. ”

"We don't know what the future holds, but we can take every step of the way today for the future. And what the result of this project will be known only after it has been done. ”

"Most importantly, I trust your decision. ”

This is the first time Chen Zhou has heard Yang Yiyi say so much, and what he saw from Yang Yiyi's eyes was complete belief.

Chen Zhou smiled lightly and rubbed Yang Yiyi's head with his other hand: "You're right, you should have done it to know." Instead of hesitating after having already decided. ”

"That's right. Yang Yiyi said with a smile, "It's not like you just said, Yabota asks for boya in front of Yabota, and vows to be famous by the nameless lakeside, don't we just ......?"

Before Yang Yiyi finished speaking, Chen Zhou suddenly had a force on his hand and pulled her into his arms.

He hugged it tightly.

Her hands also changed from panic at the beginning, to slowly resting on his body.

Chen Zhou whispered softly in Yang Yiyi's ear: "Thank you, Yiyi, it's good to have you." ”

Although Yang Yiyi didn't speak, the corners of her mouth unconsciously showed a smile.

After a long time, the two separated.

Chen Zhou looked at Yang Yiyi's red little face, and couldn't help but quip: "Are you a red apple?"

"Hmph. Yang Yiyi snorted, "You are the red apple." ”

When Chen Zhou returned to the dormitory, it was almost 11 o'clock, and it was much later than usual when he came back from the library.

As soon as they entered the dormitory, Zhao Qiqi and the three of them looked at Chen Zhou together.

Chen Zhou asked suspiciously, "Why are you looking at me like this?"

The three of them said in unison, "It's nothing, I thought you wouldn't be back tonight." ”

Chen Zhou was slightly embarrassed: "If I don't come back, where will I sleep?"

Zhao Qiqi said: "Then I don't know. ”

After a pause, Zhao Qiqi keenly found something, and then said softly: "You have the smell of her perfume on your body, it is my nose that has committed a crime......

Chen Zhou: "......"

Zhu Mingli and Li Li snickered on the side.

Ignoring the three of them, Chen Zhou picked up the basin and went to wash.

"......"

When washing, Chen Zhou realized why these three people looked at him like this.

When he hugged Yang Yiyi, Yang Yiyi's hair fell on his clothes.

It's still a very conspicuous location......

At night, Chen Zhou, who was lying on the bed, remembered Yang Yiyi's words, and the corners of his mouth unconsciously had a hint of a smile.

Chen Zhou's heart has also become more eager to solve the problem of hail conjecture.

sent a [good night] to Yang Yiyi, and Chen Zhou fell asleep.

In the next few days, Chen Zhou studied the textbooks of the physics department according to the plan.

On the one hand, a lot of time is spent looking up topics related to the hail conjecture.

There was a surprising discovery for him, that is, the algebra discussion class about Zhang Zhongyuan.

Some of the content discussed in class was recorded in the problem set.

This also verifies from the side that the content discussed in that lesson is flawed.

And those that were not recorded also provided Chen Zhou with some references for the subject.

"Formulating a problem is what must be done to solve a conjecture. Regarding the hail conjecture, or the 3X+1 conjecture, his formula is an iterative formula, with inputs, outputs, and feedback......"

Chen Zhou first formulated the hail conjecture and then studied it.

[Xn+1=(3Xn+1)/2^m, where each X is an odd number, m=1,2,3......]

[Until the even number 2^m in 3X+1 is precipitated and canceled out so that the right side of the equation is an odd number.] If this odd number is not 1, but some other odd number, continue to iterate until 1. 】

[In other words, what needs to be proved is (3Xn+1)/2^m=1]