Cheng Che hadn't slept for three days, but after washing his face after dinner, he felt much better.
With the body's Enduring Progress Without Fail and Self-Healing Instinct working together, fatigue dissipates as quickly as if it were washed away by water.
He stood in front of the mirror, looking at his own face.
His eyes were still a little red, but he had regained his spirits.
He wiped his face and left the room.
"I'll take them out for a walk."
Cheng Jianguo and Jiang Xue exchanged a glance.
Cheng Jianguo was about to say something when Jiang Xue tugged at his sleeve.
Jiang Xue gave him a wink, meaning, "Let him handle his son's matter himself."
Cheng Jianguo swallowed the words he was about to say and waved his hand.
Cheng Qingshan sat in the courtyard smoking, watching his grandson lead the two girls out the door, and nodded with satisfaction.
"It seems the Cheng family is about to have many descendants."
Zhou Lan, who was picking vegetables nearby, nodded upon hearing this. "Both girls are good. One is a singer, and the other is from Beijing Normal University. They're both good."
Cheng Jianguo stood at the door, watching the three figures disappear into the path at the village entrance, and shook his head helplessly.
Mom and Dad, there aren't two... there are four!
Once outside the courtyard, Cheng Che took out his phone.
The screen was filled with messages and missed calls.
Yan Ruanning hit more than a dozen, Su Qingyue seven, and Su Miaoyin hit eight.
Guo Xin sent more than forty messages, while Zhou Mingxuan and Lin Xiao each sent about ten.
Qin Lie made three phone calls, and Chen Wei made two.
He replied to Guo Xin first, "My phone broke, I just got a new one. It's okay."
Then there's Zhou Mingxuan and Lin Xiao, for the same reason.
Next were Qin Lie and Chen Wei. He only said "the phone is broken," without mentioning a word about what he had guessed.
It's too complicated to explain, and now is not the time to talk about it.
Finally, he dialed Su Miaoyin's number.
I answered it after it rang once.
" Cheng Che!" Su Miaoyin's voice was clearly angry. "Why was your phone off? I called eight times! Do you know how worried I was?"
"My phone died back home," Cheng Che said. "I just plugged it in."
"Why didn't you top it up earlier?"
"Forgot."
Su Miaoyin snorted on the other end of the phone, but her anger had clearly subsided considerably.
Okay. What are you doing now?
Cheng Che thought for a moment.
Su Miaoyin is from Peking University, so she knows a bit about mathematics, and he has no reason to hide it from her.
"I did something," he said, "Mathematically."
"What's up?"
" The Integer-Coefficient Polynomial Root Distribution Conjectures has been proven."
There was a two-second silence on the other end of the phone.
Then came a scream.
"What?! You proved it?!"
Cheng Che moved his phone a little further away.
"Yes. Just finished."
" Cheng Che, that conjecture was proposed by Schinzel and Zassenhaus in 1965, and no one has been able to provide a complete proof for all these years. You did it all by yourself?"
"Um."
Su Miaoyin's voice was filled with undisguised excitement. " Cheng Che, you're amazing! I knew you could do it!"
Cheng Che smiled, feeling a warmth in his heart.
I believed without a doubt; only my parents used to do that.
Now there are a few more people.
I'll treat you to dinner later.
"You said it! You can't go back on your word!"
"No regrets."
He hung up the phone. As soon as he turned around, he met two pairs of eyes.
Yan Ruanning and Su Qingyue stood beside him, watching him.
Yan Ruanning's expression was gentle, but there was something in her eyes.
Su Qingyue's expression was calm, but the corners of her mouth were slightly pursed.
Both of their eyes were fixed on his face, as if trying to read the words from his face.
"Please reply to this message," Cheng Che said awkwardly, "Otherwise I'll feel bad."
Yan Ruanning was the first to look away, and nodded gently. "Mm."
The three people walked along the path at the village entrance toward the stream.
The countryside is quiet in winter, with large patches of withered grass and bare poplar trees on both sides of the road. In the distance, wisps of smoke rise from the rooftops of some houses.
Yan Ruanning walked to Cheng Che's left.
She suddenly pulled a handkerchief from her pocket and wiped Cheng Che's forehead with it.
"He's sweating."
She said the movements were very light, as if she were doing something very ordinary.
Cheng Che tilted his head slightly, but did not dodge.
Su Qingyue, who was walking on the right, slowed down a beat when she saw this scene.
Her gaze fell on the handkerchief, then on Yan Ruanning's hand, and then she looked away.
She felt uncomfortable.
She knew what Yan Ruanning was doing.
Cheng Che wasn't alone, but Yan Ruanning used this method to tell her: I arrived before you, I can do these things, what about you?
Su Qingyue clenched her hands in her pockets, her face burning with shyness.
She wanted to reach out, but she couldn't bring herself to do it.
There was something between her and Cheng Che, a thin layer, but one that couldn't be broken through.
She lowered her head, sulking.
The three people walked to the stream.
The stream was shallow and crystal clear, allowing you to see the pebbles at the bottom.
There is an old locust tree by the stream. Its canopy is very large. Although all the leaves have fallen, its intertwined branches block out the sky.
Cheng Che lay down under the tree, his hands behind his head.
The winter sun shone through the branches, casting dappled patterns on his face.
He closed his eyes, listening to the sound of the stream, and felt very comfortable.
Anyone would be happy to have two beautiful women lying next to them.
He opened one eye, glanced at Yan Ruanning on his left, and then at Su Qingyue on his right.
The two sat separately, neither speaking, but the atmosphere was quite subtle.
"You're going to Australia in a few days, right?" Su Qingyue spoke first.
"Hmm," Cheng Che said, " Australian Open. January."
"Grand Slam," Su Qingyue said.
"Right."
She turned her head and looked at him.
Her expression was serious, completely different from her sulking demeanor just now.
"You will win," she said.
Cheng Che looked at her and smiled.
"I will win."
Yan Ruanning sat on the other side, listening to the conversation between the two without saying a word.
She drew circles on the ground with her finger, as if she were thinking about something.
Just then, Cheng Che's phone rang.
He glanced at the caller ID.
Professor Liu.
He immediately sat up and answered the phone.
Professor Liu.
" Cheng Che." Professor Liu's voice came from the other end of the phone, filled with barely suppressed excitement, "I've read the paper. From beginning to end, three times."
Cheng Che held his phone, remaining silent.
"I have a question for you," Professor Liu's voice deepened, "Did you complete this all by yourself? Independently?"
"Yes," Cheng Che said, "I made it myself."
There was a moment of silence on the other end of the phone.
Then Professor Liu took a deep breath.
"Good. Very good," he said. "This proof is flawless. The logic is sound, the argument is rigorous, and the connections between the three branches are beautiful. I've read papers for so many years, and I haven't seen such a clean proof in a long time."
Cheng Che smiled and said, "Thank you, Professor Liu."
"I'll be the corresponding author," Professor Liu said. "I'll submit it for you this week. Submit it to Annals of Mathematics; they'll be interested in this result."
"Good."
"Also," Professor Liu paused for a moment, "Don't tell anyone else about this yet. I'll notify the department after submission, but don't spread it before it's officially accepted."
Cheng Che understood.
This isn't because he's afraid someone will steal his first author title, but because he's worried that other professors will be eyeing Professor Liu's corresponding author position.
There's a hierarchy in the mathematics world too; for a paper that gets published in a top journal, the order of authorship is often more important than the content itself.
"I understand," Cheng Che said. "Thank you, Professor Liu."
"No need to thank me," Professor Liu said with a smile. "You're my student, who else would I help if not you?"
After hanging up the phone, Cheng Che put his phone back in his pocket.
He leaned against the tree trunk, looking at the branches overhead and the sunlight filtering through, and a smile curved his lips.
Talent, that's impressive.
Yan Ruanning and Su Qingyue both looked at him, one with curiosity and the other with doubt.
"About the paper," Cheng Che said simply, " Professor Liu said he'd help me submit it."
Su Qingyue was taken aback. "So fast?"
"Um."
Su Qingyue looked at him, her eyes overflowing with tenderness, and said in unison with Yan Ruanning, "Then congratulations."
Cheng Che smiled at them both, then closed his eyes again.
The babbling brook flowed in my ears, and the winter wind carried the scent of hay.
These days are pretty good.