Originally, Su Mu thought that today would pass so peacefully.

Code words, brush up, read the book, and then meet the second exam tomorrow.

However, things changed slightly after dinner.

Dai Binbin was still sleeping in the hotel room, and Su Mu was eating alone.

After eating, he was about to continue back to the hotel room, but he did not expect that twenty or thirty people had gathered in a corner of the hotel restaurant.

Yue Hao and Yin Hong were also watching from the crowd.

I have to say that Yue Hao's social skills are really strong, because Yinhong seems to be a boy who doesn't like to talk much, but after getting along for a while, Yue Hao can also talk and laugh with him.

When Su Mu approached curiously, Yue Hao greeted him, and then continued to look at the center of the crowd.

Su Mu looked in his direction.

Now it was a brown-and-yellow boy in a black tracksuit playing chess with a small-haired boy.

The brown-yellow haired boy was Caucasian with a high nose, and although he was sitting cross-legged, he could still be seen to be tall.

This inch-headed brother is a black man, and he can't tell which country it is, but looking at the number of chess pieces on the field, he obviously fell into disadvantage.

A few students took out their mobile phones and seemed to be taking videos, and not only that, but in addition to these students who were around, there were even a few people who looked like teachers and watched carefully.

"There's something to this Ender."

Yue Hao whispered:

"He's won four or five in a row."

"Ender?"

Su Mu was a little curious, but he didn't expect Yue Hao to know foreign friends.

"It's the one on the right."

Yue Hao pouted at the brown-haired boy.

"It's the U.S. team, I heard that math is very strong, and it's almost your current position in our Chinese team."

Su Mu was stunned: "Huh? Where am I? ”

"The position of the big guy." Yue Hao laughed.

"Cut, you don't have to be worse than me, okay?" Su Mu shrugged his shoulders, Yue Hao likes to pretend to be new.

After getting along during this time, Su Mu had already discovered that in the case of not hanging up, this guy's strength was definitely not weaker than himself and Dai Binbin.

"Then you see, I'm back at the hotel."

Su Mu glanced at chess again, although these top math students were very fascinated, but he was not very interested in this.

"Why are you walking so fast, I want to compare with him later, don't you want to cheer me on?"

Yue Hao put his arm around Su Mu: "We are a team, do you see anyone over there who is recording with a mobile phone, I think someone will definitely post this little game on Facebook." ”

"It's just hair...."Su Mu shrugged.

Yue Hao's full name on Facebook is Facebook, which is relative to QQ and Weibo's combined social status in China, but this has nothing to do with him.

"But I don't know if I can do it, if I can't do it, I'll definitely have to play as a big guy like you, and it is said that this Ender has won some youth awards..."

Yue Hao went on to add:

"We can't disgrace the team!"

Su Mu: "....."

With the black line on Su Mu's face, he knew that Yue Hao was fighting with this mind.

Moreover, he even had a little premonition of the plot that followed.

"I don't know how to play chess." Su Mu shook his head: "You guys play... I'd better go back to the room first, Dai Binbin hasn't eaten dinner yet. ”

Su Mu glanced at the chess game.

Now that black guy has abandoned his son and lost.

The latest to play is a short girl, and she is also one of the few girls.

Many of the contestants exclaimed and laughed, and the girls came on the court, attracting a lot of spectators.

But after Su Mu patted Yue Hao's shoulder, he still turned around and left.

He really doesn't know how to play chess.

Although it is said that you can try it temporarily, mix a skill out and then add some upgrades, but if you waste a few skill points just for fun, it is really a loss.

If it was a regular competition, Su Mu might really participate in it, but now the small scene here is not worth Su Mu at all.

......

......

After returning to the hotel, Su Mu didn't pay attention to the outside world anymore.

July 15th.

IMO Second Exam Officially Begins!!

Today's invigilator is still those people, but what is a little different from yesterday is that since he entered the venue, the invigilator who checked Su Mu's test paper yesterday has been staring at him!

Yesterday, Su Mu handed in the paper in advance at least too quickly, and the invigilator wanted to see how Su Mu wrote the questions.

Su Mu smiled indifferently and didn't care.

Today is also three questions, three test papers, each question is worth seven points.

The first question is very interesting, it is a proof of an inequality, and it is not low.

It took about thirty minutes for Su Mu to write the whole process.

The second question is a triangular proof question.

In the right triangle ABC, AD is the height on the hypotenuse BC, the straight line connecting the heart of the triangle ABD and the heart of the triangle ACD intersects the side AB and the side AC at K and iL respectively, and the area of the triangle ABC and AKL is denoted as S and T respectively, and S≥2T is verified.

This problem mainly uses the similarity and congruence of triangles, which is not too difficult, but it also requires very careful logic.

Su Mu took a little longer to solve this problem, mainly because he thought a little crooked at the beginning, and was going to draw auxiliary circles and auxiliary lines in the way of inner circles, but later he still found his thoughts, and this question took him about an hour.

The third problem has the shortest problem, and the positive integers a and b make ab+1 divisible by a^2+b^2.

Verification: (a^2+b^2)ab+1 is the square of a positive integer.

This question made Su Mu fall into deep thought.

Because at first glance, he felt that he had a lot of ideas, but in practice, he felt that every idea had flaws.

This question is actually symmetrical, and A and B can only discuss the size according to their own situation.

"Shhhhh

It took more than half an hour, and Su Mu still didn't find a good answer!!

"That's the hardest question."

Su Mu drew a lot of lines on the scratch paper, completely rejecting his previous thoughts, he originally came with a very relaxed attitude, and felt that today's difficulty should not be very great.

But now it seems that this simplest algebra problem is probably the real core of this IMO.

The most important thing is that more than two hours have passed since the exam time, and if it is according to the previous results, Su Mudu has already handed in the papers and gone out to drink tea.

Now, he can only scratch his ears and cheeks here helplessly.

That's the IMO difficulty.

Su Mu sighed a little, sure enough, he still thought that the Olympiad group was too simple, and the difficulty of the published questions did not match the actual difficulty at all!

Rubbing his temples, the Turkish brother next to him was still doing the first question, which made the corners of Su Mu's mouth slightly raised, and he felt a lot better.

......

PS: There are only two shifts today, and the red envelopes have been sent to the book friend group!

Ask for recommendation votes and monthly passes, and it will be a waste if you don't vote at the end of the month!!