14 Xi 'an semi-finals Summary

14 Xi 'an semi-finals Summary

ACM

For the first round of the semi-finals, I can finally write a summary post.
Summary post = slot post? Almost. (Something happened when I left. I am in a bad mood now. Let's just tap into the water)
Use the total score for the article structure.

Xi'an trip inVarious aspectsI am raised a lot.
In this competition, I personally felt pretty good, at least not playing abnormally, and successfully won the bronze medal. (I'm touched by ing. In fact, I am ready to fight Iron. Thank you for the buff that I added before the competition for my mom, cousin, zlx, wjx, and other kids shoes)

Before departure. 
This stage was very busy before the competition and had to deal with various things. However, I made up a lot of time to prepare for the competition, saying that the preparation was actually a temporary blow to Buddha's legs. All kinds of offline questions are solved before the competition, and then the network is disconnected and the dormitory is flushed. During the game, I practiced one game with my teammates on the same day of the week (in fact, I practiced one game in total). I found that I could only beat the iron, but I could only silently go to orz, then, more questions will be taken offline silently.
The tree chain in todolist is finally displayed to me a few days before departure. It is not that difficult to find.
Before the competition, I also read several sets of questions from ecjtu's friends about FDU over the years. I would like to thank them here. Although they did not play well in this competition, they are also very good and hope they don't take it too seriously.

Aircraft. 
This is the second flight. The first time I went out with my dad when I was a child.
In the group, it was said that when we got on a plane, all kinds of "wow" and "ym" were actually the planes we used to pay for them. We came back to the train.
Xiamen Airlines plane.
We walk together with three of us and our big sister teachers.
The plane soon arrived in Xi'an in just a few hours. It was nice to sit by the window and see a lot of scenery along the way. I have to say that the flight is still a test waist, and my teammates Shouted Old waist that night.
What's interesting is that we fell asleep when we landed the plane, and the synchronization rate was quite high.

Hotel.
Two rooms were selected by the way during the registration competition.
After arriving at the airport, it was more than 4 o'clock and it was very difficult to find out how to take a bus from the airport to the hotel in the evening. Then I asked the airport attendant, and it took a long time to go back to the hotel after boarding the airport bus.
I never imagined that the city was so far away in the hotel and the competition campus. After several hours of bus, I got off at the University of Political Science and Law, and there was no bus everywhere to go to the hotel, so I had to fight.
The hotel is divided into three areas. We are located in three areas. It is said to be a hot spring Hotel. When I registered, I met a large team to register. I did not dare to talk about low EQ. "The kuangbin team of other schools won the final place in Anshan ", I can only think so. I met a lot of players along the way, and they all looked like orz in my eyes.
The luxurious standard room feels good, that is, the water is too small. I'm going to talk about the hot springs? Later, we found that there was only a hot spring orz for renting a villa. Many people lived in the villa together, so we could only live in the standard room. I also brought a swimsuit.
We hadn't eaten yet because we arrived at the hotel, so we put down our luggage and ran to a nearby barbecue stall to eat a few barbecues. By the way, we ordered the legendary Mutton Bread, it is actually the dough that is cut into cubes.
Then I went back to take a bath and have a rest.

Warm-up match.
Competition and hotel arrangement are undertaken by Northwestern University of Technology.
Sure enough, it was normal for the warm-up match to be held for one day and the formal match to be held on the same day.
After breakfast buffet at the hotel in the morning, I took a shuttle bus to the campus. After I signed my clothes and creden, I had nothing to do. The opening ceremony and warm-up match were in the afternoon.
So I went to Northwestern Industrial University. As I got up early in the morning and fell asleep, I ran to the canteen for dinner at. After dinner, I went to sleep over there.
In the dining room, I also had a base with codebattle, And I had such accomplishments as the sophomore year, which I admired.
The opening ceremony will be held only when the time passed in the canteen is over 1 o'clock. Then the opening ceremony began. The competition was not only sponsored by IBM, But Huawei, Jiangyou, and iQiYi were also joining in. So people came to speak at the opening ceremony, just remember the Secretary-general of acmicpc Asia (?) Talking about ACM in China is very funny, saying "playing iron and copper" is a joke.
There were more than 260 teams participating in this competition, which was unprecedented. However, the organizers have worked very hard and I feel pretty good.
Then the Closing Ceremony will end at less than, and the contestants will move to the stadium side. They will sit in front of the stadium at over three, and the questions have been fixed on the table, the competition started at half past three. So we waited until half past three on the computer and the subject. We need to vomit that the computers prepared by xigong University this time are not very good, and there are many problems with the display screen. The keyboard actually uses the game key space,\I think no one will get used to it.
The warm-up match started. As you can say, zyw first knocks on the configuration, and lyj and I start to read the question. After reading a, I found it difficult to understand the meaning of the question. Just simulate it, so I started to think about it. Later, I found that the double floating point may have a problem, and there was a problem for half a day. Let's take a look at the various things of the entire site D. We found that D is a simple application of map. After I quickly passed D, they were discussing B and found that the first problem was to reverse-order template question. So zyw began to work on the template. At this time, I saw a lot of C in the audience, so I checked C with lyj and found that C is a simple computational geometric template, and I can immediately see it. However, this was a warm-up match, so we waited patiently for zyw to finish the part of the reverse order. Then he thought about the second question of B. I started C. On the way, he said he had an idea and wanted to check it out. I thought C would soon be able to get through, so he gave him the keyboard. He didn't figure it out after a while, so I printed a copy of the code and continued to work on C. At this time, we found that the warm-up match was just two hours, so we gave the C to us in the last half hour, and then we watched B together. I forgot about the reverse order of merge. I couldn't even figure out how to solve the first problem, but I couldn't even think about the second problem. So I made a few rounds of A, re a few rounds, and then the competition was over. Generally speaking, CD is 1y in the second half.
Later I heard that A is a very abnormal simulation question, and there are various pitfalls. No wonder I have to kneel down... what double does not have a floating point, but other traps are everywhere. According to the time when the speaker spoke, the question was originally placed in the formal competition, which weakened the placement in the warm-up competition, and then added various pitfalls to become more difficult than the formal competition... it's really bad to do a first.
After completing the competition, I printed some additional materials and went back to the hotel. I made a discussion at the hotel and wjx, and stayed in bed for a night (don't think too much ).

The official competition.
The second day after the warm-up round is the official round. The round is from. I was a little excited at the entrance.
Then the official competition began.
As a person, I will repeat the configuration and start to look at the questions. I probably flipped through the question and didn't see it at a glance. F was very short and I found it hard to do it.
After about five or six minutes, we brushed down the list and found that a had passed a lot. Then a must have signed in, so I tried to read a again, it seems that the number of sequences can be directly divided by 3, but it seems that there are other "Alibaba" conditions that do not know what to do, so I carefully read them several times for the sake of insurance, it seems that the result has nothing to do with "Alibaba". After I click it, I find that more than 100 of the teams have crossed the list. All the teams except the last one, WA, are 1A, so we made a bold decision, 15 minutes and 1 y.
We keep in mind the principle of "Don't grab a blood, keep up with the troops" of bin God. After refreshing the list, we saw a lot of people who have also had K questions. So we ran to see K, I found that it was a classification discussion to find a regular question. I drew a picture on paper, but I still couldn't draw a conclusion. I have been thinking about entering a negative number. Later they said there was no negative number, and I started to do it. I first wrote a brute force table and found the rule, then I spent a lot of time thinking about it. Finally I wrote a simulation that would find the rule. After a while, I finally passed the example. For the sake of insurance, I wrote a data generator, generated 1 K sets of random data, and handed it back to the brute-force pattern. Wa got a hit. At this time, we found that there may be a special example, so we tried several groups, found some bugs, wrote several special judgments, and handed in the results, 46 minutes and 2 y.
(Then, no more questions have been given to the list .)
When I was engaged in K, I found that F had been a lot of people, so my teammates started to look at F. After K was done, I also specialized in F with them. The meaning of this question is a total of M colors, select K to dye n flowers. k colors are required. There are several dyeing schemes. It is similar to DP or a mathematical problem, but it is unlikely that the data range is DP. If you think about it, teammates will give a formula,C(k,m)*(k*(k-1)^(n-1))Then I thought about how to use this formula. It was terrible to use high-precision complexity. I remembered an article about acdreamer offline before the competition, and I did not regret it. I thought about the complexity of O (k). Although there are 300 groups in this example, most of them are small data. Although there is no time, the complexity should be similar, so we started. I did not do a lot of math problems. I tried to find the reverse yuan. I used the bin God template and did not know the complexity. I tested it and found that preprocessing was acceptable. Then the raw edge was used for edge debugging. Finally, an example was created. The samples with the maximum range of 100 groups were tested locally. Although they could not be verified, the time was 1.2 + S, still not very reliable. I knocked on an input and output plug-in and found that the time was longer. After removing the input and output, I made a bold mistake and Wa. In fact, WA is much better than TLE, because if it is t, it means that the complexity of this question is not enough, and the solution may not be what we think. Then, we kept looking for code implementation errors and found that there was no problem. We called zyw to write Java Big Data brute force and found that eclipse was useless due to some problems. So I wrote about the python brute force attacks. After several groups of attacks, I found that the answer calculation was correct. It seems that there is a problem with the idea.
It has been almost an hour before this time. At about 12 o'clock, Chinese food has been delivered. Chinese food is a goat, a hamburger, a ham, and a pack of milk. I quickly killed my hamburger, and I had no appetite for anything else.
After eating Chinese food, I asked my brain to take a break and began to think about the formula proposed by my teammates. I drew a picture and found that the problem was very serious, that is, the question required K colors, however, the teammate's solution also includes<kNumber of solutions. So I thought about it and felt like I would subtract it.(k-1)Number of solutions, and then after a pass, use python to correct the camera, or Wa... orz. (How can I see my father-in-law in front of the TV if I want to tie the tie to tat?) Now I am close to the closed list. Sadly, I drew pictures with my teammates, wrote several answer trees, and found that whenk>3It's time to kneel. So I drew a lot of formulas on the paper and found that(k-1)It is not correct. Then, I calculated several values using python. After calculation, I found that the proper formula is used. Although we have already closed the list and our rankings are also in the iron area, I am still very calm, and then calmly debugged it, handed it in, and waited for a few minutes without any results, my teammates told me if it would be TLE, So I optimized it.C(k,m)I wrote a line with the content in the back, and handed it over again. After a while, I returned to the last wa, And the whole person was not good. I can only look down at the answer tree and look for a posture. Now there are only 10 minutes left. It's hard to go back and see my schoolmates. At this moment, the message "yes" was not returned before. It was incredible. My teammates cheered. I was so embarrassed when a group of people looked at us. Where did I go to optimize the wrong tat, I thought there was a problem with the idea. Then my teammates began to eat...
Is it so high to get a copper? If I get the silver, I will run the whole game in the last few minutes.

After the game.
After the competition, I reported my score from various places. The closing ceremony began. Huawei's presentation and entertaining speech were lengthy and followed by a mobile phone. Then I explained the question. The speaker did not come, but I explained the two magic cows of FDU, just like talking about crosstalk. K was related to GCD when I saw a variety of questions about God. No wonder I was like moving and division... All kinds of questions can't be said.
Then the awards were rolled out after the cards were obtained.

Travel.
After the competition, I took a three-or four-hour bus to the hotel near the railway station.
In the evening, I went to a small store to have a single stick, and then went to the clock tower and the wenfang to eat fried big squid.
The next morning, I went to the Terracotta Warriors and ran the Wild Goose Pagoda. Then I took the 22-hour train back.

Touch porcelain.
When I tried to catch up with the train station, I even met porcelain. My teammates "knocked down" an uncle and another associates immediately came around to cheat money, which was very professional. The brother-in-law immediately picked up the phone and asked for an alarm. After one of them was scared, we helped the guy on the ground to his car and then continued to catch up. The guy in the room was driving around and chasing us, then we escaped him from the station.
The field is really terrible, and it's up.

Weather.
The weather in Xi'an is really bad, and smog is very serious. I thought it would be cool. Later I found that it was similar to Fuzhou, and I didn't take out many coats and cotton coats.

In short, the game played well. It depends on luck. However, this fierce competition in Xi'an is not very appetizing, and it is all about mathematics.
Xigong University has done a good job. It is really hard.
Alas, the competition and tourism are so tiring that my neck is broken when I put my 22h train.

I went, wrote a Summary of the stinking and long competition, and I was so embarrassed to send it out.

14 Xi 'an semi-finals Summary