Summary of three recent matches

10.25 morning provincial regular center simulation Competition

The question of the competition just came out, and I became nervous when I saw the person who asked the question, because I had also done a question for him during the summer vacation, and the question was hard to reach the highest score of more than 100 points, so again, it is inevitable that some psychological shadows will be placed on his questions.

This mentality directly led to my mistakes in the first question. Because I thought that the simulation competition should be more difficult, I thought it was a dynamic rule without thinking about the first question, and did not think about it in a simpler direction. I first thought of the interval motion gauge, but I found that I could only get 50 points. After thinking for a while, I still had no idea. So I made the interval motion gauge a good one and then made a second question.

The second question is a good question, but because of the poor data, the AC can be easily implemented by brute force and optimization. I didn't know the strength of the data at the time, so I quickly completed the brute force with the consciousness of taking some points, and it didn't take much time on this question. The final result is surprising.

The third question is not difficult, especially compared with the third question of noip. However, the topic description and input in question 3 are cumbersome, which directly leads to my annoyance. After reading the question many times, I understood the question. In this situation, I subconsciously think that the third question is very difficult, and the score of 60 points is easy to get, so I did not think about writing the 60 points, then I put the third question aside. After the exam, I still regret it because it is not difficult to think about it.

It took more than an hour to complete the deception of the three questions, and then began to think about the full score Algorithm for the first question. It took a long time to think of linear motion gauge, And the complexity was completely okay. However, it took a long time to implement and debug the linear motion gauge, but it was different from the interval motion gauge that was previously written, then I manually simulated several groups of data and finally found that the interval motion rules written at the beginning were wrong. After that, I could not perform the same operation. Instead, I could only manually simulate the same operation on small data, the answers that are directly simulated from left to right are the same as those obtained by the motion rule. With an attempt, I used the stack to implement the simulation algorithm, and then matched the pattern and simulation. I have been debugging for more than an hour and have more than one hundred lines of code. For simulation, as long as one stack is used, the code length cannot exceed 20 lines. At this time, there is no time to write the third question, because even if you think of the third question, it will take a lot of time to implement it.

Then I switched to some minor optimizations of the second question. The optimization of the second question was completed almost at the end of the writing time.

In general, my policies are correct,Take the brute force score first, and then think about the full score algorithm.. If I didn't give up the third question and want to concentrate on the third question, maybe the third question can be AC, but it is likely to lose a large number of scores for the first question (because the range dynamic rules at the beginning are wrong ). As a matter of fact, I only scored 50 points after writing the code for ten minutes, which is very cost-effective.

However, the disadvantage lies in the psychological status.Mistaken estimation caused by fearSo much time is spent on the simplest first question. If you can calm down and analyze the first question, it is not difficult to think of the correctness of the simulation algorithm.

 

10.26 morning Secondary School Simulation Competition

Like the previous day, the name of the person who asked the question suddenly becomes tense.

Then I started to read the first question. I did not understand it after reading it several times.

Then I read the second question and found that it was a question someone asked for help. I once saw it but did not pay attention to the solution at all. So I began to regret it during the competition. The questions are easy to understand, but there is no idea at all. I feel that I can only lie to 10 points at most.

Let's look at the third question: Static Interval query. A line segment tree is a data structure that I am familiar with, so I have also thought of a line segment tree, but I have not thought about it. I found that the data range was 70 points, so I wrote a 70-point algorithm according to the usual routine. I checked several small data sets and found that there was no problem, then begin with the first question.

I manually simulated several groups of small data on the first question, and found a little pattern and had an idea. So I did not hesitate to write the DP Method, and I felt that I could score 50 points. Continue to perform the chaos and find that many statuses are completely unavailable, and there is a bit of meaning in the Division. So I wrote a GCD-like algorithm, but changed it to a shift and subtraction algorithm, there is no problem with the video detection. At this time, I began to have a little confidence and felt that the first question could be AC. However, after the discussion, I found that if the limit data is met, it is likely that the conversion and subtraction will time out, and it is best to perform the division. However, the data is more conscientious, but it is still AC.

I still have no idea about the second question, so I read the third question again. Then we found that the line segment tree was completely feasible, so we were very happy to write the line segment tree. Because I am familiar with it, I wrote it right once. Then I found that there was no problem with the beat, and the constant was still quite good.

There is not much time to finish one or three questions. I still have no idea about the second question, so I have to write a 10-point algorithm.

For this competition, we first made the same mistake as the previous day, that is, fear. However, I followed the rule of writing brute force first, ensured the basic score, and then wanted the full score algorithm, so I got a good score. The second question is too late to think, but it is still a bit of regret.

 

10.26 uoj test Round 1 at night

This is the worst I have ever done in a few days.

The first question is to deliver the score. I was very happy when I saw it. I finished the code without thinking about it. Then we found it was wrong. At this time, the mentality is a little unbalanced. After deleting, deleting, modifying, and passing through two examples, I went to the second question. But in the end, the first question only scored 70 points. The full score algorithm only needs to be slightly modified in the initial error code.

The second question is a little difficult. After thinking for a long time, I had no progress since I encountered a bottleneck. After more than an hour, I decided to give up the entire game. This is because the status is no longer available.

Of course, I did not go to the third question.

The performance in this competition is worth mentioning. First of all, for the first question, after several minutes of coding, we found that the sample could not be used. This is indeed a great blow and directly affects the mentality. Then I deleted all the error codes and replayed them without thinking about them. This is actually completely unnecessary. If I was able to think about it a little bit at the time, I would be able to easily AC it with slight modifications.

For the second question, I started with the AC. Too high goals lead to anxiety when I cannot think of a positive solution. This is actually a common problem for many people.No Target found. In this regard, CLJ once summarized in his post that in a year's ctsc, he only wanted to take the first place, which completely disrupted the original good exercise strategies and habits, eventually failed. From my perspective, my goal is to wait, not to get full marks.We should try to get more scores instead of thinking ifACAll questionsNot to mention that you have no full score. If I was thinking about how to get the most scores, I may choose an algorithm with only 60 points for the second question, but it is far better than the subsequent results, at least I will try the third question.

 

Therefore, the summary of the above three games is:

1.Clarify the goal, correct the mentality, and obtain more scores as much as possible;

2.Write brute force statements first, and then write positive solutions, especially when your algorithms are uncertain;

3.Weigh the gains and losses and write more cost-effective questions;

4.Be confident and never be afraid of difficulties.

Summary of three recent matches