Summary of the program Design contest of ACM University students in Henan province

Another year of the provincial race day, there are so many so many slot points.

But first or mention, good touched finally did not eat in the cafeteria, the hotel's food is more than the school restaurant is delicious ~ ~

Journal the process of the game:

First is the first day of the warm-up, B want to rob a blood, the result more said a few words, resulting in a minute slow. Then I and wx think a problem good trouble to give Psq practiced hand ~30 minutes to finish the discovery server collapsed. Just put the code in the beginning to observe the surrounding ~ do not know when the server was resurrected, and handed over 1 a. Then later learned that the original does not have to consider the parentheses of the nesting, the difficulty of an instant drop a lot ah. Then, when testing, we found that the array size does not affect the expression of science. There was no significant discovery of anything else.

Then the second day of the official game, first WX read a question, psq read H question, I read the B question. WX said a problem is yesterday's a problem must have more than this problem of water, this problem first put put. Then I read the B question, found that the sample B is very strange, there are spaces between the number of hairs, put them to the end of the found in line with test instructions, and then directly think that it is printed error to tell WX Water DFS, the input space is not considered. Then 10 minutes decisive WA, during the discovery of someone A has a G-question, called psq translation and I think good ideas, print B to take over to write G, 10 minutes to finish writing also decisive WA. At this time WX said I god pit, B topic clearly said the input exists space, forced to tell the error test instructions. So I printed the G question, WX changed the B question. A few minutes on the AC, and then found that the G problem also test instructions leakage, test instructions request to ignore rounding, and I considered, decisively change the AC. At this time found several teams have a and F questions, Nanyang Star Team 3 first. Then and Psq translated F, and WX conceived a frame. After reading the discovery of the F flood, 10 minutes to finish 1 A, boarded the first place. Then psq think C, WX took over a question, I read d. PSQ said C to build the side directly to do may be T, I said D is a minimum spanning tree PSQ concept under the framework, I give a problem data. 2 minutes later PSQ said the D problem, 10 minutes can be knocked out, and then continue to think of c. 72 min WX wrote the test data over 1 A, stabilized the first. Then PSQ took over the 85-minute 1YD question. Then also came up with the C problem of the building Edge + optimization continue to write C, and I and WX began to push the e-question. E Start thinking that epidemic prevention station can be repeated start, think of a DP to write a good frame, to help the C problem good data. 144 minutes C WA, check the code 10 minutes do not know why wrong, has been out of the data plus testing, to 200 minutes suddenly popped out of the C question over 144 minutes 1 A, 28 minutes advantage of the second column first. During the discovery of the question e epidemic prevention Station can not be repeatedly opened, declaring DP thought burst. Next provide a few ideas for psq reference to H, I and WX want E. Then psq found helpless, decisively remind him to re-read the problem, the results found that the title must be convex polygon, instantly reduce the difficulty, start knocking. And I and WX for the e Question No idea, WX said to see if the iterative deepened search can be water, and I found very much like DLX to see if there are ready-made template now learn. Then found no data on the H-question, this time psq constantly debugging has been unable to sample, during the WX knocked the E-question T can not water, has sealed the board we are still the first. 296 minutes of debugging successful sample, directly submitted 1Y exclaimed (here seems to frighten the giant giants next to t_t, expressed hope to understand:) The remaining 4 minutes to WX to see if E can be pruned. Finally there is no AK, a little pity. After the game asked the various venues have 7 questions, found that there is no, on the peace of mind, the success in 3 years after the victory of the light Court provincial champion!

The following is a simple explanation:

Question A

Simple string emulation.

For a chemical equation, the chemical relative molecular mass is followed by an equal sign, and there is no nesting of parentheses. Just once over, the record will be fine.

Question B

DFS, similar to hdu1241,.

0 represents the sea, 1 represents land, the number of islands, and the largest island area, the Island 8 direction extension.

Question C

The shortest circuit, the feeling is a classic problem, it should be the original question.

To n bus one-way line, m stations, the minimum number of transfers from 1 to M points, can not reach the output No.

For one-way lines, each site built a one-way edge weight value of 0, the other sites built two-way edge weights of 1, 1 to M to find the shortest.

Question D

Minimum spanning tree, blue Bridge Cup city construction (previous)

N Cities, giving the value of each city's water supply, the price of each city's plumbing, and the minimum cost of water for all cities.

Set up a virtual meeting point, all cities and their built-up, the weight of the value of repairing water, the minimum spanning tree.

Question E

Do not understand the positive solution, the feeling is DLX.

Here is a pity, has been planning to learn, but think that the province will not be so difficult, think of the province after the study, resulting in no AK, really back pot.

Question F

Water questions, judging points in the first quadrant.

Question G

poj2018 original question

Water problem, violence to protect peace.

Question H

Calculate geometry + Shortest circuit

Line segment when the point with a fork to judge the construction side, run the shortest way.

Next, Summarize:

Okay, don't say a word, say the question of existence. As a result of the team only 22 times WA's culprit, the most important thing is to seriously read the question, B question g H is because the problem is not serious enough to read more and more cards a little time. Then it is still not enough knowledge points, if you know the algorithm have learned so AK is no problem, although the title, but no AK is a bit regrettable. Then is the hope that the light courtyard of the study younger sisters next year province race refueling!!

And then it's time to spit out the slot:

(1) A, the original title of the warm-up, B said it is similar to the original question, the C-question feeling is the classic problem estimation is also the original question, the D Question Blue Bridge Cup original problem, G problem poj original problem.

(2) Plus F water problem has been E, H two super difficult. The feeling of the provincial race has become a pure hand speed and careful game. Throughout the audience, many teams last one hours or even two hours is basically nothing to do, the problem is not high-level, and can not let a lot of teams to do five hours.

(3) I heard that the server is not stable, the latter is basically a semi-artificial judgment, especially the problem of C is missing the phenomenon of severe.

(4) A good bonus? t_t

Finally say personal feelings, listen to the teacher's explanation, said it is a variety of difficulties to reduce the problem of Henan province, many schools can not break the silver medal in the regional competition. In fact, I think, the quality of the provincial race is a big problem, here we have to boast about the quality of our school game, is no matter the freshman sophomore junior, there is a simulation problem algorithm, the perfect distinction, to ensure that each team can do five hours, after all, is the regional gold medal team out of the problem ah. So I hope that the province can be in line with this aspect, weak to learn from others and consult, no bonus on the quality, at least to upgrade the problem, this is after all the situation in Henan province, not only some of the school competition gold medal What, to deal with each school is not very harmonious appearance. And of course because I don't want to. Henan province is always known as the weak province. Then is the hope to strengthen the rigorous test, ah, the error of the data to the player's mentality and time is a serious blow, as a sponsor, the sample space is missing this error at all I think is a low-level error, as long as there are two different code, is completely can be measured out. But it is also good to say that the provincial races, just want to make everyone better, and finally do not know what to say. Let's get here.

Summary of the program Design contest of ACM University students in Henan province