Travel Notes of CTSC2018&APOI2018
Day -1
Depart in the evening, from Changsha to the soft sleeper of the imperial capital.
However, a middle school in Changsha took the high-speed train and arrived earlier than we left later.
Day 0
In order to write a travel diary in a serious way, I decided to refrain from complaining about the hotel in the blog.
Lunch is in the eighties. The school is very nice, and the computer room is also good (mainly because the machine is well configured).
There is actually a Day 0? I opened it and saw something familiar.
Day 1 of the nine-province joint entrance examination. By the way, I haven't written the coat yet.
Happy typing on FFT and NTT, and don't want to write about other topics. It went on like that until dinner.
I looked at last year's CTSC questions at night. It doesn't feel good.
No matter what, come on tomorrow.
Day 1
In the morning, I found that the meal ticket was lost. qaq
The exam starts at 8:30? No hurry, no hurry.
But hasn't the time come? ? ?
I'm so sorry, we pigeons. --- loose loose
The 415 examination room said that the examination will not start until 9:07.
It is not easy to look at the question first.
T1 faceless mask(God tm shameless)
First look: Hey, how can I only be \(O(2^Q)\) violent, only \(20\) points ah qaqqqqq
Second look: It seems that \(u=v\) I can write! Simulate directly! There is \(30\) spicy!
Then go to see T2 wronganswer violent writing and hang up and
score according to the meaning of the question. . . How much can this data go through? . .
Let's look at T3 green, the lord of green mushroom (Yinxun)
, violently arrange violent check, complexity \(O(T*n!*n^2)\) ?
Hash each state and look up the table directly is \(O(n!*n^2+T*\log n!)\) .
Then the special property of \(L_{i,j}=j\) is \(ans=2^{n-1}\) .
\(25\) points? ? ?
The three questions do not add up to three digits, which is obviously not enough.
Very wisely decided to just \(T1\) .
At 11:00, the condition \(m_i\le100\) was found . If I see me later, I might be cold.
That is not, directly set \(f_{i,j}\) to represent the first \(i\)What is the probability that an individual has a \(j\) drop of blood now?
Operation \(0\) direct \(O(m_i)\) violent transfer.
Operation \(1\) ?
I thought about it for a long time. Consider each person to be selected individually, and then process the remaining \(k-1\) individuals to give \(g_i\) to represent the probability of \(i\) individuals surviving. Then this person's answer is \(\sum_{i=0}^{k-1}\frac{g_i}{i+1}\) times the probability of this person surviving.
This is \(O(Cn^3)\) , you can pass \(70\) .
Then look at \(100\%\) , it is obviously \(O(Cn^2)\) . Witty found that the \(g_i\) array processed earlier is a backpack, and considering each person is equivalent to inserting \(k-1\) items into this backpack, and each person is also inserted \(k -1\) times.
First deal with \(k\) personal backpacks and then consider deleting one of them?
According to the originalThe \(dp\) formula can be reversed.
Written 40 minutes before the next test. I shot 100,000 sets, which is comfortable.
Then T2 is a \(O(n^2\log n)\) tree section, T3 \(25\) points.
The pre-test score \(100+35+25=160\) .
Before the lecture, a person went to the computer room to see the results.
\(100+40+25=165\) .
The tree section of T2 has actually passed. Because I didn't judge that the two points are in the same position, then \(WA\) a point.
The distinction is not high today. Among the non \(15\) people, there are probably \(\frac 14\) people who have cut T1, and then T2 is not there whether it is written with some reasoned and well-founded points or messed up and got more than \(45\) few.
Compared with the loss of \ (10\) points \(Au\) in the winter camp , I don't think today's few \(5\) points will make a big pot. It's a big loss for not writing about messing around.
(But having said that, even if I were to write a T2 mess now, I can't guarantee that I can get a higher score than \(45\)
) The messing ability needs to be improved.
But what made me even more unhappy was that I forgot to take the USB flash drive to save the files. After I finished the question, when I went back, the computer room was already locked qaqqqqq.
Come on, Day 2.If you don't take the exam tomorrow, you can gtf at night.