### Imakf's blog

By Imakf, history, 4 months ago, ,

Hello codeforces!

CSP-J/S(Certified Software Professional-Junior/Senior) of China ended. CSP-J/S (or you can say NOIp ,but it has been dead) was held by OI rules. In OI rules, every problem has the same score distribution $100$ points. In one problem, there is several testdatas (like $10$ ,$20$ or $25$). Every testdata has the same score distributions. Once you pass a testdata, you can get the score. You can submit your code during the contest, but can't see the result. The organizer will judge all the programs together after contest.

I'd like to share the problems of CSP-S here! Hope you guys enjoy. Don't mind my poor English, I spent a whole afternoon translating.

D1T1 code
D1T2 brackets
D1T3 tree
D2T1 meal
D2T2 partition
D2T3 centroid

• +71

 » 4 months ago, # |   0 Auto comment: topic has been updated by Imakf (previous revision, new revision, compare).
 » 4 months ago, # |   0 What does exchange each number on itself in D1T3 means? Do you mean swap the number on vertex $u$ and $v$ ?
•  » » 4 months ago, # ^ |   +3 Yes, I mean swap the number on the vertex... Sorry for my poor English
 » 4 months ago, # | ← Rev. 2 →   -11 How do you solve D1T2 and D2T1?
•  » » 4 months ago, # ^ |   0 The most difficult OI in China? Do you know NOI?
•  » » » 4 months ago, # ^ |   0 I mean provincial level
•  » » » » 4 months ago, # ^ |   0 for provincial level,there is a more difficult OI what province made by themselves
•  » » » » » 4 months ago, # ^ |   0 I don't mean the team selection contest for each province, I mean the national provincial-level contest (CSP/NOIP)
•  » » » » 4 months ago, # ^ |   0 sorry,my English is pool, so maybe you can't know what I say(sorry
»
4 months ago, # |
Rev. 2   +3

Here is some other things about the rules in China.

## Time

The contest spans over $2$ days, named day1 and day2 respectively. You can see which day the problems are from by the number after the letter D and the no. of problem it is in that day after the letter T. In each contest day, contestants are required to solve $3$ problems in $3.5$ hours.

## Supplies

In OI mode contest, contestants will be provided with:

Hardware:

• PC
• Papers

Software:

• OS: Windows 7(in some provinces) and NOI Linux(in all provinces).

• Developing Enviroment: DevCpp(in computers equipped with Windows), Lazarus, Anjuta, GUIDE(a disgusting IDE made by BUAA), and various command line tools including vim and gdb.

Problem

• A PDF statement

• Large samples (Samples with larger test cases, it is believed that this is provided in order to make the contest more similar with IOI modes, but it has received mixed results)

## Judging

The programs are collected after the contest for each day ends, but the results won't come out until early December, thus, the contestants must take part in day2 without knowing the results for day1.

The judging server is Intel i7 CPU since 2018, and AMD Athlon, an ancient model, before 2018.

Each problem contains $10$ to $25$ tests, when you pass a test, you get a score assigned to it, usually, points for each test in one problem is equal.

Some Online judges, like Nowcoder, generates tests immediately after contests ends, it is called unofficial tests. Participants may use them to determine the approximate points (s)he may receive. However, the results may differ vastly, and should be used with care.

Problems in China requires input/output via files, and many people fails each year with filenames (remember, you do not get a chance to test your program on the actual server during the contest!) For example, a friend of mine misspelled brackets to barckets, and lost $55$ points, it may be vital for him because his point is dangling near the line to the first prize now.

•  » » 4 months ago, # ^ | ← Rev. 2 →   0 In some provinces (such as Shaanxi, the province I come from), there're still some computers with Windows XP, but no ones with Linux.
 » 3 months ago, # |   +8 Is it true for D2T2 that the optimal solution is a partition where the last segment has minimal sum?
•  » » 3 months ago, # ^ |   0 Yes.
•  » » » 3 months ago, # ^ |   0 Do you know how to prove this fact?
•  » » » » 3 months ago, # ^ |   0 http://matthew99.blog.uoj.ac/blog/5299 This blog may help you,but it is in chinese.
•  » » » » » 3 months ago, # ^ |   0 Thanks a lot! (I can read Chinese :))
•  » » » » 3 months ago, # ^ |   0 Many people solved this problem for find patterns