Hi, Codeforces!

We are so happy to invite you to participant in The 21st Southeast University Programming Contest (Summer), which will start at May/18/2025 09:00 (Moscow time).

This round will be conducted according to ACM/ICPC rules. Therefore, solutions will be judged on all test points during the competition.

The competition is team-based, with teams of 1 to 3 people, and you will be given 11 to 13 problems and 5 hours to solve them and two of them will be divided into two versions.

Please note that the penalty for submitting an incorrect answer in this competition is 20 minutes.

All questions were created and written by Huan_YP2002, limithym and me.

We would like to thank:
1. MikeMirzayanov for creating Codeforces and Polygon.
2. CPC club of Southeast University and the seuOJ provided by SEUCPC club .
3. Science and Technology Association of Southeastern university school of Computer Science and Engineering, school of Software and school of Artificial Intelligence for all their works and all the staff involved in this contest.
4. Tobo, Anonyme, thisislike_fan, baka_killer_uuz, xukuan, Chenzq7, 9756, king_of_gamers for testing this round and giving useful feedback.
5. Last but not least, You for participating in this round.

Good luck and have fun!

Update: Editorial is up.

Hi, Codeforces!

We are so happy to invite you to participant in The 6th FanRuan Cup Southeast University Programming Contest (Winter), which will start at Dec/01/2024 09:00 (Moscow time).

This round will be conducted according to ACM/ICPC rules. Therefore, solutions will be judged on all testcases during the competition.

The competition is not team-based, and you will be given 11 problems and 5 hours to solve them.

Please note that the penalty for submitting an incorrect answer in this competition is 20 minutes.

We are sorry that the problems are written in Chinese in this competition, but we will also provide English PDF statements.

All questions were created and written by beidiaodadejht, emplace_back, Huan_YP2002, kikcer, limithym, wjd_ and me.

We would like to thank:
1. MikeMirzayanov for creating Codeforces and Polygon.
2. CPC club of Southeast University and the seuOJ provided by SEUCPC club .
3. Science and Technology Association of Southeastern university school of Computer Science and Engineering, school of Software and school of Artificial Intelligence for all their works and all the staff involved in this contest.
4. Tobo, 2333_, zeemanz, Makabaka, robinyqc, HKing147, king_of_gamers, Ram_seu, YJWYYDS, huahua13 for testing this round and giving useful feedback.
5. FanRuan's sponsorship for the competition.
6. Last but not least, you for participating in this round.

Good luck and have fun!

Update: We are so sorry for the too difficult problems.

Update2: Editorial is up.

In problem 2028F - Alice's Adventures in Addition, when I hack other's code, the return verdict is "Unexpected verdict", can someone tells me why, thanks.

@applepi216

And this is my generator

#include<bits/stdc++.h>
using namespace std;
mt19937 rnd(233);
main()
{
	int t=1,n=2e5,m=1e4;
	cout<<t<<endl;
	cout<<n<<' '<<m<<endl;
	for(int i=1;i<=n;i++)
	{
		if(i==1||i==2)cout<<1;
		else if(i==n)cout<<int(1e4);
		else
		{
			if(rnd()%1000==0)cout<<0;
			else cout<<2;
		}
		cout<<" \n"[i==n];
	}
}

Hi, Codeforces!

We are so happy to invite you to participant in The 20th Southeast University Programming Contest (Summer), which will start at May/26/2024 09:00 (Moscow time).

This round will be conducted according to ACM/ICPC rules. Therefore, solutions will be judged on all test points during the competition.

The competition is team-based, with teams of 1 to 3 people, and you will be given 11 to 13 problems and 5 hours to solve them.

Please note that the penalty for submitting an incorrect answer in this competition is 20 minutes.

All questions were created and written by me and Ram_seu.

We would like to thank:
1. MikeMirzayanov for creating Codeforces and Polygon.
2. CPC club of Southeast University and the seuOJ provided by SEUCPC club .
3. Science and Technology Association of Southeastern university school of Computer Science and Engineering, school of Software and school of Artificial Intelligence for all their works and all the staff involved in this contest.
4. king_of_gamers,jackylova,Tobo,xukuan,thisislike_fan,CoffeeFish,9756 for testing this round and giving useful feedback.
5. Last but not least, You for participating in this round.

Good luck and have fun!

Update: editorial is up and you can see video tutorial here.

In this problem H. Tree Diameter 's tag, we could find its difficulty is 2000, but actually it is the last problem of a div1+div2 round. Is this a mistake?