The 17th round of the first Universal Cup is happening this week. The contest is based on the Final Contest of the China Collegiate Programming Contest (中国大学生程序设计竞赛, CCPC), which took place in Guangzhou on May 14th, 2023. Around 130 teams joined the on-site round.

Onsite Judges: amiya, Qingyu

Tasks Authors: amiya, djq_cpp, flowerletter, gyh20, ix35, Rebelz, Qingyu, Yakumo_Ran

Testers: AcFunction, changruinian2020, cnnfls_csy, Crystally, emptyhope, flowerletter, gyh20, He_Ren, Heltion, kgqy, llzer, loveye , lqx2005, MagicNiu, Mr_Eight, orzdevinwang, qazswedx2, rsy, Starch, sunzh, ttklwxx, wangziji, Z-301

As always, there are three time windows for you to join:

• May 20th 13:00 — 18:00 (UTC +8)
• May 20th 19:00 — 24:00 (UTC +8)
• May 21st 02:00 — 07:00 (UTC +8)

Please note that you can see two scoreboards in DOMjudge. The 'Local Scoreboard' shows the standings ONLY IN THE CURRENT TIME WINDOW. And the 'Combined Scoreboard' shows all participants, including the onsite participants, and the cup participants in the previous time windows.

Contest link: https://domjudge.qoj.ac/

Universal Cup Scoreboard: https://qoj.ac/ucup/scoreboard

About Universal Cup:

Universal Cup is a non-profit organization dedicated to providing trainings for competitive programming teams. Up to now, there are more than 600 teams from all over the world registering for Universal Cup.

A more detailed introduction: https://codeforces.com/blog/entry/111672

Register a new team: https://ucup.ac/register (the registration request will be processed before each stage)

Results of the past stages: https://ucup.ac/results

Terms: https://ucup.ac/terms

Ratings: https://ucup.ac/rating

Hello Codeforces! The 6th Stage of the 1st Universal Cup is coming. It will be held from Mar 4th to 5th.

The contest is based on an official ICPC Asia Pacific regional contest. It has been used in the 2022 ICPC Asia Taoyuan Regional Programming Contest, which was held on November 19, 2022 — November 21, 2022. Thanks to the judges and authors for preparing this great contest and sharing with us as a Universal Cup Stage.

As usual, we have three time windows for participating. You can participate in the contest in the following three time windows:

• Mar 4th 13:00 — 18:00 (UTC +8)
• Mar 4th 19:00 — 24:00 (UTC +8)
• Mar 5th 02:00 — 07:00 (UTC +8)

Please note that you can see two scoreboards in DOMjudge. The 'Local Scoreboard' shows the standings ONLY IN THE CURRENT TIME WINDOW. And the 'Combined Scoreboard' shows all participants, including the onsite participants, and the cup participants in the previous time windows.

Contest link: https://domjudge.qoj.ac/

Universal Cup Scoreboard: https://qoj.ac/ucup/scoreboard

About Universal Cup:

Universal Cup is a non-profit organization dedicated to providing trainings for competitive programming teams. Up to now, there are more than 500 teams from all over the world registering for Universal Cup.

A more detailed introduction: https://codeforces.com/blog/entry/111672

Register a new team: https://ucup.ac/register (the registration request will be processed before each stage)

Results of the past stages: https://ucup.ac/results

Terms: https://ucup.ac/terms

Ratings: https://ucup.ac/rating

Hello everyone! The 3rd Stage of the 1st Universal Cup: Poland, will be held on Feb 11th, 2023.

The contest was used in the Akademickie Mistrzostwa Polski w Programowaniu Zespołowym (AMPPZ) 2022, which was hosted by Jagiellonian University.

Authors: paladin, krismaz, Krzysztof Kleiner, Daniel Goc, Kasia, kpw29, Michał Woźny

Special thanks to kostka, who coordinated the contest and gave us a huge help for setting the problems to make it possible as a Universal Cup stage. And thanks to Lech Duraj, the head of the jury of the AMPPZ, provides the contest materials and helps us to use them.

The contest will start soon. You can participate in the contest in the following three time windows:

• Feb 11th 13:00 — 18:00 (UTC +8)
• Feb 11th 19:00 — 24:00 (UTC +8)
• Feb 12th 02:00 — 07:00 (UTC +8)

Please note that you can see two scoreboards in DOMjudge. The 'Local Scoreboard' shows the standings ONLY IN THE CURRENT TIME WINDOW. And the 'Combined Scoreboard' shows all participants, including the onsite participants, and the cup participants in the previous time windows.

Contest link: https://domjudge.qoj.ac/

Regional Scoreboard: https://amppz.tcs.uj.edu.pl/ranking/

Universal Cup Scoreboard: https://qoj.ac/ucup/scoreboard

About Universal Cup:

Universal Cup is a non-profit organization dedicated to providing trainings for competitive programming teams. Up to now, there are more than 200 teams from all over the world registering for Universal Cup.

A more detailed introduction: https://codeforces.com/blog/entry/111672

Register a new team: https://ucup.ac/register

How to solve task C and G?

Since I didn't find a place to discuss the CCO problems, I decided to post this blog.

How to solve Day 2 Problem 3 (Good Game)?

Let's discuss the problems here.

How to solve H. (Hoshi Sudoku) and I. (Imbalance)?

Let's discuss the tasks here.

How to solve problem B?

It seems that the Baltic Olympiad in Informatics (BOI) 2022 is taking place.

Since I didn't find any announcement, will there be a mirror contest this year?

Let's discuss problems here.

How did you solve problem L?

How to solve Problem 7, 10? Is there any tutorial available?

Could not find an official announcement, let's discuss problems here.

As we know, USACO is a competitive programming contest primarily for secondary school students in the US. It offers a large collection of excellent problems, from the easy to the difficult. Many of the problems are educational and worthwhile as training material.

However, the official website only offers problems from as early as 2011, and older problems are hard to find. Some of the Online Judges, such as POJ, contain some of the problems, but they are not properly filed together, and it's difficult to find the corresponding solution and test data.

In this post, I will try to list all the USACO materials that I have found so far. Most of the materials come from some old websites, and thanks to the efforts of web.archive.org, we can check out old websites that no longer exist. In addition, many of the problems were used as training materials in the training of Chinese IOI teams about 20 years ago. These materials have been preserved and are available through some Chinese websites.

It is important to note that since some of the materials are from a single source, I cannot confirm that the content is the original one. Also this list is not complete, there are still a lot materials I could not find. If anyone has these materials and would like to share it, please leave it in the comments section.

USACO 2021~2022

USACO 2020~2021

USACO 2019~2020

USACO 2018~2019

USACO 2017~2018

USACO 2016~2017

USACO 2015~2016

USACO 2014~2015

USACO 2013~2014

USACO 2012~2013

USACO 2011~2012

USACO 2010~2011

USACO 2009~2010

USACO 2008~2009

USACO 2007~2008

USACO 2006~2007

USACO 2005~2006

USACO 2004~2005

USACO 2003~2004

USACO 2002~2003

USACO 2001~2002

USACO 2000~2001

USACO 1999~2000

USACO 1998~1999

USACO 1997~1998

USACO 1996~1997

USACO 1992~1996

Let's discuss problems here.

The opentrains provides a series of high-quality ICPC training contests. However, its contest list is not complete(then it is difficult in finding some contests), and we cannot know if the contest has an editorial until we finish it. Therefore I made a list containing almost all of the contest materials, including contest id, statements, solutions and editorials. I don't know whether these materials can be made public (may affect their training value), so I only provided their corresponding links in opentrains in the table.

The link for Statements, Solutions and Editorials is in the format of http://opentrains.snarknews.info/~ejudge/index.cgi?solarc2=CONTEST_ID&sid=SESSION_ID. You can save the entire page and replace the field SID_HERE in the page with yours. Your SESSION_ID can be obtained from the URL that you jumped to after logging in at http://opentrains.snarknews.info.

For most of the Open Cup and Petrozavodsk contests, you can find the upsolve link in zimpha's posts(here and here). For other contests, I provided some upsolve links that do not require private logins.

You can find the list here, and I hope it will be helpful to you.

GP of Beijing is finished now. How to solve H(Nonsense) and I(Number Theory)?

How to solve B, H, K?