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By YouKn0wWho, 3 days ago,

This post took $4$ years to make. And this is the most significant thing that I have ever shared in my whole life.

#### Story

Hi, I have been doing CP for like $4$ years and from the very beginning what I have been feeling is a need for a comprehensive topic list that will contain all sorts of topics from easy to advanced with corresponding tutorials, problem lists and templates so that I wouldn't have to look at different sites, from here to there. So what do you do when you think something is missing from the world? Yeah, you create that thing! So here I am, sharing the ultimate topic list that you will need in CP.

When I say that it took me $4$ years to make it, I genuinely mean it. I have been collecting them from the inception of my CP journey and yesterday I thought that it got its almost complete shape. You may not imagine the sheer excitement hidden under each of the characters of this post.

#### Payment

You can pay me just by upvoting this blog and by being a better programmer and human being than what you are right now.

I have added a few tutorials for each topic. You can also find more of them by just using your best companion — Google.

Added few problems for each topic. But you may notice that some of the topics don't have any problem attached. That's because under the attached tutorial section you will find lots of problems with that topic. If you want more problems, then you can do it just by using Google.

I have attached my template for each topic. You may not call it a template because some of them don't support the generalized use of the topic. But you can use them easily if you understand the topic and solve problems using that template.

Lastly, I tried to state the difficulty of each topic by numbers from $1$ to $3$ so that people can understand what are the best topics for them. The distribution is as follows: $1$ — Beginner, $2$ — Intermediate, and $3$ — Advanced.

#### Contribute

You can comment the topic names that you think are missing right now and I am pretty sure some links are broken, do point those out if you find some.

I really wanted to post this blog before I die. Seems like I managed to do that. It's funny that I had this constant fear of what if I die before sharing this blog with the world given that the amount of work I have given to create this is monstrous. But now I am so happy that I am alive at this moment.

#### Conclusion

The whole purpose of this project is to help you with this astounding journey of you trying to be better, trying to achieve the best of what you can imagine. Hope that my efforts won't go in vain. I am waiting to see you at the top of the building that you made by the bricks of your expectations. I am waiting to see you smile and to be happy. Don't forget to enjoy the journey and have fun while riding the boat.

Best wishes, my friend .

• +2921

By awoo, history, 26 hours ago, translation,

1574A - Regular Bracket Sequences

Idea: BledDest

Tutorial
Solution (BledDest)

1574B - Combinatorics Homework

Idea: BledDest

Tutorial
Solution (awoo)

1574C - Slay the Dragon

Idea: BledDest

Tutorial
Solution (Neon)

1574D - The Strongest Build

Idea: BledDest

Tutorial
Solution (awoo)

1574E - Coloring

Idea: Roms

Tutorial
Solution (Roms)

1574F - Occurrences

Idea: BledDest

Tutorial
Solution (BledDest)

• +92

By Geothermal, history, 17 hours ago,

Hi, Codeforces!

I'm writing to ask if there's any way Round #745 can be rescheduled in light of the conflict between the round and the ICPC World Finals Invitational Division. For those unaware, teams unable or unwilling to travel to Moscow to attend the 2020 ICPC World Finals in person are competing remotely on September 30th. The two competitions completely overlap: the WF Invitational Division begins 90 minutes before the Codeforces round starts and ends 90 minutes after the round ends.

For what it's worth, the clash affects a fairly sizable population of participants: a total of 57 teams are currently slated to compete in WF remotely, so this affects around 170 people. Moreover, as ICPC WF qualifiers, these people are particularly likely to benefit from access to Div. 1 rounds, which generally aren't all too common. Unfortunately, the series of dates surrounding the 30th are relatively packed with contests, but here are a few scheduling options that might make sense (i.e., as far as I'm aware no other contests are being held during the CF timeslot on these dates):

• Move CF Round #745 to Sunday, September 26th or Monday, September 27th
• Swap Rounds #744 and #745 (I think it's not a problem if a Div. 3 round clashes with WF, since very few WF participants are in Div. 3 anyway)
• Move Round #745 to between Sunday and Wednesday of the following week (October 3rd — 6th)

I think moving Round #745 to October 3rd may make the most the sense, given that holding the round on a weekend may make it easier for those interested to participate. That said, I'm open to other solutions (or to keeping the round on the 30th if need be, but for obvious reasons I'd prefer a different date!).

If anyone has thoughts or suggestions, feel free to share them below.

• +158

By galen_colin, 13 hours ago,

Oh no, another good youtuber lost to the algorithm...

And you'd be right. So on my journey to become a sellout, I've put out a video describing, in brief, the way I would find problems to practice on. It's designed as a short overview, with a more detailed description to follow. Video is here, just under 90 seconds in length.

Note that everything is my opinion — maybe you have other experiences and/or other opinions, and that's fine, do what works for you.

title

• +110

By abcdqwerty12345, history, 3 days ago,

• +69

By Asymmetry, 4 days ago,

Prepared by Asymmetry

Prepared by Asymmetry
Prepared by Markadiusz, 1-gon and Asymmetry
Prepared by Asymmetry

• +65

By Riaru_Covece, history, 22 hours ago,

I am new to CF, or if there's a better way to ask my questions or if I am violating any rules please do let me know.

• +47

By LinkinPony, history, 3 days ago,

Just a few hours ago, The 2021 ICPC Asia Regionals Online Contest (I) was held on https://pintia.cn/. This contest(and the next on 26th) will determine the WHOLE Asia-East Division‘s quota. And how fantastic(according to some coaches) of these problems in this online contest? I upload the statement on GDrive and you can preread it here: aec-online-i-2021.pdf

I should clarify something here: This contest doesn't have a clarification function, and some problems are from Huawei. Guess which they are!

Some fantastic part of problems

After Yinchuan Site's cheating, Shenyang Site's problem leaking, this is the third(maybe?) ridiculous and disgusting thing that happened in EC Division this year. I don't know what's organizer's purpose is, but our participants' enthusiasm and determination of Competitive Programming is not something you can trample.

• +414

By IHateDynamicProgramming, history, 10 hours ago,

Hello,

I want to ask for an idea to solve this problem:

Given N <= 10^9 and K <= 5. How many sets (a1, a2, ..., ak) that 1 <= a1 < a2 < a3 < ... < ak <= N and a1 + a2 + ... + ak = N?

For an example, with N = 10, K = 3, the result is 4: (1, 2, 7), (1, 3, 6), (1, 4, 5), (2, 3, 5).

Thanks!

• +12

By thanhchauns2, history, 2 months ago,

Or I will shave my hair.