"Algorithms in Depth" Stream Series: Kicking Off With FFT Hi Codeforces! I’ve long believed that it's _really_ worth revisiting the same competitive programming topics multiple times. The first time, you’re just trying to survive and maybe grasp the basics. The second time, you’ve solved some problems, you know where you got confused, and you're ready to absorb more. By the third time, you’ve seen and solved enough to start appreciating the subtleties — the tricks, advanced applications, deeper meaning. But most lectures I’ve seen are designed as a one-size-fits-all — trying to cover everything from scratch _and_ dive into the advanced stuff in one go. That’s rarely optimal. Take binary search. I once talked about it for six hours straight. A beginner at that lecture would’ve probably quit CP immediately. And that’s ok. Beginners don’t need all that. But the truth is, there _is_ that much depth to explore even in seemingly simple topics like binary search — once you're ready. Yet many people only see the beginner version once and mo...

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Codeforces Round 987 (Div. 2) Editorial <spoiler summary="A little backstory about the round (ACGN)">The Highschool CPers (HSCP) Discord server was created in April 2022 by [user:pwned,2024-11-14], which over time grew into a close-knit community of highschool competitive programmers. I joined in the same month of its creation, and in the next month I approached [user:pwned,2024-11-14] about the possibility of setting a contest. Thus the HSCP round concept was born. Over the next month or so, the initial problems were born; the current problems A and F were produced in June-July 2022. We had several problem ideas by then, enough to set a div.2 round. However, as I was going to be busy in my 5th year of high school, and may not be that responsive to coordinators, the contest was in the ownership of [user:pwned,2024-11-14], who needed to wait until he reached master in order to propose the set on Codeforces. However, this step took almost 1.5 years as he would stay at candidate master for 57 consecutive contests, eve...

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I'm quitting CP for teaching! This year I started teaching a few friends which has scaled to a community of thousands of coders. We developed various resources this year like the ACD Ladders, Hard75 bot, ACD bot, and most importantly the ACD discord server (which now has more than 7k members-making it the biggest active Indian CP server!), the best part is all these resources are absolutely free! Thousands of coders use these resources on daily basis and have seen significant growth in their CP profiles, hundreds of students even got help in placements by these resources! The journey has been thrilling to say the least, I had never thought that we’d scale so much so quick and thanks a lot for all the support! [TL;DR: here's a ~6 mins video covering all of this: [here](https://youtu.be/GhouZ9M5S7g) ] However I resigned from Microsoft in September this year and joined a startup! The work is amazing to be honest! however the lack of bandwidth now doesn’t allow me to contribute much to teaching, I am not that act...

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Problemsetting Goal Since goals are very important in any individual's life, I decided to **set** a goal for myself. The target is to **set** 100 problems until I quit cp. Current progress: **40** | # | Date | <center>Problem</center> | <center>Contest</center> | <center>Difficulty</center> | Comments | Feedback | |----|---------------|----------------------------------------------------------------------------------------------|-----------------------------------------------------------------|-----------------------------------------------...

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I Reached GM after 5 years Hello Codeforces! I did it! My main goal for 2022 was to reach red and I succeeded in the last contest of the year by getting +1 delta and going from cursed 2399 to 2400! I was very happy but scared to celebrate because I was worried that my rating would go down to 2399 again after the cheater removal. But now it’s 2401, so I think I’m safe now. Why am I writing this blog? I'm very excited about this achievement, it means a lot to me and I want to share my happiness with Codeforces. Also people ask me in DM quite often about how I got onto this level or who I am in general, so I think it's time to summarize it all into one blog post. Oh, wait… You don’t even know me, so why should you keep reading this blog post? Let me introduce myself a little first. I’m a high schooler from a small European country where few people do Codeforces. I love competing in OI and MO, I always did. One day, my father found the Codeforces website and suggested that I should start practicing there. At ...

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FAQ, Advice & AMA This post assumes you're super ambitious. But don't take any advice too seriously -- we're all different. This is simply what worked for me and might work for you. Choose your own path. #### Useful Links - [LI2 Contests](https://codeforces.me/blog/entry/131164) -- used this course when I was starting out. - [usaco.guide](usaco.guide) -- a collection of great articles & problems on almost all topics. - [OI Checklist](https://docs.google.com/spreadsheets/d/15b1ZaP1owTfTcA4vQ69A5S_wUd_vJmM8Slwu6FiWgP4/edit?usp=sharing) -- my OI Checklist. - [Pavel Mavrin's youtube channel](https://www.youtube.com/channel/UC9WDkCyUlNTncq1Y-mFSgLQ) -- watched his great lectures when I was younger :) - [qoj.ac](qoj.ac), [loj.ac](loj.ac), [dmoj.ca](dmoj.ca), [oj.uz](dmoj.ca), ... #### How do I start? **Advice:** join a great community (school, club, ...), try solving problems, and find someone who can answer your silly questions. I wouldn't have started CP if not for my school. Of c...

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My First Blog — Why Understanding Psychology and Philosophy is Good for CP (This is a shitpost. There is no scientific evidence for what I say. You shall not take it seriously.) As a matter of fact, psychology is a magic for tracking our minds. Most people don't understand why they lose their temper when they are offended, but I do. That's why I always understand why I want to f*** someone. For two apparent reasons, I shall claim that psychology helps with CP: 1. It helps you to know your thinking better. Yes, but, even if you don't formally know psychology, maybe you are already aware of your thinking process. However, there are a lot of numb nerds who never pay attention to their minds, so it's necessary for them to take a dose of psychology. After all, your brain is your weapon. If you use your weapon without knowing its mechanism, how are you going to maximize its efficiency? It's almost like using Windows operating system for 20 years without knowing how to ctrl+C and ctrl+V. You are wasting your talent. Also you can't pride yourself for knowing a...

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Have you regretted quitting competitive programming? I began to learn about CP during the last quarter of my first year at college through the CP community at our university. I created an account on Codeforces and attempted to solve random problems, often aiming for higher rating problems to prove to myself that I was skilled. I wasn't following any strategy, and there was no one to guide me. I simply pick random problems with ratings higher than my actual skill level and try to solve them even if it takes me days to do it. I managed to reach a Specialist with no knowledge. and after gaining some random knowledge in various topics, I stopped training and CP for almost a year, barely solving problems when I was bored. Now, I realized all my mistakes and understand that I wasn't actually training; I was simply wasting my time. The issue I'm facing now is that I'm in my third year at college, and in my country "Egypt", passing a job interview requires more than just problem solving you also need to know abo...

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I Competed Everyday for a Month Hello, codeforces community! This is a follow up to the blog, [Competing Everyday?](https://codeforces.me/blog/entry/82778). This may sound like a flex but the point is to help the Pupils and Newbies who are stuck with their rating. I had been struggling to get to Specialist level for a half a year despite solving CP problems almost everyday. It got very frustrating to the point that I almost quit. Fortunately, in October I got some free time and I thought to change my strategy. I noticed that my rating depends on the problems which I can solve during the contests (roughly speaking), so why do not I practice contests instead of individual problems. To further check this line of reasoning I asked the same thing in the previous blog. A couple of high rated coders shared that they used the same strategy. As you can see in my rating graph, I went from a Newbie to an Expert now (Hopefully it stays like that XD), that too in less than a month. <spoiler summary="The Method I...

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A Christmas Gift for CP: CodeMentor ## CodeMentor: Your AI-Powered Companion for Competitive Programming Hi Codeforces! I'm excited to share **CodeMentor** &mdash; a Chrome extension I built that gives you progressive AI hints and explanations when you're stuck on problems, without spoiling the solution. It's designed to help you learn and grow, whether you're practicing for contests or preparing for interviews. ## What It Does **For Codeforces & CodeChef (Competitive Programming):** Get progressive hints to improve your CP skills without spoiling solutions. Perfect for when you're stuck during practice or want to understand a problem better after a contest. **For LeetCode (Interview Preparation):** Get detailed explanations and hints to understand problems better for technical interviews. Learn problem-solving patterns and approaches that interviewers look for. --- ## Features That Will Help You ### Progressive AI Hints & Explanations **The Problem:** You're stuck on a problem. You've been sta...

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Infoleague Spring 2022 Round Editorial <spoiler summary="Vote your favourite problem"> <spoiler summary="Div 2"> Div 2A &mdash; The Hatchet Div 2B &mdash; Floor Or Xor Div 2C &mdash; Yet Another Constructive Problem Didn't participate, idc </spoiler> <spoiler summary="Div 1"> Div 1A &mdash; Bamboo Coloring Div 1B &mdash; Xor Or Floor Div 1C &mdash; Jump Didn't participate, idc </spoiler> </spoiler> [103633A &mdash; The Hatchet](https://codeforces.me/gym/103633/problem/A) ------------------ Author: [user:tibinyte,2022-03-30] <spoiler summary="Rate Problem"> 1700 or less 1800 1900 2000 2100 or more Didn't solve it, idk </spoiler> <spoiler summary="Solution"> ### Subtask 1 : $N \le 10^2$ This subta...

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Goodbye CP. Today, I finished my last CP contest &mdash; NOIP 2024 in China. I will be leaving CP, and of course, Codeforces and other coding websites. I know that some CF users may downvote this when they see that I'm only a pupil here. But since I'm leaving, I will not care about my contribution anymore. In fact I never cared about it even when one of my comments got 15 downvotes. You can see from my CF rating(1385) and my AtCoder Rating(1546) that I am only a noob. Once I only passed 5 out of all the 7 problems in a CF div4. I just know nothing about number theory and things like that. I can't even remember some basic algorithms like Tarjan's algorithm. I have a feeling that my coding ability is always going down. But that is not the main reason why I quit CP. I started learning coding 6 years ago, and began on my way of CP in January 2021, because I was interested in computers and of course, coding. Before the spring of 2024, everything was fine. I spent a lot of time on coding classe...

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[Archive] My Father is Ratist **UPD 26/10/2023**: I find this blog very funny and a very relatable pasta for some of us, so rather than archiving it, I'll just post this. By the way, please to all the people out there. Don't feel like practicing CP a burden. It's something you should enjoy, and if you don't please quit. My relationship with my father doesn't get any better since I've posted this two years ago. But at least now that I'm turning 21 makes my brain a bit more considerate to people. --- Hi everyone. Competitive programming is an entertaining activity. I love it, and it really helps me even in my daily university courses I had. I've been doing CP for 5 years (well, I had breaks in between and other stuff to do and study besides doing cp). This post is not a rant or a "hello sir, can you help me improve in cp"-type of post. I just wanna share some story that makes me sad. But don't feel pity for me and say I'm a crybaby and I should get good. I'm in catch with my goal and trying my best. I don...

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What if a Nutella goes rogue? Many of us are worried about AIs becoming smarter than humans at algorithmic tasks and ending online sport programming as we know it, very few of us however consider an equally devastating threat that already exists, but hasn't affected anyone yet (until today, sorry div3 paralympians) &mdash; The Rogue Nutella. Think of the following scenario- A random nutella wakes up one day and decides that online sport programming must end. His motivations for this? Irrelevant (most probably a painful breakup with his 2d anime waifu, or annoyance at seeing the 1e9'th (aa + bb)(a + b) problem on a competitive programming website). So, he thinks for not very long and comes up with a brilliant idea which would trivialise all contests- He creates an anonymous youtube channel and decides to livestream himself solving codeforces rounds (whilst maintaining anonymity of course). What happens next? Armageddon. Immediately, all rounds become speedforces for people to copy code from his stream and...

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Are we necromancers for enjoying a dead thing? I’ve been seeing many people I know talking about how LLMs have "killed" CP. People are getting frustrated seeing leaderboards, and asking what is even the point now. Lets take a close example: **Chess after Deep Blue:** In 1997, IBM's Deep Blue beat Garry Kasparov. It was a very shocking to those chess players (first such major AI like event ig), there was also similar discussion if chess was dead then as well. Today, any free chess engine on your phone can obliterate the reigning World Champion. After soo many years did chess really die? No, it became popular than ever. Why? Because humans don't play chess to prove they are better than Chess engines. We play to beat the other guys, and more importantly, better than we were yesterday. CP is following the exact same trajectory. The Harsh Truth: Online CP is a Gym, Not a Stadium Let's not sugarcoat it: Online CP, as a perfectly fair competitive arena, is effectively dead. With the current state of AI, online rounds are infe...

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7 Types of Codeforces Users Salam Codeforces! Salam Codeforces! Salam Codeforces! Today I will tell you 7 types of coders. ### The "I'll Upsolve Later" Joins contests, reads problem A, nods wisely, then disappears. "I’ll solve it later." (No, he won’t.) ### The Debugging Monk Writes code in 5 mins, spends 90 mins debugging, adds 27 cout statements, still WA. "Codeforces is broken." (No, your logic is.) ### The Math God Solves problem D using a formula no one understands. Thinks segment trees are too basic. Probably discovered a new theorem mid-contest. ### The Python Wizard Writes a 3-line solution that gets TLE on test 2. "Codeforces is biased against Python users!" (Or maybe input() is just slow.) ### The Grandmaster Solves E before you finish reading problem A. Uses one-letter variable names but writes cleaner code than your CS professor. Might be a bot. ### The Memelord Never competes, just comments “bruh” on blogs. Owns a shrine of tourist’s submissions. "Rat...

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Useless CP Information #6: How Much Harder is Div 1 vs Div 2? Hey guys it's your favorite <strike>purple</strike> not anymore CF shitposter here. We're back to hopefully non-controversial useless information lol I think anecdotally we all have this gut feeling that it's harder to get a X perf in a div 2 than a div 3, and in turn harder to get X perf in a div 1 than a div 2. Is this urban legend or a real phenomenon? Methodology ------------------ I took several of the most recent separated div 1 and div 2 rounds where the div 1 round has the same problems shifted by 2 positions. For each contestant in the div 2 round, we'll: - Calculate and record their div 2 perf - Convert to estimated div 1 score by dropping problem A/B, adjusting timestamps on the rest of the problems, and recalculating the score based on the problem values for div 1. (We will discard anyone who solves C/D/E/F before A/B) - Calculate and record their div 1 perf from the new score we calculate. ### Calculating performance (CP lesson time!) Using FFT, our...

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Why Is It So Hard to Consider Yourself "Good" at Competitive Programming? When I ask someone how good they are at chess, the response I get most often by far is "I'm decent." How decent? Well, from my experience, it ranges anywhere from 600 rated, a below average chess.com player, to 2400 rated, nearly a master level player. Almost no one ever says they are "good" at chess. To me, Competitive Programming seems to be similar. So what is "good" in competitive programming. And why is it so hard to consider yourself good? Now statistically, the vast majority of Codeforces accounts are Newbies with ratings below 1200. Div 3 and Div 2 contests have tons of them, solving only 1 or 2 problems. But does that make a pupil "decent," or even "good?" There's a reason most people won't be satisfied with that conclusion: a lot of these newbies have yet to put in serious effort. Of course, some have, but many are simply normal college students who wanted to try it out for fun. Lets go back to chess. If a 600 ELO chess player go to a random city and start picking out ra...

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Petition to change strict handle rules The Current rules to change your handle to one that is already taken is <spoiler summary="Rules"> Again, this year if you took part in at least 10 rounds you can request a handle of an inactive participant. It means that the participant should have a period of activity on Codeforces of at most 180 days, this period should be in 2020 or earlier. The inactive participant can't have posted comments, messages, and so on. It can't take part in more than 2 contests. It will be automatically renamed and informed by email. A user has the opportunity to request back his/her handle: in this case, we will roll back the change and return your previous handle to you. If you can't change your handle to another, it means that some requirements don't meet. </spoiler> But if an account has been inactive for over 10 years why should the same set of rules apply? like someone who has participated in 3 contests and has been inactive for 14 years, what is the chance that he'll get back to the platf...

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Backtracking:the essential part of dynamic programming This is going to be my last blog in codeforces as i am going to quit doing competitive programming.I feel tired of doing it and i figure out i can't stand seeing some people that "worship" cp as their god or something.They only grind and grind without having a life.As the one that is busy nowadays i am unable to keep up with them.So i decided to share about my thoughts on why people don't seem to understand dp quite well.I mean,by making this blog it will enhance my IELTS writing ability and also my knowledge won't go to waste. Speaking of dynamic programming,we tend to know only some stuff such as recursion and memoization.This is true.However,we can't understand the meaning of dp without knowing a particular topic beforehand,backtracking. What is backtracking? backtracking is a to get an answer on a specific condition using the previous ones.There are a few conditions to allow backtracking to be executed.This is the reason why dp exists.I will mention them below: 1.There sho...

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How to Survive the CP Wall: Overcoming Frustration and Silencing Self-Hate #### We have all been there. You look at a problem, It looks simple. You spend 30 minutes typing, tweaking variables, and hitting compile. "Wrong Answer on Test 3." "Time Limit Exceeded." Suddenly, the voice in your head starts. “Why can’t I do this? Am I stupid? Maybe I’m just not built for competitive programming.” Stop right there. Let’s talk about how to stop hating yourself and how to break out of that dark mental loop. _1. Separate Your Rating From Your Self-Worth. Your Codeforces rating is not an IQ test. It is a measurement of practice hours and muscle memory. The Trap: Looking at Grandmasters and thinking you are a failure because you aren't green or blue yet. The Reality: They were stuck exactly where you are now. They just didn't quit. The Rule: A bad contest doesn’t mean you are bad. It just means your code had a bug. Fix the bug, separate yourself from the screen, and move on._ _2. Put Down the Keyboard (The 20-Minute Rule) When frustration hits, your brain g...

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Sniping Cheaters Episode 2: A Philosophical Rant Sniping Cheaters Episode 2: A Philosophical Rant ================== Background/Context: ------------------ After posting a bunch of these CF blogs, many people in my university discord asked me to leave and quit CP (since I allegedly used LLM's during contests -- if I did why am I still green). Now that I have qualified for the ICPC ECNA (regional contest) twice in a row, I want people to understand that I have never cheated on this account since the start of my journey in college. Finally, I really don't care if a lot of people on this platform used AI on the contests, if I lose rating because I couldn't solve a problem, then I view that as a personal **SKILL ISSUE**. Why should one bother doing competitive programming? ---------------------------------------------------- 1. To get cracked at coding interviews 2. Understand basic programming ball knowledge 3. Improve problem solving skills through pattern recognition ### The hard truth Codeforces rating is just a ...

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Why Most Beginners Quit CP So Early Why Most Beginners Quit Competitive Programming After 3 Months I've noticed something interesting over the years. Every semester, many students start competitive programming with a lot of excitement. They create a Codeforces account, solve a few easy problems, participate in contests, and dream of becoming a strong coder. But after 2-3 months, most of them disappear. Why? I think the biggest reason is expectations. Many beginners think they'll see rapid improvement if they solve enough problems. But CP doesn't work that way. Sometimes you practice for weeks and still perform badly in contests. Sometimes your rating drops even though you're working hard. Another common mistake is comparing yourself to others. You solve two problems and feel happy, then you check the standings and see someone your age solved everything. Suddenly, your progress doesn't feel good enough. Motivation is also a factor. In the beginning, every AC feels exciting. Later, you start getting...

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Group tutoring Hi. I offer classes for groups of 2-3 students. I teach competitive programming with a focus on problem-solving. There won't be many lectures because I can send you an article/video link instead. The lesson cycle is usually: I choose a problem, you say your thoughts and ideas, I comment on incorrect ideas, and we talk about the valid solution(s), possibly with drawings and pseudocode. In beginner groups, I might ask you to implement something, C++ or Python preferred. There's a lot of homework and you're expected to practice a few hours per week. We might spend half a lesson talking about 1-2 homework problems from last week. This is intended. We use Google Meet, shared whiteboard, and a collaborative editor Codebunk. After a lesson, you get a video recording and a codebunk with code/text history like this one https://codebunk.com/pb/3501100331621/. This allows you to copy links and code easily. There's a Discord group chat to ask questions between classes. - 1.5h les...

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You can do it, too! Introduction ------------------------------- So, I set myself [that challenge](https://codeforces.me/blog/entry/81383) to retire as a red coder before 24.09.2020... and I failed **miserably**. At least I am less delayed than most civil infrastructure projects. This blog will be a recap of this _short_ challenge with a mixture of some tips on practicing (for all levels!), some random life advice and, of course my bad sense of humour. It is dedicated to all those who aren't wonderkids, go from failure to failure and feel like banging their head into a wall during most of their competitive programming journey. Whatever your goal is, I'd like to strengthen your beliefs &mdash; you can do it! How it all started ------------------ My skill level has been in constant stagnation for years. I've always thought that I'm just not talented enough to be a grandmaster. Although I've been red twice in the past, it was quite lucky and the next contests were solid $-137$ and $-189$ so th...

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Scored 100/100 in Mathematics in 12th Class and still sucked at CP ! Yeah **I scored 100/100 in Mathematics** in my class 12th ISC board and anyone from India will know how easy/hard it is to get that score. But when I entered in CP and solve some codeforces question **I sucked**. I mean solving even a 1000 rated problem became a struggle for, and even I never heard of word like parity I just was like odd and even but not parity. Within some months I realise it was not DSA that I was lacking, it was pure mathematics because during my enitre school journey I never learnt how to proof my own formulas or how to contradict my guess to reach an optimal state. So i did what any normal math person will do &mdash; I learnt it. In my college I solved 9 to 10th class level olympiad questions and followed two books Mathematics Circles and Problem Solving strategies by Arther Engel. As I was already good at maths it took me few weeks to understand it and some months to really grasp it. Also solving previous year INMO previous years paper helped me a lot. N...

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Busy but Master #1 Alternative name: "Road to Master when you don't have time". Episode 1: August 2024 ### Preface I used to be a competitive programmer since ~8th grade. When covid started and we all had more time to solve problems, I actually began to see some progress in cp. I have two bronzes in the UOI (1 place to silver x2, sad). That's not too bad, and I probably don't regret it (though if I could go back, I'd definitely change my attitude). I always had one milestone: to become a Master (yellow) on Codeforces. As you can see, my max rating is 3 points below Master. Pretty sad. I need to fix that. But a few things happened compared to 2020: 1. 4 years have passed. 2. I'm in my last year of university. 3. I have a swe job. So, I definitely have much less free time than I did in 2020. This is probably the last period in my life when I have at least some time to improve in cp, and I need to use it mindfully and close all my competitive programming goals (that are still achievable)...

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I solved more than 1341 problems till difficulty 2200 but no improvement at all , I feel frustrated should I quit? Hello CF community I have been doing cp for 3 years,I solved more than 1341 problems ,but I'm still specialist,I'm really frustrated and I feel that I'm mentally retarted,many of my friends who started with me at the same time are masters and candidates now. Every time I fall down,I summon my strength and fight again,every 10 days I create a marathon on vjudge containings problems with specific difficulty(current one is 2200) and solve them.  I solved many problems ,and tried many strategies:solving easy problems,hard problems,virtual participation and upsolving but all this hard work was in vain .I'm not smart like others but I'm proud of being a hard worker . So guys you have the statement,any accepted solution please! (sorry for the very poor english)

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Perhaps you should wait a little before giving up... Seeing the [latest blog](https://codeforces.me/blog/entry/118674) by [user:WeaponizedAutist,2023-08-11], I think I can help those greys and greens by helping them test themselves if they should really give up. I am a 3rd year Computer Science and Engineering Student. I never took CP too seriously. But since placements and internships are approaching, I must catch up and become a bit serious towards it. - At the time of publishing this blog: I am rated **1359 at 107 problems**. - By the end of 3 months (When I will publish the sequel to this blog): I aim to reach a **stable 1600+ rating** (By stable I mean, it shouldn't be peak, I must have a non-decreasing graph around 1600s), and around **350+ problems** with utmost consistency (Seems doable). Point to be noted: I am quite a **procrastinator**, and end up giving up midway most of the times (You can see that by my current codeforces problems heatmap below). Perhaps, I think it's about psychology, I don't consider stuff too...

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WHAT HAPPENED IN Educational Codeforces Round 181 [Rated for Div. 2]? **How does D already have 4k submissions?** ====================================================================================================================== **How does C have 12k submissions (with 10 minutes left in the contest)?** ====================================================================================================================== I thought I was having a good contest, So I stayed in the zone, and didn’t check the standings. After submitting D, I finally saw the standings — and I am shocked I am wondering about quitting CP altogether at this point. I miss the days when solving up to C roughly meant Expert-level performance… …and solving up to D was around Candidate Master-level. Have I genuinely become bad at programming? Or is there something else going on?

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Help me to reach 1900 please I joined CP for about 2 years ago (more than 16 months ago, I had another account with cringe nickname and I didn't want to wait a lot to change, so sorry codeforces, I don't use it anymore, but whatever), in old account I managed to reach 1400 in 3.5 months and get 1600 from 1400 in 2 more months. However, after that my progress got stuck and since that my rating changed very and very slow (the only notable change was quick reaching 1880 and getting back to 1600 as fast as reaching it). I joined a free online course (from Yandex), where I learned a lot of algos, but not the ways on how to use it. I tried to be the best at the courses, solving as many problems and spending as much time as I can; I solved a lot of problems here, but when I faced real problems, like in CF or at nationwide olympiads/contests, I had really no clue what to do. I was so upset so I quitted the course at a middle of the path and a little bit later I quitted CP at all. The only successful contest for me was ...

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[Journaling Blog] Reaching 1600+ by March end The purpose of this blog is to plan and work towards achieving the goal of reaching 1625/Expert (currently at 1125, a gap of exactly 500 points) by the end of March. While there's no compulsion or ultimatum to quit CP if the goal isn't met, I aim to approach it as a challenge to solve. So, plan is to approach the problem using agile methodology, as it will provide framework to guide my progress. The key points, according to my understanding of the Agile mindset: 1. Sprint Planning: For me, this will involve planning tasks or problems to solve every two weeks. 2. Regular Standups: Since daily standups won't be much useful, I will reflect on progress weekly and share updates in this blog. Questions to answer each week: - What accomplished? (in terms of rating points and the range of problems solved) - What will I work on next week? - Any blockers or challenges? (I’ll reflect on it) Quick calculation: Need to gain 500 rating points in 3 months, an average of ~167 poi...

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The Hidden Inequality in Competitive Programming The Hidden Inequality in Competitive Programming: Why CP Is Not Global Yet Competitive Programming (CP) is often celebrated as a meritocratic, borderless arena where anyone with a laptop and an internet connection can rise to the top. But beneath the surface, there’s a reality we rarely discuss: **CP is not a level playing field, and it’s far from truly global.** Awareness: The First Barrier In some countries—Russia, China, Poland, and a handful of others—CP is a well-known, even prestigious pursuit. Students are introduced to Olympiad math and programming early, and there are established school clubs, training camps, and experienced mentors. By university, many have years of CP exposure. But for most of the world, CP is invisible: - It’s not taught in schools. - There are no local contests, clubs, or teachers. - Most students discover CP by accident, often late—maybe while prepping for interviews or stumbling on a YouTube video. Result: Many talented minds never ...

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[Consistency] Finding Motivation Hello, CodeForces! Recently, one of my students had a really bad contest. Even though he worked really hard in the last couple months, he could not pass an important qualifying round of an arguably easy, new, Romanian contest. The first 4 'official' contestants qualified, and sadly he was the fifth. He was really upset after the contest, and had a hard time gathering enough motivation/discipline to continue working, because there were scenarios in his head such as "what if this will happen in training camp?" or "what not passing had a really bad turn on my future?" Today, I am going to share with you all a simple method that can help you get over a bad contest or just motivate you to work more in general. Keep in mind, I am not a specialist in this domain, I am only a teacher with experience, so there might be better methods out there, but throughout the years I have seen that what you are about to read worked best on many of the my students. I advise you to also read this great ...

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What is DP,seriously This will most likely be my last blog about dp since i have given up on cp communities.noone is helping me nor even caring to me.whenever i ask someone they think im just trolling when im being dead serious. dynamic programming,what is it? dynamic programming is the technique of optimization.instead of bruteforcing,we can just do dp.which is convenient.there are 2 ways.recursion with memoization and filling arrays(basically all memoization). sounds simple right? lets move on to the example.there are alot of classical dp problems like 0-1 knapsack,prefix sum,catalan numbers and so on.it might be hard if u do them for the first time.but as time goes on,it will become easier. now to the real deal.how to do it in contest when its not classical problems.like modified knapsack wheremaybe 1 item cannot be taken twice or maybe every i-th taking process some value will cut down into n/2 because of some reason and many more.now you are solving a brand new problems.can you? this is...

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Learning... **Note for anyone else reading this:** I’m not on social media. I don't write publicly. I wrote this here only so my future self can come back and read it one day. This is for me, not for validation. This is my first and last blog. So you can skip and if I have option to hide it I'll hide it. Today at 03:48 AM I’m writing this only for myself. I’m at a point where I need to record what I was thinking, what I believed, and how things actually turned out so that in the future I don’t lie to myself about this phase. I moved through Div4 problems, then Div3 problems while practicing. I solved around 300 problems. Offline, without pressure, things felt good. I could solve B, C, sometimes D. I started looking at other people’s rating graphs clean, exponential rises. Somewhere inside, I assumed mine would look similar if I just worked hard enough. I planned everything in my head. Give Div3. Solve a few problems. Get a good rank. Build confidence. Keep growing. I took this...

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The Toxic Mindset in Competitive Programming and How to Fight It #### Introduction Rating is a great measure of skill and a nice way to observe progress by comparing yourself to your past self and seeing where you stand in the community. As great measure as it is, there are a lot of problems that come with it. They have nothing to do with how the rating system works but rather with how human beings function. In this blog post, I will talk about some of the most pressing personal problems that come up with rating and try to provide some advice on how to solve them, speaking from personal experience and from the experience of a lot of other people I know. #### Associating self-worth to rating This is, in my opinion, the most significant problem people face, and it also pretty much contains all the following problems as a subset. It's extremely easy to fall into this rabbit hole since, as a competitive programmer, it only feels natural to associate our rating with intelligence and, respectively, our intelligence with self-worth. Why is this su...

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Got sick after training for CP.What to do? So i decided to do a gimme 1500-1900 on discord after failing on an edu round (i hate edu rounds and from now on i swear that i won't join any edu rounds).i was trying to solve this [problem](https://codeforces.me/problemset/problem/1660/d).i tried to solve that problem but it took me 9 hours to AC it.At first i was really happy about it and felt fine.Although a few minutes later,i started to feel dizzy and i had a diarrhea.The next day,i had a fever,nausea,and severe diarrhea.I puked twice and could not eat lunch as much as i usually do.I thought that 9 hours training for just 1 day would be fine until i got sick (i saw some stories on IOI camp and they said that they did intense trainings.They were fine during the process) Does anyone have any tips to help me do CP training without getting sick? (i was planning to quit cp for at least a month but i don't know if that is wise)

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10 Things Only Codeforces Users Will Understand **If you've spent time on Codeforces, you've probably experienced these:** 1. Submitting and praying it’s not Wrong ans on test 2. 2. Thinking you've solved problem C, but it’s TLE. 3. Seeing "Pretests Passed" and celebrating too early. 4. Getting a hack in Educational Round and feeling like a genius. 5. Copy-pasting someone’s template and not understanding half of it. 6. Checking rating updates like it’s stock market news. 7. Getting -100 in a contest and swearing you’ll quit CP (but never do). 8. Seeing Div 1 problems and wondering if they are even real. 9. Hoping for an easy A but getting an implementation nightmare. 10. Saying “just one more problem” and then realizing it’s 3 AM. **Which ones do you relate to? Drop your favorite Codeforces moment in the comments!**

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Bro wanna cook SUNDARSTEM, really? (Cheater spotted) I just wanna make sure that I'm not a 100% sure already but I've a strong suspicion. You people can look at my suspicions below. Its about [user:ItsTimeToCookSundarSTEM,2025-08-09]. Bro took an institute's name which is quiet frankly the best CP institute here in Pakistan. (All 4 IOI members have been from there in both years of our participation with 6 medals) Bro became a CM in 10 contests which is in itself quite shocking given the CP culture and awareness here in Pakistan.  You can probably see how shocking his contest history is already. His first contest was an adhoc heavy contest. The Gellyfish one and he failed there badly. I guess, we all know that GPT sucks on problems of those sort. Even there, if you go look at his submissions for A. Well, first look at the order. He submitted A for some times and then tried B, then got accepted on A. All that in 35 minutes from the beginning of the contest...

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I am thinking to quit Codeforces I have been highly motivated and energetic to do my Codeforces practice since I started two months back. I was quite happy with my progress. But for some reason, my performance is constantly decreasing over the past one week. Just to give the perspective, few weeks back I was quite comfortable in solving 1600 difficulty level problems, and now I am failing repeatedly for 1000-1100 level problems. I am so much demotivated by this. I don't know if I have attained my saturation point. This is so depressing and disheartening. I had created so much of dreams around competitive programming, I was dreaming to join Google someday by developing extraordinary CP skills, I was so passionate and determined, but never thought I would fall apart this soon. It is so disheartening to say goodbye to the goal, that kept you awake in nights almost every day for last two months, I really don't want to quit this, but I can't watch myself failing so miserably. May be only this much of the part was in my ...

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How to quit procrastinating and start grinding on cp problems Yibo and I put together an in depth video on what procrastination in cp looks like and tips on how to avoid procrastinating. You can check the video out here: [https://www.youtube.com/watch?v=yDjCh1i_LnQ](https://www.youtube.com/watch?v=yDjCh1i_LnQ)

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My strategy for ZCO 2027! Hello Codeforces, ================= I like to code. Entered CP in late 2026; I almost quit cuz it was too hard, but the stuff that's hard is always good. Looking forward to participating in the Zonal Computing Olympiad (ZCO), the first stage for the **Indian Computing Olympiad (ICO)**. Missing out on ZCO-2026 was a big shame for me, so I want to qualify in the upcoming year. ### The Strat The exam is held on CodeChef, so I'll start practising more there (forgive me, Mike) and, at the same time, write these blog posts to keep going! - using the CSES problem set - solving 1100- to 1300-rated CF problems (cuz for some reason these are just better structured) - solving 1400- to 1500-rated CC problems - fixing my contribution on CF (it's $ -25 $ ) Simple as that. _ZCO Blog 1 done!_

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From Math Equations to Code Hi Codeforces, I’ve been part of the CP community for about three months now. Before diving into this world, I spent a significant amount of time in Mathematics Olympiads. However, despite the effort, I couldn't achieve the results I aimed for, and eventually, the purely theoretical nature of competitive math started to feel stagnant. I transitioned to Competitive Programming looking for something more dynamic. What I realized quickly is that while math provides the foundation, CP requires a completely different level of logical rigor and optimization. You can't just find a solution; you must find the most efficient one. Transitioning from O(1) mathematical formulas to O(N \log N) or O(N) algorithmic implementations has been both challenging and refreshing. I am currently focused on mastering fundamental data structures and improving my implementation speed. My goal is to break out of the beginner ranks and reach a level where my logic can withstand the toughest test cases. Th...

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Need your advice!! Not able to solve Problem A and B(Specifically maths tagged problems) Hi, I started doing CP few months back. i am facing issues while solving A and B problems. Usually i crack the logic if problem is implementation based , but when its a maths problem, its become next to impossible for me to solve that problem. i need some advices from you guys , if you faced these same issues in the beginning of your journey then please let me know how you handeled this. sometimes a thought comes into my mind that i should quit CP as i think my IQ is very low!!

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Divide and conquer. Dynamic connectivity offline and DP optimization. Divide and conquer by queries. Hello, Codeforces! I have wanted to write an educational blog for a long time, but I couldn't find a topic for it. And recently I remembered that Codeforces doesn't have a good blog on one of my favorite topics: the "divide and conquer" technique. So I want to talk about it. The outline will be something like this: 1) Divide and conquer. What this technique is and what it is for. Example. 2) Dynamic connectivity offline with divide and conquer. Divide and conquer dp optimization. 3) Let me tell you about a method I invented myself: divide and conquer by queries. In this case, we divide not only the array, but also the queries into groups. So, here we go. First, about what this technique is. The point is about the following: let's say we have an array. Then, if we know how to calculate the answer for two parts of it, and if we know how to get the answer for the whole array from the answers of two parts, we can apply the divide and conquer technique. Let me show you the si...

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Take break in cp and now even problem A not able to solve. Hello Guys, I am doing cp for 6 month past and at that time i solved 200+ problem and at that time i am able to solve 1400-1500 level question after some emergency i quit cp and since last month i start again and not able to think solution of Problem A. I am also in 3rd year starting(India &mdash; CSE). So how can i come back? Where should i do practice? also in some last day, i felt fear to give contest because i am not able to or some time solve only A question in long time. Please give some advice how can i move on of this problem. ps: this is not my real id :)

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CP Rap Name After temporarily quitting competitive programming once I made USACO Plat I started making music, but unfortunately my label I signed with has asked me to change my name from DreamR (too basic). I'm thinking of changing the name to something code related. If you know of any cool-sounding cp words please let me know here lol. So far I have words like vim and terminal. Thanks.

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Ten Years of Competitive Programming 5 Hey, Codeforces! I’m AmirReza PourAkhavan, the former Codeforces Contest Coordinator. I let the story become complete, and I’m sharing it now. The story is about a 16-year-old competitive programmer who left his family and migrated to another city alone to follow competitive programming. After seven years, he advanced to the International Collegiate Programming Contest World Finals twice. Read the previous parts: [1](https://codeforces.me/blog/entry/107465), [2](https://codeforces.me/blog/entry/108838), [3](https://codeforces.me/blog/entry/114356), [4](https://codeforces.me/blog/entry/122483). **Read the Persian version** [**here**](https://docs.google.com/document/d/1TN8pnS_8te7MLDYzMjlDxFrElNVjE4ZWjo1Ak-JJdmc/edit?tab=t.isfroku1gx3e). This part covers from December 2016 to November 2017. ## The Codeforces Contest Our contest was held on Codeforces, and it broke several records. - The record for the highest number of upvotes on an editorial. - The record f...

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On Div2ABs 2 years ago, [user:antontrygubO_o,2022-04-27] wrote [a blog](https://codeforces.me/blog/entry/75163) about div2ABs where he expressed his opinions that d2ABs should not be about "here is a statement, please implement what is written there". Thanks to him, the quality of d2ABs (and problem quality in general) have certainly improved. However, I still believe that there still quite large differences between how coordinators/problemsetters view d2ABs and how the intended participants view them. From the survey made by [user:kpw29,2022-04-27], we can see that most people agree that most people agree that we should **primarily** consider the target audience when proposing a task. I too think if a task is boring to div 1 contestants, we should not think of that as a reason to immediately disqualify a problem from being a d2A.  I think when people judge the interesting-ness of d2As, they try...

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I Give Up I have been doing cp around a year. But I can't improve. I'm not a engineering/Computer Science student.So all the advice i found online tried to apply.But no results.Even bought course,no results. I'll be honest,I started cp because of job.Someone online gave me advice as i'm not from engineering background.To get a good job I need to be good at cp.To crack the online test and get my resume selected.I need good rating.But now I feel i should give up.I open a question to practice.Can't solve it read editorial and in contest.Can't solve anything. Part of me wants to quit,part of me wants to keep going.But i don't know how?I have read https://codeforces.me/blog/entry/91114 and https://codeforces.me/blog/entry/98806.But i don't improve.Recently someone gave me advice to switch to https://atcoder.jp/home. If there is anyone here who is kind enough to tell me how to practice and what to do how to select questions and what topics to learn(I'm aiming to be Expert)? Just comment your thought...

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Please help me ! Please suggest me something, I am totally depressed Please don't make fun of this, I am serious. I am totally depressed, I even can't solve easy problems, I am practicing since 2 years still newbie ( on original account ) please suggest me, should I quit CP ?. I can't concentrate on my daily task due to this depression what should I do? Please give me some tips/tricks so that I will try to get out of it ! <spoiler summary="Spoiler"> Even I can't Concentrate while personal work, what should I do now. This Depression is ruining my life. </spoiler>

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Dissapointing Community (Recent Top Blog) Not for the faint of heart ================== [user:Kelly,2019-05-06] has recently made an "interesting" blog. I thought that this was a community about cp. But for some reason, people seem to have a peculiar interest in [user:Kelly,2019-05-06]'s blog. The blog has reached the top of CF. I am disappointed in people's taste for literature. Not only that [user:Kelly,2019-05-06] is toxic, it has no place in this community. Top blogs should be about algorithms, tricks, contests and all cp related stuff. Not this kind of crap. Everyone has their own problems. But you don't see those people complaining and whining on the internet. Codeforces is not a place for your personal problems. I know you think your problem is big, but it's not. There are many bigger problems in this world. Like poverty and terrorism. And you. I sincerely hope for everyone to realize the importance of keeping this community sacred. And I do hope for [user:Kelly,2019-05-06] to just quit whining and be like ev...

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Reason I started Competitive Programming Ever since I was a little kid, I always had a huge crush on [user:VPurice,2021-12-23]. He was my idol, my lover, my everything. When I saw him starting competitive programming I suddenly fell in love with it. I started solving problems everyday practicing for more than 8 hours per day. Even though he isn't good at competitive programming at all he still inspires me, him raising from a terrible rank to a bad one amazed me and his motivation and practice routine are all insane. My goal was always to be better than him, even though it was quite easy to achieve, I still haven't quit competitive programming after that, I wanted to become not only better than Victoras, I wanted to destroy him. So I challenged him to a duel of 800 rated problem. As expected, I destroyed him after only 47 minutes of epic duelling. Victor now knows not to mess with me and my family, but we are still the bestest friends. Now my goal in cP is simple, to beat [user:I_love_Driusha,2021-12-23] bestest cper in Ukr...

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How to practice cp top 8 tips oat 1. if ur doing bad in contest stop doing bad so u can do good in contest 2. if ur not sleeping before contest, sleep because then u will have sleep and it will let u have the sleep for contest 3. if u cant pass usaco bronze, start doing usaco platinum so bronze problems will be easy 4. if u cant pass usaco silver learn lazy segment trees. it solves (100^100)% of silver problems 5. if u dont know what an xor operator is, learn from tip 4 6. if u hardstuck on 800 problems give up and become a doctor 7. if u have a rating of 1954 and a high of 2021 ur the greatest cper oat 8. if u dont have tip 7 u should quit and go into business

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Why do I keep losing again, and again, and again, in both cp as well as in life? At this point I feel like some higher power simply toys with me, just to see how much effort I can put in despite knowing that I am going to fail, and laughs at the fact that I still don't quit, and that I still have hope that someday things might work out.

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I couldnt solve B in div 2 in my main account I to demoralised what should I do I would never quit cp but I get very sad when I do bad in contests

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challenge in one year Hello Codeforces community, I challenge myself in one year to become LGM, if I don't achieve that, as a penalty i'm going to quit CP. Proof of grinding full year I will try to upload daily blogs of what I've done. Feel free to dislike blog, that will encourage me to work harder.

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Should I just quit cp? I've realized that I don't have enough iq to do competitive programming. I was doing it for fun but it's not fun anymore cause I can't improve.

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How to kill ten years of your life Hey community. Today I want to share some rather unique experience: how to kill ten years of your life. This whining should appear on some anonymous whiners' site, but I suppose only the CF members can, you know, truly feel all the spectrum. Soon you'll find out that I am very awful English-speaker, but I write it in other language intentionally, because it guarantees no person mentioned in the story would read it. It all began with yet another codejam round, which I totally fucked up. I felt raged and exhausted. To be honest, I feel so after too many contests, and I even had a custom to go for a sole walk after onsites during my ICPC years, just to calm down. I treat contests as a negative-sum game: if you achieved your goal (to proceed to the next round, to win a t-shirt, you name it), you can sleep well today, otherwise you deserve your pain. Nobody of my friends beat that round too, so I opened chat messenger to talk about it. But all I got was some phrases like "don't push yo...

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First virtual participation Done badly and WA on the **eaiest** question ever. Quitting CP soon. [contest:4] #### _Retart I Remain._ #### _As my Handle Suggested._ 

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i am just no good in CP, i guess i should quit well, since months i think coding is not for me, i can barely write a working loop, guess i should work at a inner garment shop

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A Recap of My First Year in CodeForces Hello all on Codeforces! ------------------ It’s been just over a full year since I created my Codeforces account. Since then a lot has happened on my Codeforces journey so far. With everything that’s happened I want to look back at how I got to my current point, share what I learned in the process, recap some of my best moments, and laugh at whatever I was thinking on a few of these contests, because a lot happened. The only issue is that there’s no way I’m going to detail all **60** contests I took part in 2022. Instead I’ve chosen to “award” the 9 most memorable contests, wheter it be because I did exceedingly well or self destructed in almost hilarious fashion. A few notes before I begin: No full solutions for any problems are shown in this post but there are code snippets and discussions that are spoilers for these problems. I apologize in advance. ### First Contest &mdash; [Hello 2022](https://codeforces.me/contest/1621) This was the first contest held in 2022, ...

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Healthyug :The True story Healthyug , You know what You are a LOSER .if you have the guts then we both nerds challenge you again to be LGM on codeforces and you know that we said Top 5 in the world not just india ,so you know you can't reach there that's why you quitting cp .hahaha loser ,if you can't complete challenges don't take it and come back again and try to become LGM.

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